Chitosan membranes in a rat model of full-thickness cutaneous wounds: healing and IL-4 levels

OBJECTIVE

The aim of this study was to examine the effect of chitosan membrane on wound healing.

METHOD

The effect of chitosan membranes was evaluated in an experimental rat model. On day 0, circular full-thickness skin sections were excised from the scalps of rats. The wounds were then measured and the surrounding area tattooed. Rats were sacrificed either immediately after excision, or randomised into control and chitosan groups and followed up on day 3, 7, 14 or 21. Control group wounds were covered with Aquacel (wound dressing). Chitosan group wounds were covered with chitosan membranes and the wound dressing. Wounds and the distances between the tattooed marks were measured on follow-up, the wound sites were harvested and histologically examined, and serum interleukin (IL-4) levels were analysed.

RESULTS

A total of 54 rats were examined and all time points included 6 control and 6 chitosan treated animals, except for day 0 which consisted of control animals only. On day 3, wounds in the chitosan group were significantly (p<0.05) smaller (60±6% versus 78±19% of the original wound area) than in the control group. Chitosan membranes were found to degrade at the wound sites between days 7 and 14. Leukocyte counts were lower in the chitosan group than in the control group on day seven (p<0.05). IL-4 levels were significantly higher on day 7 (p<0.001) and 14 (p<0.001) in the chitosan group.

CONCLUSION

According to our results chitosan membrane may promote early wound healing, reduce inflammation and affect the IL-4 pathway, however, the membrane degrades at the wound site after day 7.

The impact of low-saturated fat, low cholesterol diet on bone properties measured using calcaneal ultrasound in prepubertal children

To analyze the effects of low-saturated fat, low-cholesterol diet on bone in healthy children, calcaneal ultrasound measurements were obtained in 139 subjects (71 girls, 68 boys; mean age 8 years, SD 0.5), who were recruited from the STRIP (Special Turku Coronary Risk Factor Intervention Project) trial. Speed of sound (SOS), broadband ultrasound attenuation (BUA), and quantitative ultrasound index (QUI) values were determined at the dominant heel using a Hologic Sahara scanner. Values were compared with anthropometry and mean, energy-adjusted dietary intakes (absolute intake/1000 kcal) of fat, carbohydrates, protein, cholesterol, calcium, fiber, and the polyunsaturated to saturated fatty acid ratio derived from 4-day food diaries kept once a year between the ages of 2-7 years. The intakes were also analyzed separately at each time point. The BUA, SOS, and QUI values of the intervention children (n = 90) and the control children (n = 49) were similar. No gender differences were found. BUA correlated with age (r = 0.26, P<0.01), height (r = 0.19, P<0.05), and weight (r = 0.22, P<0.05). QUI correlated with mean intake of fat (r = 0.19, P<0.05) and carbohydrate (r = -0.22, P<0.05), SOS with mean intake of cholesterol (r = 0.18, P<0.05), and BUA with mean intake of carbohydrate (r = -0.22, P<0.05). The intakes of fat and cholesterol were lower (P<0.001) and intakes of protein and carbohydrates higher (P<0.01) in the intervention children, but the intakes of calcium were similar. The differences in the dietary intakes persisted throughout the study period. We conclude that dietary counseling aimed at reducing risk of atherosclerosis in later life does not decrease dietary intake of calcium or diminish the calcaneal ultrasound values in the intervention of children in this study. However, since this study is cross-sectional and only one measurement of bone is used, further studies are needed to draw further conclusions about the influence of dietary counseling on bone health.

Dietary plant sterols alter the serum plant sterol concentration but not the cholesterol precursor sterol concentrations in young children (the STRIP Study). Special Turku Coronary Risk Factor Intervention Project

Plant sterol supplementation reduces serum cholesterol concentration but may increase serum plant sterol concentrations, especially in children. We determined whether natural dietary plant sterols derived mainly from vegetable oil or margarine in early childhood affect serum concentrations of plant sterols (campesterol and sitosterol) and cholesterol precursor sterols (Delta-8 cholestenol, desmosterol, and lathosterol), reflecting endogenous cholesterol synthesis. We measured the serum sterol concentrations using gas liquid chromatography in 20 healthy 13-mo-old intervention children in a randomized, prospective study designed to decrease exposure of the children to known environmental atherosclerosis risk factors and in 20 control children. The diet of the intervention children was rich in plant sterols due to replacement of milk fat with vegetable fat, whereas the diet of the control children contained only small amounts of plant sterols. The intervention children consumed twice as much plant sterols as the control children (P < 0.001). Their serum concentrations of campesterol and sitosterol were 75% and 44% higher, respectively, than those in the control children (P < 0.001 for both), but serum cholesterol precursor sterol concentrations did not differ between the two groups. We conclude that doubling dietary plant sterol intake almost doubles serum plant sterol concentrations in 13-mo-old children, but has no effect on endogenous cholesterol synthesis. Relative intestinal absorption of natural plant sterols from the diet in early childhood is similar to that in adults.

Feasibility of, and success in adopting a low-fat diet in coronary patients

The aim of this study was to evaluate the feasibility of dietary counselling and the predictability of success in reducing fat intake to less than 20% of total energy in patients with symptomatic coronary heart disease. Forty-seven patients with coronary heart disease attended a 2-week in-house cardiac rehabilitation course with the main emphasis on individual dietary counselling by a nutritionist. Patients were followed up at 3 and 6 months. The dietary data were collected by means of 3-7 days food diaries. Mean fat intake decreased from 33.6 +/- 6.2% to 24.7 +/- 5.5% of total energy intake at 3 months and to 27.0 +/- 6.9% (p < 0.001) at 6 months. Only 13% of the patients were able to reduce their dietary fat intake as recommended. Thus, reduction of > or = 20% was considered a good response, while reduction of < 20% was classified as poor. Forty-seven percent (n = 22) of the patients were good and 53% (n = 25) poor responders. It was not possible to predict the success rate from the baseline data. After a 2-week intensive counselling period at the rehabilitation centre, half of the coronary patients were able to comply with a low-fat diet at home for 6 months. Long-term compliance requires further investigation.

Prospective, randomized, infancy-onset trial of the effects of a low-saturated-fat, low-cholesterol diet on serum lipids and lipoproteins before school age: The Special Turku Coronary Risk Factor Intervention Project (STRIP)

BACKGROUND

We showed previously that repeated dietary counseling during the first 3 years of life reduces the concentration of serum nonfasting cholesterol. We have now extended the study to children 5 years of age and analyzed fasting blood samples, enabling LDL cholesterol calculations for the first time.

METHODS AND RESULTS

Families of 7-month-old infants (n=1062) were randomized to a control group (n=522) or an intervention group (n=540) that received individualized dietary counseling with the aims of a fat intake of 30% to 35% of daily energy, a saturated/monounsaturated/polyunsaturated fatty acid ratio of 1:1:1, and a cholesterol intake of <200 mg/d. Nutrient intakes were studied biannually, nonfasting serum lipid values were studied annually, and fasting values were studied at 5 years of age. The intervention children always had lower intakes of saturated fat and cholesterol than the control children. The intervention boys had 0.39 mmol/L (P:<0.0001) lower mean serum cholesterol values than the control boys between 13 and 60 months of age, but among girls, the difference was of marginal significance (0.15 mmol/L, P:=0.052). Five-year-old intervention boys had 9% lower mean serum LDL cholesterol concentrations than the control boys (P:=0.0002; 95% CI, -0.39 to -0.12 mmol/L), whereas no difference was observed in girls. In both sexes, serum triglyceride concentrations were similar in the 2 groups.

CONCLUSIONS

The restriction of saturated fat and cholesterol intake by repeated, individualized dietary counseling since infancy resulted in lower serum total and LDL cholesterol concentrations at 5 years of age. However, the effect was significant only in boys.

Neurological development of 5-year-old children receiving a low-saturated fat, low-cholesterol diet since infancy: A randomized controlled trial

CONTEXT

Early childhood introduction of nutritional habits aimed at atherosclerosis prevention is compatible with normal growth, but its effect on neurological development is unknown.

OBJECTIVE

To analyze how parental counseling aimed at keeping children's diets low in saturated fat and cholesterol influences neurodevelopment during the first 5 years of life.

DESIGN

Randomized controlled trial conducted between February 1990 and November 1996.

SETTING

Outpatient clinic of a university department in Turku, Finland.

PARTICIPANTS

A total of 1062 seven-month-old infants and their parents, recruited at well-baby clinics between 1990 and 1992. At age 5 years, 496 children still living in the city of Turku were available to participate in neurodevelopmental testing.

INTERVENTION

Participants were randomly assigned to receive individualized counseling aimed at limiting the child's fat intake to 30% to 35% of daily energy, with a saturated:monounsaturated:polyunsaturated fatty acid ratio of 1:1:1 and a cholesterol intake of less than 200 mg/d (n = 540) or usual health education (control group, n = 522).

MAIN OUTCOME MEASURES

Nutrient intake, serum lipid concentrations, and neurological development at 5 years, among children in the intervention vs control groups.

RESULTS

Absolute and relative intakes of fat, saturated fatty acids, and cholesterol among children in the intervention group were markedly less than the respective values of control children. Mean (SD) percentages of daily energy at age 5 years for the intervention vs control groups were as follows: for total fat, 30.6% (4.5%) vs 33.4% (4.4%) (P<. 001); and for saturated fat, 11.7% (2.3%) vs 14.5% (2.4%) (P<.001). Mean intakes of cholesterol were 164.2 mg (60.1 mg) and 192.5 mg (71. 9 mg) (P<.001) for the intervention and control groups, respectively. Serum cholesterol concentrations were continuously 3% to 5% lower in children in the intervention group than in children in the control group. At age 5 years, mean (SD) serum cholesterol concentration of the intervention group was 4.27 (0.63) mmol/L (165 [24] mg/dL) and of the control group, 4.41 (0.74) mmol/L (170 [29] mg/dL) (P =.04). Neurological development of children in the intervention group was at least as good as that of children in the control group. Relative risks for children in the intervention group to fail tests of speech and language skills, gross motor functioning plus perception, and visual motor skills were 0.95 (90% confidence interval [CI], 0.60-1.49), 0.95 (90% CI, 0.58-1.55), and 0.65 (90% CI, 0.39-1.08), respectively (P =.85,.86, and.16, respectively, vs control children).

CONCLUSION

Our data indicate that repeated child-targeted dietary counseling of parents during the first 5 years of a child's life lessens age-associated increases in children's serum cholesterol and is compatible with normal neurological development. JAMA. 2000;284:993-1000

Sodium intake of 1 to 5-year-old children: the STRIP project. The Special Turku Coronary Risk Factor Intervention Project

The aim of this study is to examine sodium intake and dietary sodium sources of 1-5-y-old children in a prospective, randomized long-term coronary heart disease prevention trial, focused on dietary fat modification. Counselling included no advice about reducing salt in the children's diets. Food consumption of 100 intervention children and 100 control children was recorded for 3 consecutive days at the age of 13 mo and for 4 consecutive days at the ages of 3 and 5 y. Sodium intakes were calculated using the Micro Nutrica program. Children's mean daily sodium (NaCl) consumption (intervention and control children combined) was 1600+/-527 mg (4.0+/-1.3 g), 1900+/-504 mg (4.8+/-1.3 g) and 2200+/-531 mg (5.5+/-1.3 g) at the ages of 13 mo and 3 and 5 y, respectively. The intervention children consumed as much or slightly more sodium than the control children at all ages studied. Half the sodium consumption was derived from added salt in commercially prepared or homemade foods. Milk, meat products, bread and cereals were other important sodium sources. In conclusion, nutrition counselling in the Special Turku Coronary Risk Factor Intervention Project (STRIP) trial, with its main focus on the quality of fat in child nutrition, has had minimal influence on children's sodium intake. To avoid excessive sodium intake in children, dietary counselling should include information about salt use, and food manufacturers should be encouraged to provide more low-sodium products.

Fatty acid composition of serum cholesterol esters as a reflector of low-saturated-fat, low-cholesterol diet in young children: the STRIP project. The Special Turku coronary Risk factor Intervention Project

STRIP (the Special Turku coronary Risk factor Intervention Project) is an ongoing intervention trial which aims at a permanent reduction in the intake of saturated fat and cholesterol starting in childhood. A total of 75 intervention and 63 control children was studied consecutively at the ages of 7 and 13 mo, and 2, 3 and 5 y to evaluate the influence of such intervention on serum cholesterol ester (CE) fatty acid composition, a widely used biomarker of fatty acid intake. Analysis of 4-d food records showed that total intake of fat and of saturated fat increased with age in both groups of children but was constantly lower in intervention than in control children, e.g. at the age of 5 y the mean intakes of total fat and of saturated fatty acids were 31.1 E% and 33.9 E% and 12.1 E% and 14.6 E% in intervention and control children, respectively (p = 0.009 and 0.0001, respectively). Serum CE fatty acid compositions did not differ between the 2 groups at any age; the mean proportion of CE linoleic acid was 52.4% and 52.0% in 5-y-old intervention and control children, respectively. Correlation analysis showed, however, that the percentage of linoleic acid and of polyunsaturated fatty acids in CE reflected well the respective dietary intakes (r = 0.36; p = 0.0001 for both coefficients). In conclusion, CE fatty acid composition did not differ between the intervention and control groups, whereas CE linoleic and total polyunsaturated fatty acids reflected well the differences in their intakes at the individual level.

Low-saturated fat, low-cholesterol diet in 3-year-old children: effect on intake and composition of trans fatty acids and other fatty acids in serum phospholipid fraction-The STRIP study. Special Turku coronary Risk factor Intervention Project for children

OBJECTIVE

We evaluated whether replacing a proportion of saturated fat with vegetable oils in the diet of young children increases trans fatty acid intake.

STUDY DESIGN

Dietary counseling aimed to reach a dietary fat ratio of unsaturated to saturated fat of 2:1 within a total fat intake of 30% to 35% of energy (E%). Four-day food records of 813 3-year-old children were analyzed, and serum phospholipid fatty acid compositions of 25 randomly selected intervention children and 17 control children were analyzed.

RESULTS

trans fatty acid intake of the intervention and control children was small (0.8 E% and 0.6 E%, respectively; P <.001). The relative content of serum phospholipid trans 18:1 was closely similar in intervention and control children (1.0% and 0.9% of all fatty acids, respectively). Trans fatty acid intake and serum trans 18:1 correlated poorly with children's serum cholesterol and HDL cholesterol concentrations and inversely with serum phospholipid arachidonic to linoleic acid ratio (r = -0.373).

CONCLUSIONS

Trans fatty acid intake of children in Finland is minimal. Dietary intervention replacing saturated with unsaturated fatty acids is safe because it does not increase trans fatty acid intake or the relative content of trans fatty acids in the serum phospholipid fraction.

Effect of low-saturated fat, low-cholesterol dietary intervention on fatty acid compositions in serum lipid fractions in 5-year-old children. The STRIP project

OBJECTIVE

To evaluate the effect of dietary low-saturated fat, low-cholesterol intervention on fat intake and fatty acid compositions in serum cholesterol ester (CE), phospholipid (PL) and triglyceride (TG) fractions in five-year-old children.

DESIGN AND SUBJECTS

The STRIP project is a prospective, randomised intervention project in which 1062 seven-month-old infants were recruited from the well-baby clinics. 764 children participated in the 5-year follow-up; 202 of them were randomly selected for this study. Diet was assessed with 4-d dietary records. Serum CE, PL and TG fatty acid compositions were analysed with gas-liquid chromatography.

RESULTS

Saturated fat intake of intervention children (mean (confidence interval)) (girls 11.9 (11.2-12.6) % of energy intake (E%); boys 12.5 (11.9-13.1)) was lower than that of the control children (girls 14.4 (13.7-15.2) E%; boys 15.0 (14.3-15. 8) E%) (P=0.0001 for the difference between intervention and control groups). The intake of unsaturated fat differed only slightly. Dietary ratios of polyunsaturated to saturated fatty acids (PS ratios) of the intervention and control diets were 0.44 and 0.33, respectively (P=0.0001). Furthermore, serum cholesterol concentrations of the intervention and control children differed (4. 28 (4.13-4.43) mmol/L vs 4.49 (4.35-4.63) mmol/L; P=0.04). Relative proportion of saturated fatty acids in serum TG was lower (34.9% vs 36.3%; P=0.04) and that of n-6 polyunsaturated fatty acids higher (13.9% vs 12.4%; P=0.0004) in the intervention than in the control children, whereas serum CE and PL fatty acid compositions of intervention and control groups were closely similar. However, intake of linoleic acid correlated better with serum linoleic acid relative content in the CE fraction (r=0.36; P=0.0001) than in the PL (r=0.27; P=0.0002) or in the TG (r=0.23; P=0.0016) fraction.

CONCLUSIONS

Intervention resulted in decreased intake of saturated fatty acids and lowered serum total and LDL cholesterol concentrations. Of serum lipid fractions, TG fatty acid composition was the most sensitive and parallelled the findings in dietary food records.

Influence of days of the week on reported food, macronutrient and alcohol intake among an adult population in south western Finland

OBJECTIVE

To study the influence of the days of the week on calculated food and nutrient intake.

STUDY DESIGN

Daily variation in food and nutrient intake was studied by using 4-, 5- and 7-d estimated food records, all including Friday, Saturday and Sunday.

SUBJECTS AND SETTING

Two groups of untreated hypertensive patients (60 men and 31 women, aged 31-55 y, and 132 men and 94 women, aged 35-54 y) and a random population sample of 131 men and 139 women, aged 35-64 y, all from the City of Turku and three neighbouring municipalities in south western Finland.

RESULTS

The intakes of meat and meat products, carbohydrate, alcohol and energy varied significantly across the week in all study groups with increased intakes of meat and meat products on Saturday and Sunday, of carbohydrate and alcohol on Friday and Saturday, and of energy on Friday, Saturday and Sunday. Food and nutrient intakes did not vary consistently with weekdays (Monday to Thursday) with the exception of alcohol intake being lowest on Monday. Macronutrient, alcohol and energy intake data calculated from the 5-d (Monday, Tuesday, Friday, Saturday and Sunday) and from 5 to 7 d converted food records were nearly equal to and correlated highly (r=0.96-0.98) with the data calculated from the 'true' 7 d records.

CONCLUSION

The daily variation in food and nutrient intakes should be taken into consideration when food diaries are recorded. 5-d food records including two weekdays (from Monday to Thursday) and Friday, Saturday and Sunday is recommended.

SPONSORSHIP

Social Insurance Institution of Finland.

Milk hypersensitivity in young adults

OBJECTIVE

To estimate the prevalence of milk hypersensitivity in Finnish adults.

DESIGN

Cross-sectional study.

SUBJECTS

Two hundred men and 206 women aged 27 y randomly recruited from the population register in southwestern Finland.

INTERVENTIONS

The subjects were interviewed about their dairy product consumption, abdominal discomfort after dairy product intake and lactose intolerance. From serum samples, serum reactivity to milk protein and milk-specific IgG1, IgG2, IgG3 and IgA were measured.

RESULTS

About 20% of the subjects reported abdominal discomfort after dairy product intake, whereas only 6.4% had been diagnosed to have lactose intolerance. The amount of milk consumed correlated well with the serum assay results in subjects reporting abdominal discomfort but not in subjects who were free from these symptoms. Among subjects with no record of dairy product restriction or lactose intolerance, those experiencing abdominal discomfort after dairy product intake had significantly higher serum reactivity to milk protein than those without such discomfort. The concentrations of serum milk-specific antibodies did not differ between these two groups. The prevalence of milk hypersensitivity in this population was estimated to be 3-6%.

CONCLUSIONS

Milk hypersensitivity may be as common in adults as in infants. The measurement of serum reactivity to milk protein may prove useful in screening milk hypersensitivity in subjects who have not restricted their dairy product consumption.

Nutrient intakes and cholesterol values of the parents in a prospective randomized child-targeted coronary heart disease risk factor intervention trial--the STRIP project

OBJECTIVE

To analyze food consumption, nutrient intakes and serum cholesterol concentrations of the parents in a child-targeted CHD intervention trial, during which the age of children increased from 7 months to 5 y.

DESIGN AND SUBJECTS

The children were randomized to an intervention group (n = 540) or a control group (n = 522) at six months of age. The intervention families were counseled at 3-6 month intervals to reduce their child's intake of saturated fat and cholesterol. Dietary issues were discussed with the control families only briefly. The parents' food consumption was analyzed by 24 h dietary recall at the child's age of 7 and 13 months and at 2, 3, 4, and 5 y. Nutrient intakes were calculated using the Micro-Nutrica program.

RESULTS

The mothers and fathers of the intervention children used less butter, more margarine and more skim milk than those of the control children (P < 0.001 for all measurements). After the onset of counseling, the intervention mothers consumed continuously less fat (1.4 E% less at the child's age of 5 y), less saturated fat (1.5 E% less at the child's age of 5 y) and more polyunsaturated fat (0.5 E% more at the child's age of 5 y) than the control mothers (P = 0.008, P < 0.001 and P < 0.001 for trend, respectively). After the child's age of 13 months the intervention fathers also had a continuously lower fat intake (2.4 E% less at the child's age of 5 y) and consumed less saturated fat (1.5 E% less at the child's age of 5 y) than the control fathers (P < 0.001 for trend for both measurements). The serum cholesterol concentration of the intervention mothers was consistently lower than that of the control mothers during the intervention (at child's age of 5 y 4.86 and 5.09 mmol/L, respectively; P for trend = 0.03), while the values of the intervention and control fathers showed no differences.

CONCLUSIONS

Continuous dietary intervention begun in infancy and focused on modification of the child's diet according to the current principles of preventive cardiology, was accompanied by a moderate decrease in the intake of total and saturated fat in the parents, but serum cholesterol concentration diminished consistently only in the mothers of the intervention children.

Serum cholesterol ester fatty acids in 7- and 13-month-old children in a prospective randomized trial of a low-saturated fat, low-cholesterol diet: the STRIP baby project. Special Turku coronary Risk factor Intervention Project for children

To evaluate changes that occur in serum cholesterol ester fatty acid composition during the transition from typical infant feeding to a more adult type of nutrition, this study compared the effects on serum cholesterol ester fatty acids of breast milk or formula at the age of 7 mo with effects caused by 6-mo dietary intervention in 137 children. The intervention [Special Turku coronary Risk factor Intervention Project for children (STRIP baby project)] aimed at a reduction of saturated fat intake to 10% of energy after the age of 1 y without purposefully influencing total fat intake. Nutrient intakes were calculated from 3-d food records. At the age of 7 mo, i.e. before dietary education began, milk type markedly influenced dietary and serum cholesterol ester fatty acid composition (mean serum cholesterol ester 16:0 in breastfed vs formula-fed infants, 13.7% vs 12.0%, respectively, p < 0.001; serum cholesterol ester 18:2n-6 50.6% vs 57.6%, p < 0.001). At the age of 13 mo the calculated fat intake of the intervention and control children differed markedly but serum cholesterol ester fatty acid compositions in all children resembled closely those measured in 7-mo-old breastfed infants, e.g. at the age of 13 mo the relative proportions of 18:2n-6 were 49.9% and 51.1% in previously formula-fed intervention and control children, respectively, and 50.3% and 50.1% in previously breastfed intervention and control children, respectively. In conclusion, serum cholesterol ester fatty acid composition reflected differences in dietary fat quality (breast milk or formula) at the age of 7 mo, whereas dietary intervention as applied in the STRIP baby project had only a minimal effect.

Influence of dietary fat on the nutrient intake and growth of children from 1 to 5 y of age: the Special Turku Coronary Risk Factor Intervention Project

BACKGROUND

Excessive decreases in fat intake in young children have been linked with low intakes of energy and nutrients and possible growth failure.

OBJECTIVE

We evaluated nutrient intakes and growth of healthy children with different fat intakes during the first 5 y of life.

DESIGN

In the Special Turku Coronary Risk Factor Intervention Project (STRIP), 7-mo-old children were randomly assigned to an intervention aimed at reduced consumption of saturated fat and cholesterol (n = 540) or to a control group (n = 522). This analysis comprises data for children for whom > or = 6 of 8 possible 3-4-d food records were available (n = 730; 353 females). Children were divided according to fat intake pattern (percentage of energy) between the ages of 13 mo and 5 y into groups with continuously high fat intake (5% of children), increasing fat intake (5%), continuously low fat intake (5%), decreasing fat intake (5%), and average fat intake (80%). Children's energy and nutrient intakes and growth were then compared by analysis of variance.

RESULTS

Fat intake at 13 mo of age was particularly low (21% of energy) in the increasing fat intake group and in the continuously low fat intake group (22% of energy at 13 mo; 26% of energy at 5 y). Growth of children in all 5 fat intake groups, however, was not significantly different throughout the study period. Intakes of vitamins and minerals, except of vitamin D, met recommended dietary allowances in all fat intake groups.

CONCLUSION

Nutrient intakes and growth were not significantly different in children whose fat intake patterns differed between 13 mo and 5 y of age.

[Salt intake in young children]

Among adult Finns salt intake is about twice as high as the recommended levels and almost five-fold greater than the physiological requirement. Information as to salt intake in children has hitherto been sparse. Daily sodium intake among 1-5-year-olds was investigated in this study, and the foodstuffs from which it was derived were identified. In all age groups, sodium intake was at least two-fold greater than the Nordic recommendations, and among five-year-olds it exceeded the recommended intake for adults. Approximately half of the sodium intake was found to have derived from salt used in cooking. Levels of sodium derived by children from dairy, meat and grain products were also relatively high. Sodium intake in children after infancy merits greater attention than previously accorded it, as permanent eating habits and taste preferences are already formed at this age, and reasonable limits for salt intake should therefore be established during childhood.

Regulation of growth of 7- to 36-month-old children by energy and fat intake in the prospective, randomized STRIP baby trial

OBJECTIVE

To study the fat and energy intakes of children between 7 and 36 months of age with different growth patterns.

METHODS

In the Special Turku coronary Risk factor Intervention Project for Babies, children were randomized to intervention (n = 540) and control groups (n = 522) at age 7 months. The intervention was aimed at replacing part of the saturated fat intake with monounsaturated and polyunsaturated fat to reduce children's exposure to high serum cholesterol values. The control children consumed a free diet. Children followed for >2 years (n = 848) were included in the analysis. Five groups of children representing different extreme growth patterns during the first 3 years of life were formed, and their energy and fat intakes were analyzed. Relative weight was defined as deviation of weight in percentages from the mean weight of healthy children of same height and sex, and relative height as deviation of height in SD units from the mean height of healthy children of same age and sex.

RESULTS

Relative fat intakes (as percent of energy intake) were similar in children showing highly different height gain patterns. The thin (mean relative weight </= 5%) children consumed more fat (mean, 30% energy [ E%] [SD 7] at 13 months and 33 [4] E% at 24 months) than children with normal growth (27 [5] E% at 13 months and 31 [5] E% at 24 months). The energy intake of the tall (mean relative height >/= 95%) and the obese (mean relative weight >/= 95%) were highest, but weight-based energy intake of the tall (at 2 years, 82 [13] kcal/kg) and the obese (79 [17] kcal/kg) were lower than that of children with normal growth (89 [16] kcal/kg). The thin children consumed relatively more energy than the children with normal growth (at 2 years, 94 [13] kcal/kg and 89 [16] kcal/kg, respectively). Parental height and body mass index and the child's absolute and relative energy intakes predicted the best children's growth patterns. Children with consistently low fat intake grew equally to the children with higher fat intake.

CONCLUSIONS

Moderate supervised restriction of fat intake to values 25 to 30 E% is compatible with normal growth.

Salivary cholesterol of healthy adults in relation to serum cholesterol concentration and oral health

Salivary lipids are mostly glandular in origin, but some are believed to diffuse directly from serum. This diffusion and the role of salivary lipids in oral health have scarcely been studied. Therefore, the serum and saliva cholesterol concentrations and oral health were analyzed in a group of healthy adults (n = 139; 64 men and 75 women; 34.2 +/- 5.2 yrs). Paraffin-stimulated whole saliva was collected, centrifuged (10,000 x g; 30 min, 4 degrees C), and lyophilized, and the cholesterol and other neutral lipids were extracted, separated by thin-layer chromatography, and quantified. The mean +/- SD (range) of saliva cholesterol concentration was 1.20 +/- 0.75 (0.02-5.46) mumol/L, and the saliva cholesterol level of men (1.36 +/- 0.85 mumol/L) was significantly higher than that of women (1.06 +/- 0.64 mumol/L; p < 0.05). Weak positive correlations between saliva and serum cholesterol concentrations and saliva cholesterol and serum non-high-density lipoprotein cholesterol concentrations were found (r = 0.22, p < 0.05; r = 0.28, p < 0.005, respectively). The saliva cholesterol assay detected subjects with high (> or = 6.5 mmol/L) serum cholesterol values, with sensitivity and specificity values of 100% and 29%, respectively. A positive correlation between the body mass index and the level of saliva cholesterol concentration was also found (r = 0.31 p < 0.01). Oral health, microbial counts, or saliva flow rate revealed no differences in subjects with low and high salivary cholesterol level. We conclude that, in healthy adults, saliva cholesterol concentration reflects serum concentration to some extent and can be used to select individuals with high serum cholesterol levels.

Intake and indicators of iron and zinc status in children consuming diets low in saturated fat and cholesterol: the STRIP baby study. Special Turku Coronary Risk Factor Intervention Project for Babies

A low-fat diet may predispose children to low meat consumption, low iron intake, and iron deficiency. In the randomized prospective Special Turku Coronary Risk Factor Intervention Project for Babies (STRIP baby study), families of 540 children were counseled to reduce exposure of children > 7 mo of age to known environmental risk factors for coronary heart disease. The control group consisted of 522 children whose families received no specific counseling concerning dietary fat. Iron and zinc intakes of 79 children aged 3-4 y (40 in the intervention group and 39 in the control group) were assessed with 4-d food records. The children in the intervention group consumed less saturated fat than those in the control group and had continuously higher ratios of dietary polyunsaturated to saturated fatty acids. Mean (+/- SD) daily iron intakes in the intervention and control groups were 8.8 +/- 4.2 mg and 8.6 +/- 2.8 mg, respectively. Laboratory findings in the intervention and control groups, respectively, were as follows: hemoglobin, 123 +/- 8 and 122 +/- 7 g/L; mean cell volume, 81.8 +/- 2.9 and 81.7 +/- 3.2 fL; mean corpuscular hemoglobin, 28.1 +/- 1.3 and 27.8 +/- 1.4 pg; ferritin, 21.8 +/- 11.6 and 19.2 +/- 12.4 microg/L; transferrin, 2.90 +/- 0.30 and 2.85 +/- 0.29 g/L; and transferrin receptor, 2.34 +/- 0.46 and 2.29 +/- 0.39 mg/L. There were no significant differences between the groups. Daily zinc intakes were 7.5 +/- 1.2 mg in the intervention group and 7.4 +/- 1.3 mg in the control group; respective serum zinc concentrations were 11.2 +/- 1.9 and 10.5 +/- 1.6 micromol/L (NS). In conclusion, long-term supervised use of a diet low in saturated fat and cholesterol did not influence intake or serum indicators of iron and zinc in children.

Dietary flavonoids and the risk of lung cancer and other malignant neoplasms

Flavonoids are effective antioxidants and, in theory, may provide protection against cancer, although direct human evidence of this is scarce. The relation between the intake of antioxidant flavonoids and subsequent risk of cancer was studied among 9,959 Finnish men and women aged 15-99 years and initially cancer free. Food consumption was estimated by the dietary history method, covering the total habitual diet during the previous year. During a follow-up in 1967-1991, 997 cancer cases and 151 lung cancer cases were diagnosed. An inverse association was observed between the intake of flavonoids and incidence of all sites of cancer combined. The sex- and age-adjusted relative risk of all sites of cancer combined between the highest and lowest quartiles of flavonoid intake was 0.80 (95% confidence interval 0.67-0.96). This association was mainly a result of lung cancer, which presented a corresponding relative risk of 0.54 (95% confidence interval 0.34-0.87). The association between flavonoid intake and lung cancer incidence was not due to the intake of antioxidant vitamins or other potential confounding factors, as adjustment for factors such as smoking and intakes of energy, vitamin E, vitamin C, and beta-carotene did not materially alter the results. The association was strongest in persons under 50 years of age and in nonsmokers with relative risks of 0.33 (95% confidence interval 0.15-0.77) and 0.13 (95% confidence interval 0.03-0.58), respectively. Of the major dietary flavonoid sources, the consumption of apples showed an inverse association with lung cancer incidence, with a relative risk of 0.42 (95% confidence interval 0.23-0.76) after adjustment for the intake of other fruits and vegetables. The results are in line with the hypothesis that flavonoid intake in some circumstances may be involved in the cancer process, resulting in lowered risks.

Growth until 3 years of age in a prospective, randomized trial of a diet with reduced saturated fat and cholesterol

OBJECTIVE

Modification of fat intake in childhood may decrease children's future risk for atherosclerosis. Excessive changes in fat intake have been linked with possible growth failure. This study evaluates the effects of a low-saturated fat diet on growth during the first 3 years of life.

DESIGN

Half of 1062 healthy infants were randomized at 7 months of age to the intervention group (n = 540) to receive at 1- to 6-month intervals individualized dietary counseling aimed at reducing their exposure to atherosclerosis risk factors. Five hundred twenty-two children served as control children. Growth and serum lipids were measured regularly, and nutrient intakes were analyzed using 3- to 4-day food records at 5- to 12-month intervals.

RESULTS

The intervention children consistently consumed slightly less energy than did the control children. The mean fat intake of children in both groups was lower than expected, especially during the first 2 years of life (29.0 [SD, 4.7] percentage of energy intake [E%] and 28.8 [4.1] E% in the intervention and control children, respectively, at 8 months, formula-fed children only). At 13, 24, and 36 months, fat intake in the intervention and control children accounted for 26.2 (6.0) and 27.9 (4.9) E%, 29.9 (5.0) and 32.8 (4.8) E%, and 30.8 (4.9) and 33.2 (4.6) E%, respectively. From 13 to 36 months, the baseline adjusted mean serum cholesterol concentration was lower in the intervention children than the control children (95% confidence interval for the difference between means, -0.27 to -0.12 mmol/L). The true mean of the height of the boys in the intervention group during the trial was at most 0.34 cm more or 0.57 cm less (95% confidence interval), and the weight was at most 0.19 kg more or 0.22 kg less than that of the control boys. The respective values for girls were at most 0.77 cm more or 0.16 cm less and at most 0.42 kg more or 0.04 kg less. The numbers of slim children were similar in both groups.

CONCLUSIONS

Fat intake by young children is markedly lower than assumed. A supervised low-saturated fat, low-cholesterol diet has no influence on growth during the first 3 years of life.

Diet and breast cancer risk in a cohort of Finnish women

The associations between dietary antioxidant vitamins, dietary fiber, and selected foods and risk of breast cancer were studied in 4697 initially cancer-free women, aged 15 years or older. At baseline (1967-1972) the women were interviewed for total habitual diet over the preceding year. During a 25-year follow-up period 88 breast cancer cases were diagnosed. There was a significant inverse gradient between milk consumption and occurrence of breast cancer, whereas higher consumption of fried meat was associated with increased risk of breast cancer. No significant relationships were found between the intakes of vitamin E, vitamin C, beta-carotene, lycopene, lutein or dietary fiber and the occurrence of breast cancer.

Nutrient intakes by young children in a prospective randomized trial of a low-saturated fat, low-cholesterol diet. The STRIP Baby Project. Special Turku Coronary Risk Factor Intervention Project for Babies

OBJECTIVE

To evaluate the impact of individualized and repeatedly given dietary counseling on fat intake and nutrient intake of children aged 8 months to 4 years.

DESIGN

Prospective randomized clinical trial.

PARTICIPANTS

Children (N = 1062) from 1054 families were randomized to an intervention (n = 540) or a control (n = 522) group when each child participant was 6 months old.

INTERVENTIONS

The children in the intervention group were counseled to reduce their intake of saturated fat and cholesterol but to ensure their adequate energy intake. Dietary issues were discussed with the families of the children in the control group only briefly according to the current practice of well-baby clinics.

MAIN OUTCOME MEASURES

Food consumption was evaluated by using 3- and 4-day food records that were kept at 5- to 12-month intervals, and nutrient intakes were analyzed with a Micro Nutrica computer program (Social Insurance Institution, Turku, Finland).

RESULTS

The intake of fat (29% of the energy intake) and cholesterol (70 mg) showed no differences between the groups of children at 8 months of age. The fat intake in the children in the intervention group was then continuously 2% of the energy intake below that of the children in the control group (P < .001). After the age of 13 months, the cholesterol intake of the children in the control group exceeded that of the children in the intervention group by 20 mg (P < .001). The children in the intervention group consumed 3% (of the energy intake) less saturated (P < .001) and 1% (of the energy intake) more polyunsaturated fats (P < .001) than did the children in the control group at age 13 months and older. The carbohydrate intake was slightly higher in the children in the intervention group than in the children in the control group. Intakes of vitamins, minerals, and trace elements showed no differences between the 2 groups.

CONCLUSIONS

The intakes of fat by the children in the intervention and control groups were markedly below values that were recommended for the first 2 years of life. Despite the low intake of fat, the intake of other nutrients fulfilled current recommendations, except for vitamin D and iron. Individualized dietary counseling that led to clear changes in the type of fat intake had a minimal effect on vitamin or mineral intakes.

Oral health of 3-year-old children and their parents after 29 months of child-focused antiatherosclerotic dietary intervention in a prospective randomized trial

A long-term prospective, randomized dietary intervention to prevent exposure of children to the known atherosclerosis risk factors (the STRIP baby project) was started when the age of the children was 7 months. The aim of this substudy was to analyze the oral effects of the dietary intervention in the children and their parents when the children had reached the age of 3 years. Every fifth family of the main study was invited to this substudy (n = 179). Those studied (n = 148) represented well the intervention and the control groups and both genders in terms of intake of saturated fatty acids, the dietary polyunsaturated fatty acid to saturated fatty acid (PUFA/SAFA) ration and serum cholesterol and HDL cholesterol concentrations. Though no difference was found in sucrose consumption between the intervention and the control groups, the intervention children received relatively (in E%) more energy from carbohydrates than the control children (p < 0.005), used absolutely (in g) and relatively (in E%) less fat (p < 0.05) and had a higher PUFA/SAFA ratio in their diet (p < 0.001). Of the 3-year-old children 93% were caries free, and dental decay was a prevalent in the intervention as in the control children. Control children brushed their teeth unassisted more often than the intervention children (p < 0.05). The intervention fathers also received more energy (in E%) from carbohydrates (p < 0.01), the intervention mothers used less fat (p < 0.05) and had a higher PUFA/SAFA ratio in the diet (p < 0.05) than the control fathers and mothers, respectively. Dental and periodontal health of the intervention and control parents (n = 250, 84% attending, mean +/- SD age: 34.2 +/- 54.5 years also showed no differences even though the control parents had more commonly last visited a dentist over 3 years before this examination (p < 0.05). We conclude that a 29-month period of a low-saturated-fat, low-cholesterol but high-carbohydrate diet as advocated in the STRIP baby trial does not seem to have harmful effects on the oral health of the children or their parents. Minor untoward differences had occurred in the dental health behavior of the control children and their parents.

Prospective randomized trial of low-saturated-fat, low-cholesterol diet during the first 3 years of life. The STRIP baby project

BACKGROUND

The long-term consequences of modified fat intake in early childhood are poorly known. The randomized prospective STRIP baby project evaluates the effects of repeated dietary counseling on nutrient intakes and serum lipid values in children 7 months to 3 years old.

METHODS AND RESULTS

One thousand sixty-two infants were randomized to intervention and control groups at 7 months of age. The families of the 540 intervention children were counseled to reduce the child's intake of saturated fat and cholesterol but to ensure adequate energy intake. Five hundred twenty-two control children consumed an unrestricted diet. Food records were kept, and serum lipids were measured at 5- to 12-month intervals. Intakes of saturated fat, fat as proportion of energy (E%), and cholesterol were lower in the intervention children than in control children at 13, 24, and 36 months of age. Fat intake by the intervention children decreased from 29 +/- 5 E% at 8 months of age to 26 +/- 6 E% at 13 months and then increased to 30 +/- 5 E% at 24 months and to 31 +/- 5 E% at 36 months. The control children consumed 29 +/- 4 E%, 28 +/- 5 E%, 33 +/- 5 E%, and 33 +/- 5 E% of fat at 8, 13, 24, and 36 months, respectively. The ratio of dietary poly-unsaturated to saturated fats of the intervention children was consistently higher than that of the control children (P < .0001). Baseline adjusted mean serum cholesterol concentration was lower in the intervention children than control children between 13 and 36 months (P < .0001; 95% confidence interval of the difference between the group means, -0.27 to -0.12 mmol/L). The effect was significant only in boys (95% confidence interval, -0.39 to -0.20 mmol/L in boys; -0.21 to 0.01 mmol/L in girls).

CONCLUSIONS

Repeated individualized dietary counseling markedly reduces the increase in serum cholesterol concentration that occurs in control children during the first years of life.

Changes in diet in Finland from 1972 to 1992: impact on coronary heart disease risk

BACKGROUND

Coronary heart disease mortality has declined in Finland by 55% among men and 68% among women between 1972 and 1992. About three-quarters of this decline has been explained by changes in the main coronary risk factors, the decrease in serum cholesterol being the most important one. The aim of this study was to analyze to what extent dietary changes could explain the change in serum cholesterol.

METHODS

Cardiovascular risk factor surveys have been carried out in Finland from 1972 to 1992 at 5-year intervals. Dietary surveys were carried out in connection with these surveys in 1982 and 1992. An earlier, representative dietary survey carried out in 1969-1972 was used as the baseline measure for diet.

RESULTS

The total fat content of the Finnish diet changed from 38% of energy to 34%, saturated fat from 21 to 16%, and polyunsaturated fat from 3 to 5% and the intake of cholesterol decreased by 16%. Based on Keys equation these changes could have decreased serum cholesterol level by 0.6 mmol/liter (23 mg/dl) in both genders. A shift from boiled to filtered coffee could have further decreased serum cholesterol by 0.3 mmol/liter (11 mg/dl). Thus, these changes together could explain the total change in serum cholesterol, which has been on average 1.0 mmol/liter (38 mg/dl). Several other changes in the diet have also been favorable. Fruit and vegetable consumption has increased two- to three-fold during this time period. Supplementation of fertilizers with selenium since 1985 has tripled the intake of selenium.

CONCLUSIONS

Dietary changes seem to explain the decrease in serum cholesterol. Together with a decline in smoking among males as well as better blood pressure control they have contributed to the dramatic decline in coronary heart disease mortality in Finland.

Effects of prospective, randomized cholesterol-lowering dietary intervention and apolipoprotein E phenotype on serum lipoprotein(a) concentrations of infants aged 7-24 mo

A high serum lipoprotein(a) [Lp(a)] concentration is associated with increased risk of coronary artery disease. Few external factors are able to markedly modify serum Lp(a) concentrations. The aim of this study was to evaluate how serum Lp(a) concentrations of infants between 7 and 24 mo of age change in a cholesterol-lowering dietary intervention, and to assess the influence of apolipoprotein (apo) E phenotypes on serum Lp(a) concentrations. The intervention children (n=394) had serum cholesterol, non-high-density-lipoprotein cholesterol, and cholesterol corrected for Lp(a)-cholesterol values (P for all <0.001) lower than those of the control children (n=390), but median serum Lp(a) concentrations at the age of 24 mo were not different from those of control children. Serum Lp(a) values differed according to the apo E phenotype as the median Lp(a) values increased from E2/2 to E3/2, E4/2, E3/3, E4/3, and to E4/4 (P for the difference=0.023, Mann-Whitney U test). Our results suggest that apo E phenotype influences serum Lp(a) concentrations noticeably, but the effect of the cholesterol-lowering dietary intervention was not significant in subjects aged 24 mo.

Intake of dairy products and the risk of breast cancer

The relationship between intake of dairy products and risk of breast cancer was studied in 4697 initially cancer-free women, aged 15 years or over. During a 25 year follow-up period after the collection of food consumption data, 88 breast cancers were diagnosed. Intakes of foods were calculated from dietary history interviews covering the habitual diet of examinees over the preceding year. There was a significant inverse gradient between milk intake and incidence of breast cancer, the age-adjusted relative risk of breast cancer being 0.42 (95% confidence interval=0.24-0.74) between the highest and lowest tertiles of milk consumption. The associations with respect to other dairy products were not significant. Adjustment for potential confounding factors, i.e. smoking, body mass index, number of childbirths, occupation and geographic area, resulted in only a minor change in the milk intake-breast cancer relation. Nor did adjustment for intake of other foodstuffs and nutrients, e.g. energy, carbohydrates, protein, fat, vitamins and trace elements, alter the results. No significant interactions between milk intake and demographic or dietary variables or time of cancer diagnosis were observed. Our data suggest that there is a protective effect, dietary or habitual, associated with consumption of milk that overwhelms the associations between different other factors and risk of breast cancer.

Body iron stores, dietary iron intake and coronary heart disease mortality

OBJECTIVES

To assess whether increased body iron stores and dietary iron intake are associated with an increased risk of coronary heart disease mortality.

DESIGN

A prospective population study with a mean mortality follow-up time of 14 years.

SETTING

Participants attending a health screening examination carried out in several localities in Finland.

SUBJECTS

All 6086 men and 6102 women aged from 45 to 64 years at the baseline examination without known heart disease, who had had serum iron and total iron binding capacity (TIBC) assessed. In a random fifth of these people, dietary iron intake was assessed by a dietary history.

INTERVENTIONS

The study was observational without any interventions.

MAIN OUTCOME MEASURES

Mortality from coronary heart disease.

RESULTS

Altogether, 739 of the men and 245 of the women died from coronary heart disease. No relationship between TIBC and coronary mortality was observed in the men; in the women, an inverse although not significant association was found. Transferrin saturation was inversely but not significantly associated with coronary mortality in men; in women, the relationship was U-formed with a higher mortality at both the lower and higher ends of the distribution. Adjustment for other risk factors did not alter the results. No association was found with dietary iron intake and coronary mortality.

CONCLUSIONS

The results do not corroborate earlier findings that excess body iron stores and increased iron intake are associated with an elevated risk of coronary heart disease.

Prospective randomised trial in 1062 infants of diet low in saturated fat and cholesterol

Interventions to avoid atherosclerosis might be more successful if launched early in life when eating and life-style patterns are formed, but dietary interventions have been limited by fears of diet-induced growth failure. We investigated the effects of a diet low in saturated fat and cholesterol on serum lipid concentrations and growth in 1062 healthy 7-month-old infants in a randomised study. Every 1-3 months, families in the intervention group received dietary advice aimed at adequate energy supply, with low fat intake (30-35% energy, polyunsaturated/monounsaturated/saturated fatty acid ratio 1/1/1, and cholesterol intake < 200 mg daily). Infants in control families consumed an unrestricted diet. 3-day food records were collected at ages 8 and 13 months. Growth was carefully monitored. Between 7 and 13 months serum cholesterol and non-high-density-lipoprotein cholesterol concentrations did not change significantly in the intervention group (mean change -0.03 [SD 0.72] mmol/L and 0.01 [0.67] mmol/L) but increased substantially in the control group (0.24 [0.64] mmol/L and 0.23 [0.60] mmol/L; p for difference in mean changes between groups < 0.001). Daily intakes of energy and saturated fat were lower in the intervention than in the control group at 13 months (4065 [796] vs 4370 [748] kJ, p = 0.033, and 9.3 [3.5] vs 14.5 [4.8] g, p < 0.001, respectively), and intake of polyunsaturated fat was higher (5.8 [2.2] vs 4.4 [1.4] g, p < 0.001). Growth did not differ between the groups and was as expected for children at this age. Serum cholesterol concentrations fell significantly in parents of intervention-group infants. The increases in serum cholesterol and non-high-density-lipoprotein cholesterol concentration that occur in infants between the ages of 7 and 13 months can be avoided by individualised diets, with no effect on the children's growth.

Antioxidant vitamins in the diet: relationships with other personal characteristics in Finland

STUDY OBJECTIVE

The study aimed to reveal associations between dietary antioxidant vitamins and other personal characteristics.

DESIGN

Population based, cross sectional survey.

SETTING

Twenty seven rural, industrial, and semiurban communities in six different regions of Finland.

PARTICIPANTS

Subjects included 5304 men and 4750 women aged 15 years or older, who were interviewed about their dietary habits at the baseline study of the Finnish Mobile Clinic Health Examination Survey, 1967-72.

MAIN RESULTS

Intakes of carotenoids and vitamins A, E, and C were estimated from dietary history interviews covering the subjects' food consumption in the preceding year. In older age groups intakes of all the vitamins studied were low. Occupation had a profound effect on dietary antioxidant vitamins: intakes were highest in white collar workers and lowest in farmers; those classified as service workers, industrial workers, or housewives came in between. Current smoking was inversely associated with dietary carotenoids and vitamin C, especially in men. The vitamin intakes of ex-smokers were equal to or even slightly higher than those of never smokers. Married men had higher intakes of carotenoids and vitamin C than men living alone. Body mass index was not an important determinant of the intake of antioxidant vitamins.

CONCLUSIONS

The associations of dietary antioxidant vitamins with sociodemographic characteristics and smoking were strong enough to exert a confounding or modifying effect in studies on diet and diseases.

Exercise, smoking, and calcium intake during adolescence and early adulthood as determinants of peak bone mass. Cardiovascular Risk in Young Finns Study Group

OBJECTIVE

To evaluate the contribution to peak bone mass of exercise, smoking, and calcium intake in adolescents and young adults.

DESIGN

Prospective cohort study with end point measurement (bone mineral density) after 11 years' follow up for lifestyle.

SETTING

Five university hospital clinics.

SUBJECTS

264 (153 females, 111 males) subjects aged 9 to 18 years at the beginning of the follow up and 20 to 29 years at the time of measurement of bone mineral density.

MAIN OUTCOME MEASURE

Bone mineral density of lumbar spine and femoral neck by dual energy x ray absorptiometry; measures of physical activity and smoking and estimates of calcium intake repeated three times during follow up.

RESULTS

In the groups with the lowest and highest levels of exercise the femoral bone mineral densities (adjusted for age and weight) were 0.918 and 0.988 g/cm2 for women (P = 0.015, analysis of covariance) and 0.943 and 1.042 g/cm2 for men (P = 0.005), respectively; at the lumbar spine the respective values were 1.045 and 1.131 (P = 0.005) for men. In men the femoral bone mineral densities (adjusted for age, weight, and exercise) were 1.022 and 0.923 g/cm2 for the groups with the lowest and highest values of smoking index (P = 0.054, analysis of covariance). In women the adjusted femoral bone mineral density increased by 4.7% together with increasing calcium intake (P = 0.089, analysis of covariance). In multiple regression analysis on bone mineral density of the femoral neck, weight, exercise, age, and smoking were independent predictors for men; with weight, exercise, and age for women. These predictors together explained 38% of the variance in bone mineral density in women and 46% in men. At the lumbar spine, weight, smoking, and exercise were predictors for men; and only weight for women.

CONCLUSIONS

Regular exercise and not smoking is important in achieving maximal peak bone mass in adolescents and young adults.

Antioxidant vitamin intake and coronary mortality in a longitudinal population study

Oxidation of lipoproteins is hypothesized to promote atherosclerosis and, thus, a high intake of antioxidant nutrients may protect against coronary heart disease. The relation between the intakes of dietary carotene, vitamin C, and vitamin E and the subsequent coronary mortality was studied in a cohort of 5,133 Finnish men and women aged 30-69 years and initially free from heart disease. Food consumption was estimated by the dietary history method covering the total habitual diet during the previous year. Altogether, 244 new fatal coronary heart disease cases occurred during a mean follow-up of 14 years beginning in 1966-1972. An inverse association was observed between dietary vitamin E intake and coronary mortality in both men and women with relative risks of 0.68 (p for trend = 0.01) and 0.35 (p for trend < 0.01), respectively, between the highest and lowest tertiles of the intake. Similar associations were observed for the dietary intake of vitamin C and carotenoids among women and for the intake of important food sources of these micronutrients, i.e., of vegetables and fruits, among both men and women. The associations were not attributable to confounding by major nondietary risk factors of coronary heart disease, i.e., age, smoking, serum cholesterol, hypertension, or relative weight. The results support the hypothesis that antioxidant vitamins protect against coronary heart disease, but it cannot be excluded that foods rich in these micronutrients also contain other constituents that provide the protection.

Low serum 25-hydroxyvitamin D concentrations and secondary hyperparathyroidism in middle-aged white strict vegetarians

The vitamin D status of vegetarians was studied in the winter. The groups studied were strict vegetarians (G1), lactovegetarians (G2), lactoovovegetarians eating some fish (G3), and vegetarians who were taking vitamin D supplements or who had been exposed to abundant sunlight during the last 6 mo (G4). A group of healthy women served as control subjects (C). The serum 25-hydroxyvitamin D [25(OH)D] concentration was significantly lower, the serum intact parathyroid hormone (S-iPTH) concentration significantly higher, and the dietary vitamin D intake significantly lower in G1 than in C. S-iPTH correlated negatively with serum 25(OH)D and dietary calcium intake. In conclusion, white strict vegetarians are at risk of vitamin D deficiency, at least in the winter, primarily because of a low dietary vitamin D intake, despite a normal sunlight exposure in summer. Low serum 25(OH)D concentrations are accompanied by high S-iPTH concentrations, which also are affected by a low calcium intake. The effect of these changes on bone health remains to be evaluated.

Short-term and long-term reproducibility of dietary history interview data

This study gives results for comparisons between dietary history interviews repeated at short-term (4-8 months) and long-term (4-7 years) intervals in conjunction with the Finnish Mobile Clinic Health Examination Survey. Interviews surveying the whole range of consumable foods over the preceding year were completed in 1967-1976. Short-term study was accomplished among 93 adults, and long-term study among 1844 adults. Comparisons were made for intakes of 32 food groups and 32 nutrient indices. In the short term, the intraclass correlation coefficients for nutrient indices ranged from 0.16 to 0.80, with 90% of values higher than 0.5. The corresponding figures for repeated measurements at long-term interval were generally poorer, being in the range 0.12-0.60, with 45% of values > 0.5. When studied in population subgroups, long-term agreement in dietary data was not found to be affected by sex, age, body mass index or smoking status, but it may be reduced among heavier drinkers (> or = 20 g alcohol per day). The intraclass correlation coefficients for separate nutrients tended to be higher than those for different food groups. In conclusion, we suggest that the reproducibility of the dietary history method used was acceptable, and that the dietary patterns of examinees were sufficiently stable to be compatible with the needs of epidemiological follow-up studies.

Long-term antiepileptic efficacy of vigabatrin in drug-refractory epilepsy in mentally retarded patients. A 5-year follow-up study

The long-term clinical, neurophysiologic, and psychological effects of add-on vigabatrin treatment were evaluated in a group of 36 mentally handicapped patients with drug-refractory epilepsy. After an initial 3-month follow-up period, 15 (42%) of 36 patients had at least a 50% decrease in seizure frequency compared with baseline. After a 2-year follow-up period, nine (25%) of 36 patients retained the initially observed antiepileptic effects of vigabatrin, and after 5 years, eight (22%) of 36 patients did so. Five (33%) of the 15 patients who initially exhibited a favorable antiepileptic response to vigabatrin lost that response during a 5-year follow-up. Partial-onset seizures represented the seizure type best controlled by vigabatrin. Side effects were mostly mild, and plasma levels of other antiepileptic medication remained unchanged. No impairment of psychological performance was observed during vigabatrin treatment compared with baseline. Also, no clear change was observed in the background or epileptiform activity in the electroencephalogram during the study. Our findings suggest that vigabatrin as an add-on therapeutic effectively controls seizures in a subpopulation of patients with severe epilepsy. In addition, the antiepileptic response, if achieved, is long lasting in about half of the patients.

Dietary determinants of serum beta-carotene and serum retinol

The relationship of major dietary carotenoids, preformed and total vitamin A, and different foods to serum beta-carotene and serum retinol levels was studied among 224 male and 117 female adults taken from the Finnish Mobile Clinic Health Examination Survey. Serum nutrients were analysed after 10-15 years of storage at -20 degrees C. Dietary data were collected by a quantitative dietary history interview method. Intakes of nutrients were calculated based on analysed data on Finnish foods. The positive gradient between beta-carotene intake and serum level, being highly significant in women and non-significant in men, was concentrated in non-smokers. Other major dietary carotenoids tended to be positively correlated with serum beta-carotene in parallel with dietary beta-carotene. Carrot intake was the most specific single food predictor for serum beta-carotene. Serum retinol levels were not significantly associated with dietary variables and were not affected by current smoking. In women, serum beta-carotene values were higher, but serum retinol levels lower, compared with men. The results support earlier findings that smoking modifies the association between dietary beta-carotene and serum beta-carotene, and suggest that despite the long storage of serum samples beta-carotene determinations had some value as a biological marker for beta-carotene in the diet.

High stored iron levels are associated with excess risk of myocardial infarction in eastern Finnish men

BACKGROUND

Iron can induce lipid peroxidation in vitro and in vivo in humans and has promoted ischemic myocardial injury in experimental animals. We tested the hypothesis that high serum ferritin concentration and high dietary iron intake are associated with an excess risk of acute myocardial infarction.

METHODS AND RESULTS

Randomly selected men (n = 1,931), aged 42, 48, 54, or 60 years, who had no symptomatic coronary heart disease at entry, were examined in the Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) in Eastern Finland between 1984 and 1989. Fifty-one of these men experienced an acute myocardial infarction during an average follow-up of 3 years. On the basis of a Cox proportional hazards model adjusting for age, examination year, cigarette pack-years, ischemic ECG in exercise test, maximal oxygen uptake, systolic blood pressure, blood glucose, serum copper, blood leukocyte count, and serum high density lipoprotein cholesterol, apolipoprotein B, and triglyceride concentrations, men with serum ferritin greater than or equal to 200 micrograms/l had a 2.2-fold (95% CI, 1.2-4.0; p less than 0.01) risk factor-adjusted risk of acute myocardial infarction compared with men with a lower serum ferritin. An elevated serum ferritin was a strong risk factor for acute myocardial infarction in all multivariate models. This association was stronger in men with serum low density lipoprotein cholesterol concentration of 5.0 mmol/l (193 mg/dl) or more than in others. Also, dietary iron intake had a significant association with the disease risk in a Cox model with the same covariates.

CONCLUSIONS

Our data suggest that a high stored iron level, as assessed by elevated serum ferritin concentration, is a risk factor for coronary heart disease.

Leanness and lung-cancer risk

Body mass index (weight/height2) was studied for its prediction of lung cancer in Finnish men examined by the Social Insurance Institution's Mobile Clinic and followed up by the Finnish Cancer Registry. Among 25,994 participants aged 20 to 75 years and free from cancer at the start of the study, 504 lung-cancer cases were diagnosed during a maximum follow-up of 19 years. There was a significant inverse gradient between body mass index and the incidence of lung cancer. This association was not due to confounding by age, smoking, social class, self-perceived general health, history of stress symptoms, chronic cough or chest X-ray findings, although these factors correlated with body mass index and were also significantly predictive of lung cancer. After adjustment for these factors, the relative risks of lung cancer were 1.0, 1.4, 1.5 and 1.8 (p for trend less than 0.001) from the highest to the lowest quartiles of body mass index. The association was noted among current smokers, but it was most obvious among men who had never smoked, the relative risk of lung cancer between the lowest and highest quartiles of body mass index being 7.6 (95% confidence interval = 2.0 to 29.4). The inverse gradient persisted throughout the entire follow-up period, and was most distinct after the first 10 years of follow-up, the relative risks for the quartiles of body mass index being 1.0, 1.9, 2.3 and 2.6 (p less than 0.001). The present study shows that the thinner the man, the more liable he is to develop lung cancer. Leanness or some factor or cluster of factors closely correlated to it, may play an aetiological role in lung cancer.

Dietary antioxidants and the risk of lung cancer

The relation between the intake of retinoids, carotenoids, vitamin E, vitamin C, and selenium and the subsequent risk of lung cancer was studied among 4,538 initially cancer-free Finnish men aged 20-69 years. During a follow-up of 20 years beginning in 1966-1972, 117 lung cancer cases were diagnosed. Inverse gradients were observed between the intake of carotenoids, vitamin E, and vitamin C and the incidence of lung cancer among nonsmokers, for whom the age-adjusted relative risks of lung cancer in the lowest tertile of intake compared with that in the highest tertile were 2.5 (p value for trend = 0.04), 3.1 (p = 0.12), and 3.1 (p less than 0.01) for the three intakes, respectively. Adjustment for various potential confounding factors did not materially alter the results, and the associations did not seem to be due to preclinical cancer. In the total cohort, there was an inverse association between intake of margarine and fruits and risk of lung cancer. The relative risk of lung cancer for the lowest compared with the highest tertile of margarine intake was 4.0 (p less than 0.001), and that for fruits was 1.8 (p = 0.01). These associations persisted after adjustment for the micronutrient intakes and were stronger among nonsmokers. The results suggest that carotenoids, vitamin E, and vitamin C may be protective against lung cancer among nonsmokers. Food sources rich in these micronutrients may also have other constituents with independent protective effects against lung cancer.

Dietary cholesterol, fatty acids, and the risk of lung cancer among men

The relation between dietary cholesterol and fatty acids and the incidence of lung cancer was studied among 4,538 Finnish men aged 20-69 years and initially free of cancer. During 20 years of follow-up, 117 lung cancer cases were diagnosed. Cholesterol intake was not associated with lung cancer risk, the age-, smoking-, and energy-adjusted relative risk between the lowest and highest tertiles being 1.0 [95% confidence interval (CI) = 0.6-1.9]. The intake of saturated fatty acids was nonsignificantly related with lung cancer incidence, the relative risk for the lowest compared with the highest tertile being 1.6 (CI = 0.8-3.2). The association was stronger among smokers than among nonsmokers, the relative risks being 2.1 (CI = 1.0-4.3) and 1.3 (CI = 0.4-4.1), respectively. The relative risk among smokers, however, decreased to 1.5 after adjustment for the amount they smoked. In the total cohort, there was a significantly elevated risk of lung cancer among men with a high intake of butter, one of the main sources of saturated fatty acids, the relative risk being 1.9 (CI = 1.1-3.2). The present data do not confirm previous results suggesting that dietary cholesterol predicts the occurrence of lung cancer among men. The association between intake of saturated fatty acids and lung cancer observed in the present study may be partly due to heavy smoking among high consumers of saturated fat.

Dietary fat and risk of breast cancer

The relationship between dietary fat and subsequent risk of breast cancer was studied in 3988 initially cancer-free Finnish women aged 20-69 y. During a follow-up period of 20 y, 54 breast-cancer cases were diagnosed. Risk of breast cancer was significantly inversely related to energy intake and nonsignificantly inversely related to absolute fat intake. A positive association between energy-adjusted total fat intake and occurrence of breast cancer was also observed. The relative risk in the highest tertile as compared with the lowest tertile was 1.7 (95% confidence limits 0.6-4.8). The corresponding relative risks were 1.4 (0.5-3.7) for saturated fatty acids, 2.7 (1.0-7.4) for monounsaturated fatty acids, 1.2 (0.6-2.8) for polyunsaturated fatty acids, and 2.2 (1.0-5.0) for cholesterol intake. Adjustment for different potential confounding factors did not alter the results. The present data suggest that breast cancer is associated inversely with energy intake and weakly positively with energy-adjusted fat intake.

Blood pressure, dietary fats, and antioxidants

We investigated the association of dietary fatty acids and antioxidants with blood pressure in 722 eastern Finnish men aged 54 y, examined in the Kuopio Ischaemic Heart Disease Risk Factor Study in 1984-86. Men with self-reported hypertension or cerebrovascular disease or under antihypertensive medication were excluded. Allowing for the major anthropometric, dietary, medical, and psychological determinants of blood pressure in multivariate regression analyses, both plasma ascorbic acid (p = 0.0008) and serum selenium (p = 0.0017) concentrations had a moderate, independent inverse association, estimated dietary intake of saturated fatty acids had a positive association (p = 0.013), and estimated dietary intake of linolenic acid had an inverse (p = 0.048) association with the mean resting blood pressure. The marked elevation of blood pressure at the lowest levels of plasma ascorbic acid and serum Se concentrations supports the hypothesis that antioxidants play a role in the etiology of hypertension.

Determinants of serum alpha-tocopherol in Finnish adults

The relationship between serum alpha-tocopherol level and many of its possible determinants was studied in 1,373 cancer-free Finnish men and women age 40-79 years. Dietary data were available from a subsample of 301 persons. The mean alpha-tocopherol level in the serum samples stored at -20 degrees C was 8.6 mg/liter among men and 10.5 mg/liter among women. Intake of margarine, vegetable oils, and green vegetables predicted the serum level of alpha-tocopherol. Altogether six food groups accounted for about 10% of the variation. The levels also varied with age, geographical area, type of population, occupation, socioeconomic status, and marital status. They were positively correlated with serum cholesterol and serum vitamin A in both sexes, and with body mass index and serum selenium in men. Altogether these variables accounted for over 40% of the variation in alpha-tocopherol levels. The level of serum alpha-tocopherol, which is associated with the dietary intake of vitamin E, is dependent upon living conditions.

Nonstarch polysaccharide consumption in four Scandinavian populations

Nonstarch polysaccharide (NSP) intake was measured in representative samples of 30 men aged 50-59 in 2 urban and 2 rural Scandinavian populations that exhibited a 3-4 fold difference in incidence of large bowel cancer. Intake was measured by chemical analysis of complete duplicate portions of all food eaten over one day by each individual. NSP intakes showed a rural-urban gradient, with 18.4 +/- 7.8 g/day in rural Finland and 18.0 +/- 6.4 g/day in rural Denmark versus 14.5 +/- 5.4 g/day in urban Finland and 13.2 +/- 4.8 g/day in urban Denmark. NSP intakes were also calculated (using food tables) from weighed food records kept over 4 days, one of which was the day on which the duplicate collection was made. Intakes were 2-2.5 g/day higher with this method than with direct chemical analysis, mainly because published tables of values have become outdated and inaccurate as a result of improved methods for measuring NSP in food. Individual variation from day to day in NSP intake was considerable. Average NSP intake and intake of some of its component sugars were inversely related to colon cancer incidence in this geographical comparison. To show a relationship at the individual level between diet and cancer risk in a prospective study would require detailed and accurate methods for the assessment of NSP consumption.