Plasma cytokine concentrations of children with autism spectrum disorder and neurotypical siblings

Several studies of autism spectrum disorder (ASD) have shown cytokine dysregulation in children with ASD, leading to a consideration of the immune theory of the ASD etiopathogenesis and a debate about cytokines as potential biomarkers of ASD. However, the results of these studies are still inconsistent. Overall, studies comparing the cytokine levels of children with ASD and neurotypical siblings achieved relatively different results than studies with control groups of non-siblings. The studies suggest that the immune profile of siblings of individuals with ASD serving as control is more similar to children with ASD than the profile of non-siblings. However, there are still only a few studies with control groups including neurotypical siblings of children with ASD. The aim of our study was to determine whether the concentration of plasma cytokine levels may differentiate children with ASD from their neurotypical siblings. The sample consisted of 40 children with ASD (mean age 7.11 years, SD 2.9) and 21 neurotypical siblings (mean age 7.38, SD 3.3). Levels of 20 cytokines were included into the statistical analysis. A multiple logistic regression model using multiple corrections showed that an increase in log-transformed plasma G-CSF (granulocyte colony stimulating factor) concentration is associated with an increased risk of the child being diagnosed as an ASD case (OR = 4.35, 95% CI 1.77, 10.73). Although the significantly increased concentration of G-CSF suggests a slightly different activity of the immune system of children with ASD, the overall cytokine profile of their siblings appeared to be very similar.

Fecal calprotectin levels correlate with main domains of the autism diagnostic interview-revised (ADI-R) in a sample of individuals with autism spectrum disorders from Slovakia

Autism spectrum disorders (ASD) are neurodevelopmental disorders characterized by impaired social interaction and communication, as well as repetitive behavior and restricted interests. There is convincing evidence that the intestinal inflammation is involved in etiology of ASD. Increased levels of inflammatory markers were shown to be associated with more aberrant behaviors and communication of subjects with ASD. Calprotectin in the feces is produced by activated neutrophils and epithelial cells of the gut mucosa, and its levels reflect local inflammation of the gastrointestinal tract. Concentration of fecal calprotectin was determined by ELISA method in 87 individuals with ASD and 51 controls, of that 29 siblings of children with ASD and 22 non-related controls. In non-relatives significantly lower values of fecal calprotectin were observed than in both subjects with ASD and their siblings. In the group with ASD significant correlations of fecal calprotectin with all domains of the ADI-R diagnostic tool were found: qualitative abnormalities in reciprocal social interaction and communication, restrictive and repetitive patterns of behavior. Results suggest that low grade intestinal inflammation may be one of factors implicated in the pathophysiology of ASD.

Increased plasma levels of the high mobility group box 1 protein (HMGB1) are associated with a higher score of gastrointestinal dysfunction in individuals with autism

Autism is a disorder of neural development characterized by impairments in communication, social interaction, restricted interests and repetitive behavior. The etiology of autism is poorly understood, the evidence indicates that inflammation may play a key role. In autism a high prevalence of gastrointestinal disturbances is reported, that are linked to a low-grade chronic inflammation of the intestinal mucosa. High mobility group box 1 protein (HMGB1) is an intranuclear protein that can be passively released from necrotic cells or actively secreted under inflammatory conditions as alarmin or late proinflammatory cytokine. The objective of this study was to measure plasma levels of HMGB1 in individuals with autism and to analyze their association with gastrointestinal symptoms. The study involved 31 subjects with low-functioning autistic disorder aged 2-22 years and 16 healthy controls. Plasma HMGB1 levels were significantly higher in individuals with autism than in controls (13.8+/-11.7 ng/ml vs. 7.90+/-4.0 ng/ml, p<0.02). In subjects with plasma HMGB1 levels higher than 11 ng/ml severe forms of GI disorders were more prevalent (83.3 %) than in subjects with lower levels (38.9 %, p<0.04). Results of the study support the involvement of the systemic low-grade inflammation in the pathomechanisms of autism and its possible association with GI symptoms.

[Intestinal microbiota and the brain: multilevel interactions in health and disease]

Commensal bacteria of the digestive tract are separated from the brain by multiple barriers. Despite that bacteria residing in the intestine and the neurons of the brain interact by neural and humoral pathways. Mental processes, such as the stress response, may affect the composition and function of intestinal bacteria via the brain-gut axis. On the other hand, intestinal bacteria can influence the processes in the brain through the gut-brain axis. Disruption of these interactions may be involved in various alterations both in the function of the gastrointestinal tract and the brain function.

Dietary patterns and lifestyle in a sample of a Slovak Romany community

The aim of this paper is to evaluate dietary habits and behavioural factors related to atherosclerosis in Slovak Romany, the large minority, characterized by high cardiovascular morbidity. The study involved 150 Romany volunteers (68 males, mean age 42.1 +/- 13.9 y and 82 females, mean age 40.9 +/- 13.7 y). Dietary data were obtained by a validated food-requency questionnaire and a single 24-hour dietary recall. The nutrient intake and health behaviour of the Romany population is not consistent with current guidelines for atherosclerosis prevention. The mean intake of fat is higher than the recommended dietary allowance (RDA), especially in males (155.3 % of RDA). In females the intake of alpha-linolenic acid is low, in males the cholesterol content of the food exceeds the acceptable value. The mean intake of protein is higher than the recommendation (males 153% of RDA, females 122.2%), with a high proportion of animal protein. In both sexes the mean intake of vitamins is below the RDA. In comparison to the general population the diet of the Romany males contains significantly more animal protein (p < 0.05), less plant protein (p < 0.05) and folate (p < 0.01). In the diet of the Romany females a significantly lower intake of plant protein (p < 0.05) and vitamin E (p < 0.05) was observed, as well as a lower intake of linoleic acid and iron in both sexes. The cumulation of ten selected cardiovascular risk factors showed that particularly the Romany males could be considered as having more atherogenic profile.

Association of metabolic syndrome risk factors with selected markers of oxidative status and microinflammation in healthy omnivores and vegetarians

Conditions predisposing to metabolic syndrome (MetS) are associated with increased oxidative stress and inflammation. We studied, in vegetarians (n = 90) and omnivores (n = 46), the impact of the dietary regimen on the occurrence of MetS risk factors (RFs: BMI, blood pressure, glucose metabolism and lipid profile) in relation to oxidative status (advanced glycation end products (AGEs), advanced oxidation protein products (AOPPs), malondialdehyde, ferric reducing ability of plasma, vitamins A, E, C, beta-carotene and superoxide dismutase activity) and microinflammation (C-reactive protein, leukocytes and neopterin). The proportion of subjects without/positive for one or two MetS RFs was comparable between the groups. From the components of MetS only immunoreactive insulin levels differed significantly (95% CI: omnivores: 5.0-7.1 microU/mL, vegetarians: 4.5-5.4, p = 0.03). Omnivores had lower AOPP (omnivores: 0.29-0.36 micromol/g albumin, vegetarians: 0.36-0.52, p = 0.01) and beta-carotene levels than vegetarians, they consumed more calories, proteins, fat and saturated fatty acids, and less fibres, beta-carotene and vitamin C. Multiple regression analysis revealed vitamin E and AOPP levels as the most important independent determinants of MetS RFs. The vegetarian diet seems to exert beneficial effects on MetS RFs associated microinflammation. Whether the vegetarian diet may counteract the deleterious effects of elevated AOPPs and AGEs, remains to be elucidated.

No evidence of insulin resistance in normal weight vegetarians

BACKGROUND

Diets rich in carbohydrates with a low glycemic index and with high fiber content are associated with flat post-prandial rises of blood glucose, minimal post-prandial insulin secretion and maintenance of insulin sensitivity. Protective food commodities in the prevention of cardiovascular disease, insulin resistance syndrome or diabetes are crucial components of the vegetarian diet.

AIM OF THE STUDY

Insulin resistance values were assessed in relation to different nutrition. Metabolic abnormality is a predictor of age-related diseases and can be more pronounced in obese subjects. Insulin resistance values in normal weight subjects of two different nutritional habits were correlated with age.

METHODS

Fasting concentrations of glucose and insulin as well as calculated values of insulin resistance IR (HOMA) were assessed in two nutritional groups of apparently healthy adult subjects (age range 19 - 64 years) with normal weight (body mass index 18.6 - 25.0 kg/m(2)): a vegetarian group (95 long-term lacto-ovo-vegetarians; duration of vegetarianism 10.2 +/- 0.5 years) and a non-vegetarian control group (107 subjects of general population on traditional western diet). Intake of energy and main nutrients (fats, saccharides, proteins) was similar in both groups.

RESULTS

Glucose and insulin concentrations and IR (HOMA) values were significantly lower in vegetarians (glucose 4.47 +/- 0.05 vs. 4.71 +/- 0.07 mmol/l; insulin 4.96 +/- 0.23 vs. 7.32 +/- 0.41 mU/l; IR (HOMA) 0.99 +/- 0.05 vs. 1.59 +/- 0.10). IR (HOMA) dependence on age was only significant in subjects on a western diet. A significant increase of IR was found already in the age range 31-40 years, compared to vegetarians and it continued in later age decades. Age independent and low insulin resistance values in vegetarians are a consequence of an effective diet prevention by long-term frequent consumption of protective food. Vegetarians had a significantly higher consumption of whole grain products, pulses, products from oat and barley.

CONCLUSION

The results of age independent and low values of insulin resistance document a beneficial effect of long-term vegetarian nutrition in prevention of metabolic syndrome, diabetes and cardiovascular disease.

[Nutritional status in adults on an alternative or traditional diet]

BACKGROUND

Plant food lacks vitamin B12, vitamin D and higher n-3 polyunsaturated fatty acids. Essential aminoacids methionine and lysine can be found in significantly lower amounts. On the contrary, the culinary and technologically non-processed plant food and whole-grain products contain essential nutrients in a highly condensed form. The aim of the study was to compare nutritional status of adults on alternative or on traditional diet and sequels of the diet to body metabolism.

METHODS AND RESULTS

The group on alternative diet consisted of 89 lacto-ovo-vegetarians (age 38.7 +/- 0.6 years, average duration of vegetarianism 7.8 years). Control group on traditional diet (omnivores, n = 84) was formed as an average sample. Nutritional regime was determined using dietetic questionnaire on the food intake regularity. Vegetarians consume optimal amount of fat (along with recommendations of OVD) with predominance of vegetal lipids. They have low intake of cholesterol (62.8 mg), recommended ratio of saturated fatty acids (SFA), monounsaturated (MUFA), and polyunsaturated (PUFA) 6.5:10.6:8.9 energetic percent. Their ratio of linolic:alpha-linolenic acid (10.4:1) also corresponds with recommendations. In traditional diet, the content of lipids and energy usually exceeds the norm of OVD (by 33% or 19% respectively), cholesterol intake is much higher (512.2 mg, 200 mg is recommended as a maximum). Higher is the amount taken of SFA (11.2 energetic %, recommended 7%), and not sufficient is the intake of alpha-linolenic acid (68% of OVD). People on alternative diet have low plasma levels of risk lipid parameters and significantly higher levels of antisclerotic substances. As a result of significantly higher intake of fruits and vegetables, plant oil, sprouts, seeds, and whole-grain food the plasma levels of antioxidative vitamins are in vegetarians higher then threshold. It reduces the risk of the free-radical disease. On the contrary, vegetarians have deficits in methionine intake, and 15% of them have hypoproteinemia is (0% in omnivores). Low plasma levels of iron and calcium, occurrence of hyposideremia (16% versus 2%) and hypocalcemia (21% versus 8%) corresponds with intake of vegetal absorption inhibitors (fytolic acid, oxalic acid, roughage). Frequently a mild form of hyperhomocysteinemia is found (28% versus 5%), resulting vitamin B12 deficit.

CONCLUSIONS

Vegetarian diet is optimal for prevention of free-radical diseases, especially those of the cardiovascular system. It may bring a risk from the point of view of low iron and calcium absorption, low intake of methionine and occurrence of mild forms of hyperhomocysteinemia. In traditional diet, total lipid content should be lowered, amount of vegetable oil with alpha-linolenic acid should be elevated as well as fruit and vegetable consummation. Whole grain food and oily seeds should be included into the daily food.

Correlation of carnitine levels to methionine and lysine intake

Plasma carnitine levels were measured in two alternative nutrition groups--strict vegetarians (vegans) and lactoovovegetarians (vegetarians consuming limited amounts of animal products such as milk products and eggs). The results were compared to an average sample of probands on mixed nutrition (omnivores). Carnitine levels were correlated with the intake of essential amino acids, methionine and lysine (as substrates of its endogenous synthesis), since the intake of carnitine in food is negligible in the alternative nutrition groups (the highest carnitine content is in meat, lower is in milk products, while fruit, cereals and vegetables contain low or no carnitine at all). An average carnitine level in vegans was significantly reduced with hypocarnitinemia present in 52.9% of probands. Similarly, the intake of methionine and lysine was significantly lower in this group due to the exclusive consumption of plant proteins with reduced content of these amino acids. Carnitine level in lactoovovegetarians was also significantly reduced, but the incidence of values below 30 micromol/l was lower than in vegans representing 17.8% vs. 3.3% in omnivores. Intake of methionine and lysine was also significantly reduced in this group, but still higher compared to vegans (73% of protein intake covered by plant proteins). Significant positive correlation of carnitine levels with methionine and lysine intake in alternative nutrition groups indicates that a significant portion of carnitine requirement is covered by endogenous synthesis. Approximately two thirds of carnitine requirement in omnivores comes from exogenous sources. The results demonstrate the risks of alternative nutrition with respect to the intake of essential amino acids, methionine and lysine, and with respect to the intake and biosynthesis of carnitine.

Homocysteine levels in vegetarians versus omnivores

Vitamin B(12), folate, and vitamin B(6) are the main determinants of homocysteinemia. The vegan diet provides no vitamin B(12), but also less strict forms of alternative nutrition may suffer from a deficit of this vitamin. The plasma homocysteine level was measured in alternative nutrition groups of adults (lacto- and lactoovovegetarians, n = 62; vegans, n = 32) and compared with the levels in a group consuming traditional diet (n = 59), omnivores). In the group of vegetarians the average homocysteine level is 13.18 vs. 10.19 micromol/l in omnivores; the frequency of hyperhomocysteinemia is 29 vs. 5% in omnivores. In the group of vegans the average homocysteine value is 15.79 micromol/l (53% of the individual values exceeded 15 micromol/l). Omnivores consume the recommended amount of methionine; however, in individuals consuming an alternative diet, the intake of methionine is deficient (assessed by food frequency questionnaire; lower content of methionine in plant proteins). Under conditions of lower methionine availability the remethylation pathway prevails; therefore, vitamin B(12) and folate were evaluated in relation to the homocysteine level. The serum vitamin B(12) levels are significantly lower in the alternative nutrition groups (214.8 pmol/l in vegetarians, 140.1 pmol/l in vegans vs. 344.7 pmol/l in omnivores); a deficit (<179.0 pmol/l) was found in 26% of the vegetarians and in 78% of the vegans vs. 0% in omnivores. The serum folate levels were within the range of reference values in all groups; however, they were significantly lower in omnivores. The results show that the mild hyperhomocysteinemia in alternative nutrition is a consequence of vitamin B(12) deficiency.

Traditional and alternative nutrition--levels of homocysteine and lipid parameters in adults

Values of homocysteine and lipid parameters were measured in groups of adults consuming alternative nutrition (vegetarians/lactoovo/, vegans) and compared with a group consuming traditional diet (omnivores, general population). Frequency of hyperhomocysteinemia was 53% in the vegans group, 28% in vegetarians vs. 5% in omnivores. In conditions of lower methionine intake (reduced content in plant proteins), the remethylation pathway of homocysteine metabolism prevails and it is vitamin B12 and folate-dependent. The intake of vitamin B12 is equal to zero in vegans; vegetarians consume 124% of the RDA vs. 383% in omnivores. Serum vitamin levels are significantly lower in subjects consuming alternative nutrition with deficiency observed in 24% of vegetarians, 78% of vegans vs. 0% in omnivores. Serum folate levels are within the reference range in all groups. Mild hyperhomocysteinemia in the groups consuming alternative diet is a consequence of vitamin B12 deficiency. Vegetarians and vegans meet the RDA for energy and fat, and have a favourable proportion of saturated, mono- and polyunsaturated fatty acids on total energy intake; the ratio of linoleic/alpha-linolenic acid in their diet corresponds with the recommendations. They have low cholesterol consumption and higher vitamin E and C intake. Optimal fat intake of correct composition is reflected in lower values of atherosclerosis risk factors (cholesterol, LDL-cholesterol, atherogenic index, saturated fatty acids, triacylglycerols), and significantly higher levels of protective substances (linoleic acid, alpha-linolenic acid, HDL-cholesterol, vitamin E, vitamin E/cholesterol, vitamin C). Low lipid risk factors but higher findings of mild hyperhomocysteinemia in vegetarians mean a diminished protective effect of alternative nutrition in cardiovascular disease prevention.

Serum selenium levels in healthy Slovak children and adolescents

Blood serum selenium levels were measured in 891 healthy children and adolescents (aged 11-18 yr, 450 girls and 441 boys) residing in both rural and urban areas from eight regions of Slovakia. Subjects were divided into four age groups (11-12 y, 13-14 y, 15-16 y, and 17-18 y). Serum selenium concentration was determined by the electrothermal atomic absorption spectrometric method. The mean (+/-SD) serum selenium concentrations were 0.750+/-0.255 micromol/L in girls and 0.773+/-0.235 micromol/L in boys. A large proportion of the individuals (25.7% in girls, 18.1% in boys) exhibited serum selenium levels under 0.57 micromol/L (45 microg/L). An increasing trend of the serum selenium values with age has been observed in both boys (p < 0.01) and girls (p < 0.05). Boys had higher serum selenium levels in the all age groups but the differences were not statistically significant.

[The plasma profile of fatty acids in vegetarians]

The plasma profile of fatty acids has been observed in 27 vegetarian adults, their age ranging from 20 to 63 years (13 men, 14 women) with the average period of vegetarian dietary pattern being 8.8 years. A third of the men and a half of the women were lacto-vegetarians, the rest of them were lacto-ovo-vegetarians. The contents of saturated and monounsaturated fatty acids insignificantly decreased in vegetarians when compared with non-vegetarians (n = 26, 12 men, 14 women, average group of non-smokers with mixed nutrition). The results of parameters regarded as positive factors in vegetarian diet and effective in prevention of atherosclerosis are as follows: significantly higher values of linoliec acid C 18:2, a significantly higher ratio of linoliec/leic acids C 18:2/C18:1 and insignificantly higher value of linolenic acid C 18:3, together with an unchanged, or moderately decreased contents of poly-unsaturated fatty acids C 20:4 (arachidonic acid) and C 22:6 (n3; docosahexaenoic acid). Further prooxidative-antioxidative parameters were selected in regard to the theoretical anticipation of risk brought about by increased lipoperoxidation in vegetarians (poly-unsaturated fatty acids-substrate of the process) which is significant in the etiology of cardio-vascular and oncologic diseases. Their favourable values (significantly lower plasma contents of conjugated dienes of fatty acids, significantly higher plasma value of vitamin C, Beta-carotene, vitamin E/cholesterol-protection of LDL, vitamin E/triacylglycerols-protection of fatty acids, 3.5 times more significant positive linear correlation of vitamin E/triacylglycerol versus plasma contents of C 18:2) eliminate the risk of increased lipoperoxidation in vegetarians. (Tab. 3, Fig. 1, Ref. 29.)

[Serum levels of vitamins A, C and E in the population of Slovakia]

BACKGROUND

Significant forms of vitamin deficiencies are rare in Slovak Republic, however mild hypovitaminoses are still relatively frequent and they have negative consequences on the functional status. Vitamins A, C and E represent an important part of the antioxidant defense system acting against free-radical damage. Imbalance between oxidative stress and antioxidant capacity which leads to free radical damage is considered to be an aetiological factor of ischaemic heart disease and cancer.

OBJECTIVES

The study was focused on assessment of serum levels of vitamins A, C and E in the Slovak population older than 35 y and frequency of decreased levels. Relationship between high prevalence of chronic non-communicable diseases and high frequency of suboptimal levels of antioxidant vitamins is discussed.

METHODS

Serum levels of vitamin A and E were assessed by the HPLC method, the levels of vitamin C by the colorimetric method.

RESULTS

Mean levels of vitamin A were 1.85 mumol/l in both sexes (95% c.i. 1.75-1.89 in males, 1.77-1.92 in females). Mean level of vitamin C was 31.36 mumol/l in males (95% c.i. 30.06-32.72), the value observed in females was significantly higher (43.05 mumol/l, 95% c.i. 41.75-44.40). Mean level of vitamin E observed in males (29.2 mumol/l, 95% c.i. 27.62-30.87) was only slightly, not significantly higher than in females (28.11 mumol/l, 95% c.i. 26.45-29.87). Decreased levels of vitamin E were observed only in a small proportion of the sample, however almost one third of males had decreased level of vitamin C and more than 20% had low level of vitamin A. We observed high prevalence of serum levels of vitamins A, C and E suboptimal from the aspect of risk of coronary heart disease and cancer (vitamin A: males 78%, females 75.5%, vitamin E: 41.9 and 49.6%, respectively, vitamin C: 61.8% and 41.1%).

CONCLUSION

Results indicate that sizeable proportion of population has decreased serum levels of vitamins, males especially of vitamin C and females of vitamin A. According to serum levels of vitamin A, C and E high percentage of population can be ranked into the group with increased risk of CHD and cancer. (Tab. 6, Ref. 29.)

[Serum selenium levels in children and adolescents in selected regions in Slovakia]

BACKGROUND

There is a limited number of data concerning blood serum selenium levels in children and adolescents in the Slovak Republic.

OBJECTIVES

The aim of this study was to access blood serum selenium levels in 102 healthy children (11-14 y) and 122 adolescents (15-18 y) from two regions: The district of Cadca and Modra--Pezinok area.

METHODS

Serum selenium was determined by electrothermal atomic absorption spectrophotometric method using Pd as a matrix modifier.

RESULTS

The mean (+/- SD) serum selenium concentration was 0.644 +/- 0.154 mumol/l in children and 0.730 +/- 0.175 mumol/l in adolescents. A large proportion of the individuals (28.43% in the children group, vs 14.05% in adolescent group) exhibited serum selenium levels below 0.57 mumol/l (45 micrograms/l). A significant correlation between serum selenium concentration and age (p < 0.001) was found. The correlation between serum selenium concentration and sex was not significant.

CONCLUSIONS

In comparison with serum selenium levels in children and adolescents from other countries, the concentration of serum selenium in Slovak children and adolescents is relatively low. This differences could probably be attributed to the selenium content in the soil and to the lower average daily selenium intake via food. (Tab. 5, Fig. 2, Ref. 32).

Levels of lipid peroxidation and antioxidants in vegetarians

Age dependence of lipid peroxidation levels estimated as conjugated dienes (CD) of plasma fatty acids was investigated in vegetarian and non-vegetarian males and females aged 11-14, 15-18, 19-39 and 40-60 years. The increase of CD levels with age was found in probands on both types of nutrition up to the age of 40 years. In the first three age groups, lipid peroxidation was insignificantly lower in vegetarians when compared to nonvegetarians. The increase of conjugated dienes was on the level of significance (p < 0.05) in the oldest vegetarians vs nonvegetarians. Therefore, content of defense parameters--antioxidative vitamin and enzyme--was estimated in blood of vegetarians aged 40-60 years. Significantly higher levels of vitamin C and catalase activity were found in vegetarians (C-63.6 and 86.5 mumol/l; CAT-1497 and 1313 U/ml for males and females, respectively) when compared to nonvegetarians (C-41.3 and 54.4 mumol/l; CAT-1192 and 1086 U/ml). A significant negative linear correlation (p < 0.001) for CD-C and CD-CAT was found in both sexes of vegetarians and in nonvegetarian females (p < 0.05 for nonvegetarian males). Important finding is a more pronounced in vegetarians (2.5-3.4 times higher slope of regression lines) indicating positive effect of vegetarian nutrition on efficiency of protection system.

Selected vitamins and trace elements in blood of vegetarians

Selected vitamin (A, C, E, beta-carotene) and trace element (selenium, zinc, copper) levels were estimated in the blood of 67 vegetarian nonsmokers aged 34-60 years. The average period of lacto- or lacto-ovovegetarianism was 6.2 years. The results were compared with those of 75 nonvegetarians of the same age and living in the same region. Vegetarians had significantly higher plasma levels of essential antioxidants: vitamin C, beta-carotene, and vitamin A. A significantly higher molar ratio vitamin E/cholesterol indicates a more effective protection especially of low-density lipoproteins against peroxidation. Oxidation of low-density lipoproteins represents one of the key factors in the pathogenesis of atherosclerosis. The molar ratio vitamin E/total lipids was significantly higher in plasma of vegetarians, demonstrating a more effective protection of polyunsaturated fatty acids against peroxidation. Vegetarians had significantly higher plasma levels of selenium and similar levels of zinc and copper when compared to nonvegetarians. These trace elements are important for the activity of antioxidant enzymes. The results document a beneficial effect of vegetarian nutritional habits on antioxidative parameters and thus on the reduction of cardiovascular diseases and cancer risk. Reactive products of oxygen metabolism and subsequent toxic products of lipid peroxidation play an important role in the etiology of these diseases.

Serum selenium levels in Slovak population

Blood serum selenium levels were measured in 576 healthy middle aged adults (40-60 yr, 255 men and 321 women) residing in both urban and rural areas in four districts of Slovakia. Serum selenium was determined by electrothermal AAS. The mean (+/- SD) serum selenium concentration was 0.852 +/- 0.335 mumol/L, ranging from 0.219-2.30 mumol/L. A large proportion of the individuals (19.62%) exhibited serum selenium levels under 0.57 mumol/L (45 mumol/L). There was no significant correlation between serum selenium concentration and age, sex, and smoking status. There were significant differences between districts. The lowest mean (+/- SD) serum selenium was 0.664 +/- 0.269 mumol/L, the highest mean serum selenium (+/- SD) was 0.975 +/- 0.361 mumol/L. This differences could probably be attributed to the selenium content in the soil of the different areas, which would contribute to the average daily selenium intake. In comparison with serum selenium levels in other European countries, the concentrations of selenium in the Slovak population are relatively low.

[Lipid and pro-oxidative and antioxidative parameters in the blood of vegetarians]

The authors subdued 183 vegetarians to examination, the aim of which was to judge the state of health and nutrition of the vegetarian population. The examined group was composed of people with their age ranging from 19-60 years, out of which 102 were of younger (19-39 years) and 81 were of older age. Their average period of vegetarian food consumption was 4.2 years. One third of men and a half of women were lacto-vegetarians, the rest were lacto-ovo-vegetarians. The results were compared with 160 nonvegetarians (64 of younger and 96 of older age). The detected values of lipid parameters were evaluated as favourable for vegetarians (low values of cholesterol, triacylglycerols, atherogenic index, LDL-cholesterol, the share of HDL-cholesterol was 28-33% (vs 24-26% in nonvegetarians) with values converging to 1.4 mmol.l-1--i.e. reduced risk). Additional favourable factors in prevention of atherosclerosis include the absence of obesity in vegetarians and values of antisclerotic active substances in blood (high values of vitamin C, in comparison with nonvegetarians a significantly higher molar ratio of vitamin E/cholesterol and vitamin E/triacylglycerols--more effective protection against peroxidation of lipids). Vegetarian mode of food consumption may be favourably evaluated regarding prooxidative-antioxidative parameters which play an important role in the process of atherogenesis, and carcinogenesis. Significantly lower values of conjugated dienes in plasma of vegetarians and vice versa high values of antioxidant substances (vitamin C, vitamin E/lipid components, catalase activity) were detected. A more pronounced system of detoxication in vegetarians is important due to a possible risk of an increased intake of xenogenous substances. (Tab. 3, Ref. 27.)

Comparison of selected nutritional indicators in children in Slovakia in 1988 and 1992

Selected indicators of nutritional status in children and adolescents assessed in 1988 and 1992 were compared in relation to changed food consumption trends caused by liberalization of food prices. In 1992, 1507 individuals aged 11-18 years were examined and the results were compared with those of children and adolescents of the same age group examined in 1988. Negative changes in food habits are probably the cause of persisting high levels of serum lipids and increasing frequency of hypoascorbinaemia.

[The present health and nutritional status of the pediatric population in the area of Orava]

410 children aged 11-14 years and 311 adolescents aged 15-18 years were examined in the region Orava. This region was selected for the survey because of high unemployment rates. The survey was focused on changes in nutritional indices in children and adolescents, as a consequence of changed food consumption patterns, caused by increased food prices and global socio-economic regression. Biochemical markers showed negative trends in serum lipid levels, especially a high prevalence of hypercholesterolaemia as well as that of vitamin C hyposaturation. This finding is related to impaired structure of consumed food, intake of food items of lower nutritional value, low intakes of fruit and vegetables, as shown by the analysis of dietary data.