Diet diversity and colorectal cancer

Effects of Continuous Nutrition Care on Nutritional Status and Dietary Habits of Patients With Colorectal Cancer Receiving Adjuvant Chemotherapy After Surgery

Patients with colorectal cancer may experience symptoms such as diarrhea, nausea, and anorexia, during surgery and chemotherapy, which can increase the risk of malnutrition. In addition, dietary habits play a key role in the onset of colorectal cancer; therefore, it is necessary to improve dietary habits to prevent recurrence during treatment after diagnosis. In this study, a clinical nutritionist conducted 4 interviews for patients diagnosed with colorectal cancer and scheduled for colectomy: before surgery, after surgery, 1st chemotherapy, and 2nd chemotherapy, and provided nutrition care for each treatment course to determine its effects on nutrition status and disease prognosis. Significant weight loss but no decrease in muscle mass was observed during treatment. Body fat mass, although not statistically significant, showed a decreasing tendency. The percentage of people who responded 'yes' to the below items increased after compared to before receiving nutrition education: 'I eat meat or eggs more than 5 times a week,' 'I eat seafood at least three times a week,' 'I eat vegetables at every meal,' 'I eat fruits every day,' and 'I eat milk or dairy products every day.' These results indicate that the patients changed their dietary habit from a monotonous eating pattern to a pattern of consuming various food groups after receiving nutrition education. These results suggest that continuous nutrition care by clinical dietitians, according to the patient's treatment process, can help improve the patient's nutritional status and establish healthy eating habits.

An online survey of dietary quality during complementary feeding; associations with maternal feeding self-efficacy and adherence to dietary recommendations

Background

Parents are the gatekeepers of nutrition in early life and their feeding practices form children’s dietary behaviours. Although maternal characteristics have been associated with certain feeding practices, their relationship with overall quality of complementary feeding diets has not been explored. This study aimed to: assess dietary quality in complementary feeding age; explore its association with maternal and child characteristics; and evaluate the association between complementary feeding practices and child weight.

Methods

An online cross-sectional survey captured data from a self-selected sample of mothers living in the UK with a healthy full-term child in complementary feeding age. A total of 466 mothers completed a questionnaire on their complementary feeding practices, demographics, anthropometrics, rates of maternal food neophobia, feeding self-efficacy, social support, postnatal depression and infant temperament. Dietary quality was assessed using the Complementary Feeding Utility Index (CFUI). Children were classified into underweight, normal weight, overweight and obese.

Results

Majority of participants reported high levels of dietary quality as determined by a mean CFUI score of 80%. High dietary quality was associated with reliance on the NHS recommendation on timing of complementary feeding and maternal self-efficacy in promoting a healthy diet and limiting non-recommended foods. Responsive feeding, longer breastfeeding duration, frequent exposure to fruits and to a high variety of protein-rich animal foods were significantly associated with lighter child weight status. Consumption of sweetened drinks and delayed introduction of lumpy foods were associated with heavier child weight status.

Conclusions

This study provided an evaluation of dietary quality in complementary feeding in a UK sample of children and explored its relationship with maternal and child attributes. Increasing understanding of the current complementary feeding recommendations and strengthening maternal feeding self-efficacy may be key for healthcare professionals and researchers to improving complementary feeding practices.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40795-022-00595-8.

Dietary diversity score (DDS) and odds of colorectal cancer and adenoma: a case–control study

Despite mounting evidence that dietary factors might have a protective role against risk of cancer, few studies have assessed the relationship between diet diversity with colorectal cancer (CRC) and colorectal adenoma (CRA). Thus, we examined the relationship between dietary diversity score (DDS) and the odds of CRC and CRA. Overall, 129 CRC diagnosed patients, 130 CRA diagnosed cases and 240 healthy hospitalised controls were studied. DDS was calculated based on information on the usual diet that was assessed by a valid and reliable food frequency questionnaire (FFQ). Multivariate logistic regression was used to estimate the relationship between DDS and odds of colorectal cancer and adenoma. After adjusting for potential confounders, the diversity of grains is associated with the increased odds of CRC (OR_grains: 2·96 (1·05–8·32); P = 0·032), while the diversity of vegetables and fruits are associated with decreased odds of CRC (OR_vegetables: 0·31 (0·16–0·62); P = 0·001, OR_fruits: 0·37 (0·23–0·61); P < 0·001). The diversity of vegetables, fruits and dairy are inversely associated with odds of CRA (OR_vegetables: 0·41 (0·21–0·78); P = 0·007, OR_fruits: 0·58 (0·36–0·93); P = 0·021, OR_dairies: 0·56 (0·37–0·83); P = 0·004). Also, higher DDS was related to decreased odds of both CRC (OR: 0·41 (0·23–0·72); P for trend = 0·002) and CRA (OR: 0·36 (0·21–0·65); P for trend = 0·001). Our results indicated that higher dietary diversity and particularly a diet varied in fruits and vegetables may reduce the odds of CRC and CRA. Also, the consumption of dairy products may decrease the odds of CRC, whereas the consumption of grains may increase the odds of CRC.

Can Oral Tolerance Explain the Inconsistencies Associated with Total Dietary Diversity and Colon Cancer? A Mechanistic Systematic Review

Among the gastrointestinal tract cancers, the risk of colon cancer is strongly dependent on dietary factors. For the first time in the current review, all the original case-control studies, associated with the correlation between total dietary diversity score and colon cancer risk, were evaluated. In this regard, three databases, including PubMed/MEDLINE, Scopus, and Web of Sciences, were investigated to retrieve the related citations from 1990 until 2019. Among the included citations, three studies were finally included. In these included studies, the dietary diversity score was evaluated with 129-item and 800-item FFQs. Findings reveal that total dietary diversity can increase the risk of colon cancer in men, but not women; while, one study using 57-item FFQ reported the beneficial association of total dietary diversity with colon cancer among men. Significant demand for conducting more research to investigate the real mechanistic effects of dietary diversity on the risk of colon cancer development was demonstrated due to the inconsistent, questionable, and incomplete findings associated with the included studies.

The effect of comprehensive intervention for childhood obesity on dietary diversity among younger children: Evidence from a school-based randomized controlled trial in China

Background

Little evidence from developing countries on dietary transition demonstrates the effects of comprehensive childhood obesity interventions on dietary diversity and food variety among younger children. This study aimed to evaluate the effects of comprehensive childhood obesity interventions on dietary diversity among younger children.

Methods

A total of 4846 children aged 7–13 years were included based on a multicenter randomized controlled trial for childhood obesity interventions in 38 primary schools. Nutrition education intervention (NE), physical activity intervention (PA) and comprehensive intervention including both NE and PA (CNP) were carried out separately for 2 semesters. Dietary Diversity Score (DDS9 and DDS28 for 9 and 28 food groupings, respectively), Food Variety Score (FVS, the number of food items) and the proportions of different foods consumed were calculated according to the food intake records collected with the 24-h dietary recall method.

Results

The intervention effects per day of comprehensive intervention group were 0 (95% Confidence Interval (CI): 0, 0.1; p = 0.382) on DDS9, 0.1 (95% CI: -0.1, 0.2; p = 0.374) on DDS28 and 0.1 (95% CI: -0.1, 0.3; p = 0.186) on FVS of overall diet, which was 0.1 (95% CI: 0, 0.1; p < 0.001) on DDS9, 0 (95% CI: 0, 0.1; p = 0.168) on DDS28 and 0.1 (95% CI: 0, 0.1; p = 0.067) on FVS of dietary scores of breakfast only. Additionally, CNP group had greater increases in cereals, meat and fruits, and more decreases in eggs, fish and dried legumes consumption proportions as compared with the control group. Decreasing side effect on dietary diversity and food variety were found for PA intervention, but not for NE intervention only.

Conclusions

Though the comprehensive obesity intervention didn’t improve the overall dietary diversity per day, the positive intervention effects were observed on breakfast foods and some foods’ consumption.

Regulatory T Cells in Bioactive Peptides-Induced Oral Tolerance; a Two-Edged Sword Related to the Risk of Chronic Diseases: A Systematic Review

This systematic review assesses the literature regarding beneficial and potential detrimental effects of bioactive peptides (BPs), focusing on evidence of regulatory T cells (T-regs) mediated oral tolerance (OT), collagen hydrolysate (CH) supplementation in osteoarthritis (OA) and the association of T-regs with chronic disease. The systematic search was done for articles published from inception to April 2019 using the PubMed and Scopus databases. About 3081 papers were identified by three different search strategies and screened against inclusion criteria which resulted in the inclusion of 22 articles. From the included articles, 12 papers were related to treatment of different disease in vivo by oral administration of BPs, six articles evaluated the effects of CH supplementation, as a rich source of BPs, on OA pain-relief and four observational studies assessed the association of circulating T-regs and risk of cancer and cardiovascular disease (CVD). The evidence obtained from first search strategy, indicated that oral administration of BPs improve clinical manifestations of animal models of allergy, arthritis, atherosclerosis, ulcerative colitis and allograft rejection by T-regs expansion; while, observational studies showed that although higher levels of circulating T-regs reduced risk of CVD and allergy, but, increased risk of solid cancers.

Association between dietary diversity and obesity in the Filipino Women's Diet and Health Study (FiLWHEL): A cross-sectional study

Background

Dietary diversity—eating a more varied diet, may be one of the important components of a healthy diet. We aimed to examine whether dietary diversity score was associated with lower prevalence of obesity.

Methods

This is a cross-sectional study of 402 married immigrant participants enrolled in the Filipino Women’s diet and health study (FiLWHEL). Dietary information was obtained using the 24-hour recall method. Anthropometric measurements including height, weight, and waist circumference were directly measured. Dietary diversity score was calculated by summing up the reported number of food groups and additional scores for diversity within food groups were derived. We defined general obesity as body mass index (BMI) of ≥25 kg/m² and abdominal obesity as waist circumference of ≥80 cm. We calculated odds ratios and 95% confidence intervals using the multivariable logistic regression accounting for several potential confounders.

Results

Dietary diversity score was inversely associated with abdominal and general obesity; odds ratios (95% confidence intervals) were 0.49 (0.30–0.82) (p for trend = 0.009) for abdominal obesity and 0.47 (0.28–0.81) (p for trend = 0.008) for general obesity when we compared the third tertile of diversity scores with the first tertile. In the analyses of diversity within food groups, greater diversity in other vegetables was associated with 49% or 50% lower prevalence of abdominal or general obesity, respectively. Furthermore, poultry diversity score was associated with 56% lower prevalence of general obesity.

Conclusion

Our study suggests the evidence that high dietary diversity appears to be related to low prevalence of obesity.

Dietary diversity and nutritional adequacy among married Filipino immigrant women: The Filipino Women's Diet and Health Study (FiLWHEL)

Background

Migration has an influence on health behavior and food intake. Dietary variety is a key component to high-quality diets because a single food item does not contain a variety of nutrients and may not reflect nutritional adequacy. We aimed to compare the dietary diversity scores (DDS), food variety scores (FVS), and nutrient adequacy levels of married Filipino immigrant women in Korea to those of Korean women.

Methods

We matched the data of 474 participants aged 20-57 years from the Filipino Women’s Diet and Health Study (FiLWHEL) by age category with those of married Korean women randomly selected from the Korea National Health and Nutrition Examination Survey (KNHANES). Dietary information in FiLWHEL and KNHANES were assessed through the 24-hour recall method. We calculated the DDS by summing the number of eleven food groups consumed (DDS 10 g if they consumed at least 10 g/day; DDS all if they consumed any amount) and the FVS by counting the number of food items consumed. For nutrient adequacy, we calculated the probability of adequacy (PA) and intake below the estimated average requirement (EAR).

Results

Filipino women had a lower DDS and FVS in comparison to Korean women. The means (±SDs) of DDS 10 g, DDS all, and FVS for Filipino women versus Korean women were 6.0 (±1.6) versus 6.8 (±1.5) (p < 0.001), 6.7 (±1.7) versus 7.9 (±1.4) (p < 0.001) and 9.2 (±3.3) versus 14.7 (±4.9) (p < 0.001), respectively. When we compared each food group, the intakes of fish, other seafood, legumes/seeds/nuts, eggs, vegetables, and fruits were lower for Filipino women than for Korean women. The mean probability of adequacy (MPA) of nutrient intake of the nine selected nutrients was lower for Filipino women in comparison to Korean women. The mean (±SD) was 0.55 (±0.28) versus 0.66 (±0.26), respectively.

Conclusions

Our findings showed that married Filipino immigrant women in Korea had lower dietary variety scores in comparison to Korean women. This was reflected in their nutritional adequacy. Nutrition education focusing on the promotion of eating a variety of foods may be needed for Filipino immigrant women in Korea.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5233-z) contains supplementary material, which is available to authorized users.

Depression is related to dietary diversity score in women: a cross-sectional study from a developing country

BACKGROUND

Substantial evidence provides support for the role of diet in the prevention and control of mental disorders. However, since there is no study regarding the relationship between dietary diversity and stress or depression, we aimed to determine the relationship between the dietary diversity score (DDS) and stress and depression in women.

METHODS

This descriptive-analytical cross-sectional study was performed on 360 women aged 20-49 years attending health centers in the south of Tehran. The dietary intake and score of depression, anxiety, and stress were measured using a 24-h dietary recall and the 42-item depression, anxiety, stress scales questionnaire, respectively. The DDS was calculated based on the FAO 2013 guidelines. Data were analyzed using Chi-square, analysis of variance, Spearman correlation coefficient, and multivariable logistic regression tests.

RESULTS

In total, 31.4 and 25.8% of the subjects suffered from depression and stress, respectively. After adjusting for confounders, a one-unit increase in DDS was associated with a 39% reduction in the risk of severe depression. The DDS was not significantly associated with mild or moderate depression, and no significant relationship was observed between the DDS and stress.

CONCLUSIONS

The DDS could be inversely associated with depression in women. Since we observed no significant relationship between stress and DDS, further studies are needed in this regard.

Traditional Lebanese Recipes Based on Wild Plants: An Answer to Diet Simplification?

Background

The challenge posed by the nutrition transition occurring throughout the world is enormous: rates of chronic disease, particularly overweight and obesity and cardiovascular disease, have reached alarming levels—often occurring in parallel with high levels of micronutrient deficiencies. Lebanon is no exception. And yet this Mediterranean country enjoys a rich biodiversity, with thousands of endemic species and an equally rich culinary history, largely based on its local biodiversity, including wild edible plants.

Objectives

To record traditional Lebanese recipes based on wild edible plants and to investigate their potential to contribute to a more diversified diet.

Methods

A series of nine focus group meetings was conducted with key informants knowledgeable in wild edible plant identification, harvesting, and use.

Results

Common recipes based on wild edible plants were collected and standardized from rural communities where collection of wild edible plants is common. Nutrient analysis and food-composition analysis were performed, including comparisons with processed dishes that are increasingly common in the Lebanese diet, revealing that the wild edible plant-based dishes offered a healthier alternative.

Conclusions

Since traditional recipes often use items from several food groups in one dish, they can be a good model for diet diversification. The promotion of the collection and use of wild edible plants and their derived products can lead to improved nutrition.

Association of dietary diversity score with anxiety in women

Evidence suggests that diet plays an important role in the development of mental disorders, especially anxiety. Dietary diversity score is an indicator for assessing diet quality. However, its association with anxiety has not been investigated. The aim of this study was to examine the association of dietary diversity score with anxiety. A cross-sectional study was conducted among 360 women attending health centers in the south of Tehran in 2014. General information among others were collected. Weight, height and waist circumference were measured and body mass index (BMI) was calculated. Dietary intake and anxiety score were assessed using a 24-h dietary recall and Depression, Anxiety, Stress Scales (DASS) questionnaires, respectively. Dietary diversity score was computed according to the guidelines of FAO. About 35% of the participants were found to exhibit anxiety. The dietary diversity score in 12.5% of the subjects were between 1 and 3 (low dietary diversity score) but 87.5% scored between 4 and 7 (high dietary diversity score). The adjusted mean of anxiety score in subjects with high dietary diversity score was significantly lower than those with low dietary diversity score. Dietary diversity score was found to be inversely associated with anxiety. However, the causality between anxiety and dietary diversity could not be determined.

Subtypes of fruit and vegetables, variety in consumption and risk of colon and rectal cancer in the European Prospective Investigation into Cancer and Nutrition

Previously, a lower risk of colorectal cancer was observed with fruit and vegetable consumption in the European Prospective Investigation into Cancer and Nutrition within a follow-up period of 9 years which was not fully supported by a recent meta-analysis. Therefore, we were interested in the relation with extended follow-up, also focusing on single subtypes and a variety of intake of fruit and vegetables. Fruit and vegetable consumption was assessed at baseline. After an average of 13 years of follow-up, 3,370 participants were diagnosed with colon or rectal cancer. Diet diversity scores were constructed to quantify variety in fruit and vegetable consumption. A lower risk of colon cancer was observed with higher self-reported consumption of fruit and vegetable combined (HR Q4 vs. Q1 0.87, 95% CI 0.75-1.01, p for trend 0.02), but no consistent association was observed for separate consumption of fruits and vegetables. No associations with risk of rectal cancer were observed. The few observed associations for some fruit and vegetable subtypes with colon cancer risk may have been due to chance. Variety in consumption of fruits and vegetables was not associated with a lower risk of colon or rectal cancer. Although a lower risk of colon cancer is suggested with high consumption of fruit and vegetables, this study does not support a clear inverse association between fruit and vegetable consumption and colon or rectal cancer beyond a follow-up of more than 10 years. Attenuation of the risk estimates from dietary changes over time cannot be excluded, but appears unlikely.

Fruit and vegetables and cancer risk: a review of southern European studies

High intakes of fruit and vegetables may reduce the risk of cancer at several sites. Evidence has been derived mainly from case-control studies. We reviewed the relationship between consumption of vegetables and fruit and the risk of several common cancers in a network of Italian and Swiss case-control studies including over 10,000 cases of fourteen different cancers and about 17,000 controls. Data were suggestive of a protective role of vegetable intake on the risk of several common epithelial cancers. OR for the highest compared with the lowest levels of consumption ranged from 0.2 (larynx, oral cavity and pharynx) to 0.9 (prostate). Inverse associations were found for both raw and cooked vegetables, although for upper digestive tract cancers the former were somewhat stronger. Similar inverse associations were found for cruciferous vegetables. Frequent consumption of allium vegetables was also associated with reduced risk of several cancers. Fruit was a favourable correlate of the risk of several cancers, particularly of the upper digestive tract, with associations generally weaker than those reported for vegetables. A reduced risk of cancers of the digestive tract and larynx was found for high consumption of citrus fruit. Suggestive protections against several forms of cancer, mainly digestive tract cancers, were found for high consumption of apples and tomatoes. High intakes of fibres, flavonoids and proanthocyanidins were inversely related to various forms of cancer. In conclusion, data from our series of case-control studies suggested a favourable role of high intakes of fruit and vegetables in the risk of many common cancers, particularly of the digestive tract. This adds evidence to the indication that aspects of the Mediterranean diet may have a favourable impact not only on CVD, but also on several common (epithelial) cancers, particularly of the digestive tract.

Can nutrient profiling help to identify foods which diet variety should be encouraged? Results from the Whitehall II cohort

Higher variety of recommended foods, identified arbitrarily based on dietary guidelines, has been associated with better health status. Nutrient profiling is designed to identify objectively, based on nutrient content, healthier foods whose consumption should be encouraged. The objective was to assess the prospective associations between total food variety (food variety score, FVS) and variety from selected recommended and non-recommended foods (RFV and NRFV, respectively) and risk of chronic disease and mortality. In 1991-3, 7251 participants of the Whitehall II study completed a 127-item FFQ. The FVS was defined as the number of foods consumed more than once a week. (N)RFV(Ofcom) and (N)RFV(SAIN,LIM) were similarly derived selecting healthier (or less healthier) foods as defined by the UK Ofcom and French SAIN,LIM nutrient profile models, respectively. Multi-adjusted Cox regressions were fitted with incident CHD, diabetes, CVD, cancer and all-cause mortality (318, 754, 137, 251 and 524 events, respectively – median follow-up time 17 years). RFV and NRFV scores were mutually adjusted. The FVS (fourth v. first quartile) was associated with a 39 and 26% reduction of prospective CHD and all-cause mortality risk, respectively. The RFV(Ofcom) (third v. first quartile) was associated with a 27 and 35% reduction of all-cause mortality and cancer mortality risk, respectively; similar associations were suggested, but not significant for the RFV(SAIN,LIM). No prospective associations were observed with NRFV scores. The results strengthen the rationale to promote total food variety and variety from healthy foods. Nutrient profiling can help in identifying those foods whose consumption should be encouraged.

Diet quality score is a predictor of type 2 diabetes risk in women: the Australian Longitudinal Study on Women's Health

The present study aimed to determine the ability of two diet quality scores to predict the incidence of type 2 diabetes in women. The study population comprised a nationally representative sample of 8370 Australian middle-aged (45-50 years) women participating in the ALSWH (Australian Longitudinal Study on Women's Health), who were free of diabetes and completed FFQ at baseline. The associations between the Australian Recommended Food Score (ARFS) and Dietary Guideline Index (DGI) with type 2 diabetes risk were assessed using multiple logistic regression models, adjusting for sociodemographic characteristics, lifestyle factors and energy intake. During 6 years of follow-up, 311 incident cases of type 2 diabetes were reported. The DGI score was inversely associated with type 2 diabetes risk (OR comparing the highest with the lowest quintile of DGI was 0·51; 95% CI 0·35, 0·76; P for trend = 0·01). There was no statistically significant association between the ARFS and type 2 diabetes risk (OR comparing the highest with the lowest quintile of ARFS was 0·99; 95% CI 0·68, 1·43; P for trend = 0·42). The results of the present prospective study indicate that the DGI score, which assesses compliance with established dietary guidelines, is predictive of type 2 diabetes risk in Australian women. The risk of type 2 diabetes among women in the highest quintile of DGI was approximately 50% lower than that in women in the lowest quintile. The ARFS was not significantly predictive of type 2 diabetes.

Dietary quality indices vary with sociodemographic variables and anthropometric status among Mexican adults: a cross-sectional study. Results from the 2006 National Health and Nutrition Survey

OBJECTIVE

To evaluate the dietary quality of Mexican adults' diet, we constructed three dietary quality indices: a cardioprotective index (CPI), a micronutrient adequacy index (MAI) and a dietary diversity index (DDI).

DESIGN

Data were derived from the 2006 National Health and Nutrition Survey, which is a national survey representative of the Mexican population with a stratified, multistage, probabilistic sample design. Dietary intake was assessed from an FFQ with 101 different foods and daily nutrient intakes were computed. The CPI evaluated compliance with seven WHO recommendations for the prevention of CVD, the MAI evaluated the intake of six micronutrients based on the estimated average requirements from the US Institute of Medicine and the DDI was constructed based on the consumption of thirty different food groups.

SETTINGS

Mexico.

SUBJECTS

Mexican adults aged 19-59 years old.

RESULTS

We evaluated the diet of 15 675 males and females. Adjusted means and adjusted proportions by age and sex were computed to predict adherence to dietary recommendations. Rural inhabitants, those living in the South and those from the lowest socio-economic status reported a significantly higher CPI (4·5 (se 0·08), 4·3 (se 0·08) and 4·2 (se 0·09), respectively; P < 0·05), but a significantly lower MAI and DDI, compared with urban inhabitants, those from the North and those of upper socio-economic status (P < 0·05).

CONCLUSIONS

The constructed diet quality indices identify nutrients and foods whose recommended intakes are not adequately consumed by the population. Given the epidemiological and nutritional transition that Mexico is experiencing, the CPI is the most relevant index and its components should be considered in Mexican dietary guidelines as well as in any food and nutrition programmes developed.

Does compliance with nutrition guidelines lead to healthy aging? A quality-of-life approach

OBJECTIVES

We aimed to estimate, in a large French cohort of middle-aged adults derived from the Supplémentation en Vitamines et Minéraux Antioxydants trial, the association of compliance with the guidelines of the French Nutrition and Health Program (PNNS) assessed at inclusion and change in health-related quality of life (HRQoL) over 12 years. A secondary objective was to identify the relative contribution of diet and physical activity to long-term change in HRQoL.

DESIGN/SUBJECTS

Subjects were Supplémentation en Vitamines et Minéraux Antioxydants trial participants aged 45 to 60 years at inclusion in the cohort.

MAIN OUTCOME MEASURES

Compliance with nutrition guidelines (diet and physical activity) was assessed by the PNNS Guideline Score (maximum 15 points) at inclusion. HRQoL was measured by the Medical Outcomes Survey Short Form 36 (SF-36) at 1 year (initial measurement) and 13 years (final measurement) after inclusion. The primary end point was change in the SF-36 physical component summary (PCS) and mental component summary (MCS) scores over 12 years.

RESULTS

In total, 3,005 subjects (mean age 51.4 ± 4.3 years) completed the SF-36 at the initial and final measurement. The mean PNNS Guideline Score was 7.8 ± 1.9 and the mean PCS and MCS was 52.2 ± 6.4 and 50.3 ± 7.0, respectively, at the initial measurement and 48.0 ± 9.6 and 51.2 ± 8.7 at the final measurement. Better compliance with nutritional guidelines was associated with better initial and final HRQoL but not associated with change in HRQoL. Compliance with dietary guidelines was associated with positive change in PCS score but not associated with initial PCS score. In contrast, compliance with dietary guidelines was related to positive initial MCS score but not related to change in MCS score. Compliance with physical activity guidelines was related to initial PCS and MCS scores but not related to change in PCS and MCS scores.

CONCLUSIONS

Following physical activity guidelines may be associated with better concomitant HRQoL and following dietary guidelines with better future physical HRQoL.

Food variety at 2 years of age is related to duration of breastfeeding

The aim of this study was to investigate the association of breastfeeding duration and food variety at 2 years of age. A secondary data analysis was undertaken of the Western Australian Pregnancy Cohort (Raine) Study, an ongoing longitudinal study. Data collected from a single 24 h dietary recall of 1905, 2 year-old children were used to calculate two food variety scores; a core food variety score (CFVS) and a fruit and vegetable variety score (FVVS). Multivariate linear regression analysis was used to identify those factors independently associated with the CFVS and FVVS. The mean CFVS was 7.52 (range 1–18) of a possible 34 food items or groups and the mean FVVS was 2.84 (range 0–10) of a possible 16 food items or groups. Breastfeeding duration was independently directly associated with the CFVS (p < 0.001) and FVVS (p < 0.001). In addition, maternal age was independently directly associated with the CFVS (p < 0.001) and FVVS (p = 0.001) as was maternal education (CFVS p < 0.001 and FVVS p = 0.043). The presence of older siblings was independently inversely associated with the CFVS (p = 0.003) and FVVS (p = 0.001). This study demonstrated a direct modest association between breastfeeding duration and food variety in 2 year-old children, independent of maternal demographic characteristics known to predict food variety in children. This finding supports the hypothesis that flavours transferred in breast milk provide repeated early exposure to different tastes and positively shape children’s food preferences and food variety.

Recent trends in colorectal cancer mortality in Europe

Colorectal cancer mortality has been declining over the last two decades in Europe, particularly in women, the trends being, however, different across countries and age groups. We updated to 2007 colorectal cancer mortality trends in Europe using data from the World Health Organization (WHO). Rates were analyzed for the overall population and separately in young, middle-age and elderly populations. In the European Union (EU), between 1997 and 2007 mortality from colorectal cancer declined by around 2% per year, from 19.7 to 17.4/100,000 men (world standardized rates) and from 12.5 to 10.5/100,000 women. Persisting favorable trends were observed in countries of western and northern Europe, while there were more recent declines in several countries of eastern Europe, including the Czech Republic, Hungary and Slovakia particularly in women (but not Romania and the Russian Federation). In 2007, a substantial excess in colorectal cancer mortality was still observed in Slovakia, Hungary, Croatia, the Czech Republic and Slovenia in men (rates over 25/100,000), and in Hungary, Norway, Denmark and Slovakia in women (rates over 14/100,000). Colorectal mortality trends were more favorable in the young (30-49 years) from most European countries, with a decline of ∼2% per year since the early 1990s in both men and women from the EU. The recent decreases in colorectal mortality rates in several European countries are likely due to improvements in (early) diagnosis and treatment, with a consequent higher survival from the disease. Interventions to further reduce colorectal cancer burden are, however, still warranted, particularly in eastern European countries.

Variety in fruit and vegetable consumption and the risk of lung cancer in the European prospective investigation into cancer and nutrition

BACKGROUND

We investigated whether a varied consumption of vegetables and fruits is associated with lower lung cancer risk in the European Prospective Investigation into Cancer and Nutrition study.

METHODS

After a mean follow-up of 8.7 years, 1,613 of 452,187 participants with complete information were diagnosed with lung cancer. Diet diversity scores (DDS) were used to quantify the variety in fruit and vegetable consumption. Multivariable proportional hazards models were used to assess the associations between DDS and lung cancer risk. All models were adjusted for smoking behavior and the total consumption of fruit and vegetables.

RESULTS

With increasing variety in vegetable subgroups, risk of lung cancer decreases [hazard ratios (HR), 0.77; 95% confidence interval (CI), 0.64-0.94 highest versus lowest quartile; P trend = 0.02]. This inverse association is restricted to current smokers (HR, 0.73; 95% CI, 0.57-0.93 highest versus lowest quartile; P trend = 0.03). In continuous analyses, in current smokers, lower risks were observed for squamous cell carcinomas with more variety in fruit and vegetable products combined (HR/two products, 0.88; 95% CI, 0.82-0.95), vegetable subgroups (HR/subgroup, 0.88; 95% CI, 0.79-0.97), vegetable products (HR/two products, 0.87; 95% CI, 0.79-0.96), and fruit products (HR/two products, 0.84; 95% CI, 0.72-0.97).

CONCLUSION

Variety in vegetable consumption was inversely associated with lung cancer risk among current smokers. Risk of squamous cell carcinomas was reduced with increasing variety in fruit and/or vegetable consumption, which was mainly driven by the effect in current smokers.

IMPACT

Independent from quantity of consumption, variety in fruit and vegetable consumption may decrease lung cancer risk.

Risk of colorectal cancer in relation to frequency and total amount of red meat consumption. Systematic review and meta-analysis

INTRODUCTION

The colon and rectum are common sites of food-related cancer in developed countries. Recent studies strongly suggest that red meat intake is associated with colon cancer, whereas for rectal cancer such an association still needs to be proved. The aim of the study was to assess the role of total amount and frequency of red meat intake in colorectal carcinogenesis based on published data using meta-analysis methods.

MATERIAL AND METHODS

The literature published until 2009 was selected from: MEDLINE, PubMed, Scopus, Embase, CancerLit, Google Scholar and Cochrane Library databases. The used search terms were: colorectal cancer, colon cancer, rectal cancer, meat intake, red meat intake, red meat consumption, meat consumption, colorectal cancer risk, colon cancer risk, rectal cancer risk and lifestyle. Articles investigating red meat intake of more often than once a day or 50 g per day were reviewed and selected for further analysis.

RESULTS

Twenty-two studies fulfilled the established criteria. A meta-analysis confirmed the carcinogenic effect of the consumption of over 50 g of red meat per day for the colon (relative risk 1.21, 1.07-1.37) but not for the rectum (relative risk 1.30, 0.90-1.89). Red meat intake more frequently than once a day can induce both colonic (relative risk 1.37, 1.09-1.71) and rectal cancer (relative risk 1.43, 1.24-1.64).

CONCLUSIONS

Red meat intake is associated with elevated risk of developing colorectal cancer. The frequency of red meat consumption rather than total amount of consumed meat is associated with a higher risk of colorectal carcinogenesis.

Dietary diversity score is related to obesity and abdominal adiposity among Iranian female youth

Objective

To assess the relationship between diet and disease, consideration of whole-diet indices may be more informative than single-nutrient intake. The present study was conducted to report the relationship among dietary diversity score (DDS), obesity and abdominal adiposity among female university students.

Design

Cross-sectional study.

Setting

Isfahan, Iran.

Subjects

A representative sample of 289 healthy female students aged 18–28 years was selected randomly from Isfahan University of Medical Sciences, Iran. Usual dietary intake was assessed using a validated semi-quantitative FFQ. DDS was calculated according to the scoring of the five food groups based on the US Department of Agriculture Food Guide Pyramid. This is a score of diet variety, and shows the diversity of the consumed diet. Participants were categorised on the basis of quartile cut-off points of DDS. Potential confounders such as age, total energy intake and physical activity were considered in all the analyses.

Results

The means (sd) of BMI and waist circumference were 25·9 (sd 5·1) kg/m2 and 85·5 (sd 14) cm, respectively. The probability of obesity decreased with quartiles of DDS (OR among quartiles: 1·00, 0·41, 0·31 and 0·21, P = 0·03; this was the same for abdominal adiposity: 1·00, 0·55, 0·36 and 0·21, P = 0·02). Those in the lowest quartile of the DDS had the highest risk for being overweight.

Conclusions

There were inverse associations among DDS, obesity and abdominal adiposity among the female students of Isfahan University. Further prospective investigations are needed to confirm this finding.

Diet quality – what is it and does it matter?

Objective

Measures of diet quality have evolved with a number of scoring indices currently in use. They are increasingly being used to examine epidemiological associations between dietary intake and nutrition-related health outcomes. The present review aims to describe current diet quality tools and their applications, and to examine the relationship between diet quality and morbidity and mortality.

Design

A search was conducted of MEDLINE, Cochrane, EMBASE, CINAHL and ProQuest electronic databases. Inclusion criteria were: English language; published from 2004 on; conducted in adult populations; longitudinal/cohort/case–control or cross-sectional study; included a theoretically defined measure of diet quality.

Results

A total of twenty-five indices of overall diet quality and/or variety were found, with components ranging from nutrients only to adherence to recommended food group servings, to variety within healthful food groups. The majority of studies reviewed had methodological weaknesses but demonstrated that higher dietary quality was consistently inversely related to all-cause mortality, with a protective effect of moderate magnitude. The associations were stronger for men and for all-cause and CVD mortality.

Conclusions

The limitations of both the indices and the studies that use them need to be considered when interpreting and comparing results. However, diet quality indices do appear to be able to quantify risk of some health outcomes, including biomarkers of disease and risk of CVD, some cancers and mortality. Further research is needed to improve the validity of these tools and to adapt them for use in clinical dietetic practice.

Breast cancer risk in relation to the joint effect of BRCA mutations and diet diversity

It has been suggested that gene-environment interaction is related to the risk of cancer. To evaluate departure from multiplicative effects between BRCA mutations and diet diversity in breast cancer (BC), a case-only study was carried out in a French-Canadian population including 738 patients with incident primary BC comprising 38 BRCA mutation carriers. Diet diversity was assessed using a validated food frequency questionnaire. Unconditional logistic regression analysis was performed to assess case-only odds ratio (COR) and 95% confidence interval (CI) while adjusting for age, body mass index, smoking, hormonal replacement therapy, and total energy intake. Ours results reveal a strong and significant interaction between BRCA mutations and vegetable and fruit diversity (COR = 0.27; 95%CI = 0.10-0.80; P = 0.03) when comparing the upper to the lower quartiles. The estimates for departure from multiplicative effects between BRCA mutations and total or other food groups' diversity were not supportive of the idea of a gene-environment interaction. The results of this study suggest that the combination of BRCA mutations and vegetable and fruit diversity may be associated with a reduced risk of BC.

Biological diversity, dietary diversity, and eye health in developing country populations: establishing the evidence-base

Human and ecosystem health converge around biological diversity issues. Cultivated and wild plants as food and medicine make essential contributions to human health, which in turn provides rationales for conservation. While wild and cultivated plant diversity reasonably facilitates dietary diversity and positive health outcomes, the challenges of demonstrating this relationship limit its impact in concept, policy, and practice. We present a rationale for testing the dietary contribution of biological diversity to improved eye health as a case study based on existing phytochemical, pharmacological, and clinical knowledge. We consider the empirical evidence needed to substantiate, interpret, and apply this relationship at a population and ecosystem level within a unified research framework. Epidemiological data strongly support the prevention of childhood vitamin A deficiency blindness, cataract, and age-related macular degeneration by fruit and vegetable consumption. Phytonutrients, including the carotenoids lutein and zeaxanthin, protect the eye from oxidative stress and harmful light exposure. Laboratory, community, and population level research should prioritize food composition of dietary plants from both agriculture and the wild. Intervention studies, focus groups, and transmission of knowledge of local species and varieties within communities will further interpretation of epidemiological data. Population-based studies combining clinical data and measures of access and consumption of biological diversity are key to demonstrating the important relationships among biodiversity, dietary diversity, and health outcomes.

Adherence to the USDA Food Guide, DASH Eating Plan, and Mediterranean dietary pattern reduces risk of colorectal adenoma

The 2005 Dietary Guidelines for Americans include quantitative recommendations for 2 eating patterns, the USDA Food Guide and the Dietary Approaches to Stop Hypertension (DASH) Eating Plan, to promote optimal health and reduce disease risk. A Mediterranean dietary pattern has also been promoted for health benefits. Our objective was to determine whether adherence to the USDA Food Guide recommendations, the DASH Eating Plan, or a Mediterranean dietary pattern is associated with reduced risk of distal colorectal adenoma. In the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, men and women aged 55-74 y were screened for colorectal cancer by sigmoidoscopy at 10 centers in the U.S. After adjusting for potential confounders, men who most complied with the USDA Food Guide recommendations had a 26% reduced risk of colorectal adenoma compared with men who least complied with the recommendations (OR USDA score >or= 5 vs. <or=2 = 0.74, 95% CI = 0.64-0.85; P-trend < 0.001). Comparable results were found for men who had intakes most similar to the DASH Eating Plan or a Mediterranean dietary pattern. Women who most complied with the USDA Food Guide recommendations had an 18% reduced risk for colorectal adenoma, but subgroup analyses revealed protective associations only for current smokers (OR USDA score >or= 5 vs. <or=2 = 0.52, 95% CI = 0.31-0.89; P-trend < 0.01) or normal-weight women (OR USDA score >or= 5 vs. <or=2 = 0.74, 95% CI = 0.55-0.99; P-trend = 0.08). Following the current U.S. dietary recommendations or a Mediterranean dietary pattern is associated with reduced risk of colorectal adenoma, especially in men.

A critical review of predefined diet quality scores

The literature on predefined indexes of overall diet quality is reviewed. Their association with nutrient adequacy and health outcome is considered, but our primary interest is in the make-up of the scores. In total, twenty different indexes have been reviewed, four of which have gained most attention, and many others were based on those four. The various scores differ in many respects, such as the items included, the cut-off values used, and the exact method of scoring, indicating that many arbitrary choices have been made. Correlations in intake between dietary components may not be adequately addressed. In general, diet quality scores show an association with mortality or disease risk, but these relations are generally modest. Existing indexes do not predict morbidity or mortality significantly better than individual dietary factors. Although conclusions from the review may provide guidance in the construction of a diet quality score, it is questionable whether a dietary score can be obtained that is a much better predictor of health outcome.

Determinants of variation in food cost and availability in two socioeconomically contrasting neighbourhoods of Hamilton, Ontario, Canada

This study addresses links between economic and nutritional variation in an urban North American setting. We employed a mixed-methods approach including mapping, semi-structured interviews, and food outlet surveys to investigate the public health impact of variation in the cost and availability of food between two socioeconomically distinct neighbourhoods of the City of Hamilton, Ontario, Canada. Food cost in supermarkets was not found to be higher in the low-income neighbourhood, though it was much higher in the variety stores that predominate in the low-income neighbourhood. Moreover, there was a very low availability of produce in the variety stores. Reduced fresh produce availability and lower incomes have the potential to negatively influence public health in the less-affluent study area by increasing the difficulty of acquiring healthy foods.

Dietary diversity score and cardiovascular risk factors in Tehranian adults

AIM

To evaluate the relationship between dietary diversity score (DDS) and cardiovascular risk factors in Tehranian adults.

METHODS

In this population-based cross-sectional study, a representative sample of 581 subjects (295 males and 286 females) aged over 18 years, residents of Tehran, participated. Hypercholesterolaemia, hypertriglyceridaemia and low high-density lipoprotein cholesterol were defined according to the Adult Treatment Panel III guidelines of the National Cholesterol Education Program. Diabetes was defined as fasting plasma glucose concentration > or = 126 mg dl(-1) or 2-h post challenge glucose concentration > or = 200 mg dl(-1). Hypertension was defined on the basis of the sixth report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure. Dietary diversity was defined according to the Diet Quality Index revised.

RESULTS

Mean (+/- standard deviation) DDS was 6.15 +/- 1.02. The probability of having diabetes (odds ratio (OR) among quartiles: 1.45, 1.26, 1.11 and 1.00, respectively; P for trend = 0.04) and hypertriglyceridaemia (OR = 1.41, 1.23, 1.05 and 1.00, respectively; P for trend=0.04) decreased with increasing quartile of the diversity score for whole grains. The probability of having obesity (OR among quartiles: 1.39, 1.06, 1.03 and 1.00, respectively; P for trend = 0.03), hypercholesterolaemia (OR = 1.46, 1.28, 1.11 and 1.00, respectively; P for trend = 0.03), hypertension (OR = 1.32, 1.17, 1.13 and 1.00, respectively; P for trend = 0.03) and high low-density lipoprotein cholesterol (LDL-C) (OR = 1.25, 1.12, 1.07 and 1.00, respectively; P for trend = 0.04) decreased with increasing quartile of the diversity score for vegetables. The probability of having hypercholesterolaemia, high LDL-C, hypertension and diabetes decreased with quartile of the DDS. But the probability of being obese increased with quartile of the DDS (P for trend = 0.03).

CONCLUSION

DDS was inversely associated with cardiovascular risk factors in this cross-sectional study. Increased diversity scores of diets, to increase the variety score for vegetables, may be emphasised in programmes attempting to bring about changes in lifestyle.

Dietary diversity score is favorably associated with the metabolic syndrome in Tehranian adults

OBJECTIVE

Assessing overall diet instead of the effects of a single nutrient on diet-disease relations may be more informative. This study was conducted to evaluate the relationship between dietary diversity score (DDS) and metabolic syndrome in Tehranian adults.

DESIGN

Cross-sectional study.

SUBJECTS

A representative sample of 581 healthy subjects aged over 18 y selected randomly from among participants of the Tehran Lipid and Glucose Study.

MEASUREMENTS

Usual dietary intake was assessed using a validated semi quantitative food frequency questionnaire. DDS was calculated based on scoring to the five-food group. The DDS range was 0-10. Weight and height were measured according to standard protocols and body mass index (BMI) was calculated. Fasting blood samples were taken for biochemical measurements and blood pressure was assessed according to standard methods. Metabolic syndrome was defined according to ATPIII. Subjects were categorized based on quartile cut-points of DDS.

RESULTS

Means (+/-s.d.) of age and BMI were 37+/-12 y and 25.7+/-4.3 kg/m(2), respectively. Mean (+/-s.d.) of DDS was 6.15+/-1.02. The probability of having metabolic syndrome decreased with quartiles of DDS (odds ratios among quartiles: 1.00, 0.82, 0.76, 0.70, P<0.05, and odds ratios among quartiles after further adjustment for BMI: 1.00, 0.88, 0.80, 0.77, P<0.05). After controlling for confounders, a significantly decreasing trend was observed for the risk of having high blood pressure, impaired glucose homeostasis and high triglyceride levels.

CONCLUSION

DDS had inverse association with metabolic syndrome and some of its features in this cross-sectional study. A higher dietary diversity, therefore, might be associated with lower possibility of having some metabolic disorders.

Dietary patterns and health outcomes

A systematic review of the literature on dietary patterns (multiple dietary components operationalized as a single exposure) in relation to nutrient adequacy, lifestyle and demographic variables, and health outcome was conducted. Most of the published reports on the subject have used one of two methods to determine dietary patterns: (a) diet indexes or scores that assess compliance with prevailing dietary guidance as dietary patterns, and (b) data-driven methods that use factor or cluster analysis to derive dietary patterns. Irrespective of the approach used, patterns characterized by fruit/vegetable/whole grain/fish/poultry consumption generally have been reported to relate to micronutrient intake, and to selected biomarkers of dietary exposure and disease risk in the expected direction. Age, income, and education have been reported to be among positive predictors of the so-called more healthful dietary patterns. An inverse association of healthful dietary patterns with all-cause mortality and cardiovascular disease risk was reported in most studies. However, the magnitude of risk reduction was modest and was attenuated after control for confounders. Few published studies showed an association between risk of most incident cancers and dietary patterns. Both of the currently used approaches for extracting dietary patterns have limitations, are subject to dietary measurement errors, and have not generated new diet and disease hypotheses.

Pizza and risk of acute myocardial infarction

OBJECTIVES

Pizza eating has been favourably related to the risk of cardiovascular disease, but the data are limited. To evaluate the potential role of pizza consumption on the risk of acute myocardial infarction (AMI), we considered data from an Italian study.

DESIGN

We conducted a hospital-based case-control study on 507 cases of nonfatal AMI and 478 controls in Milan, Italy, between 1995 and 1999.

RESULTS

The multivariate odds ratios were 0.78 for occasional, 0.62 for regular and 0.44 for frequent eaters. The estimates were similar across strata of age, sex, smoking and other major covariates.

CONCLUSIONS

Some of the ingredients of pizza have been shown to have a favourable influence on the risk of cardiovascular disease. However, there is no single explanation for the present findings. Pizza may in fact represent a general indicator of Italian diet, that has been shown to have potential cardiovascular benefits.

Reports: Quantity and Variety of Fruit and Vegetable Consumption and Cancer Risk

The recommendation for fruit and vegetable intake includes eating a certain quantity as well as a variety. The evidence for eating a variety is limited. We examined the association with cancer in a prospective cohort study among 730 Dutch men aged 65-84 yr followed for 10 years, resulting in 138 cancer cases. The quantity of fruits and vegetables was assessed using a dietary history and the variety in intake was based on a food frequency questionnaire. Adherence to the recommended amounts of fruit and vegetables was inversely associated with total cancer risk: The adjusted relative risk (RR) was 0.56 [95% confidence interval (CI) = 0.31-1.00]. Eating the recommended daily 200 g of vegetables was not related to cancer incidence, whereas eating the recommended 200 g of fruit was associated with a 38% lower risk. Variety in vegetable intake was inversely associated with total cancer and non-lung epithelial cancer: The RRs (95% CI) for the highest and lowest tertiles were 0.64 (0.43-0.95) and 0.51 (0.27-0.97), respectively. Only after excluding the first two years of follow-up, variety in fruit intake was associated with reduced cancer risk. In conclusion, adherence to the guidelines for fruit and vegetable intake was associated with lower cancer risk. Besides quantity, variety in intake is also of importance.

Effect of diet, life style, and other environmental/chemopreventive factors on colorectal cancer development, and assessment of the risks

This review presents a comprehensive, evenhanded evaluation of the evidence from experimental, in vitro and human studies associating environmental and therapeutic factors with risk of colorectal cancer. Life styles correlated with the greatest increase in colorectal cancer risk are the ones that typify a diet rich in fat and calories, alcohol drinking and tobacco smoking, and low intake of vegetable, fruits and fibers, referred to as a "western diet," as well as sedentary style (i.e., no- or low-exercise). This kind of life style has also been associated with other chronic diseases (other cancers, obesity, dyslipedemia, diabetes, hypertension cardiovascular, and hypertension). The evidence does not implicated red meat as a risk factor, and fiber has been shown to protect against colorectal adenomas and carcinomas. Calcium, vitamin D, folate, and some antioxidant vitamins and minerals (gamma-tocopherol and selenium) have protective effects, and daily exercise for > or =30 min results in a significant decrease in risk. Estrogen use (hormone replacement therapy) substantially reduces colorectal cancer risk in postmenopausal women. Nonsteroidal anti-inflammatory drugs (e.g., aspirin) in excessive doses is protective, especially in high risk populations, but the side effects of its use and cost incurred due to its continued intake over long periods must be carefully scrutinized before any recommendations are made for the general public.

The association of the school food environment with dietary behaviors of young adolescents

OBJECTIVES

We examined the association between young adolescents' dietary behaviors and school vending machines, à la carte programs, and fried potatoes' being served at school lunch.

METHODS

Using a cross-sectional study design, we measured à la carte availability and the number of school stores, vending machines, and amounts of fried potatoes served to students at school lunch in 16 schools. Grade 7 students (n = 598) completed 24-hour dietary recall interviews.

RESULTS

A la carte availability was inversely associated with fruit and fruit/vegetable consumption and positively associated with total and saturated fat intake. Snack vending machines were negatively correlated with fruit consumption. Fried potatoes' being served at school lunch was positively associated with vegetable and fruit/vegetable intake.

CONCLUSIONS

School-based programs that aim to promote healthy eating among youths should target school-level environmental factors.

Fruit, vegetables, and the prevention of cancer: research challenges

OBJECTIVE

A great deal of epidemiologic evidence has indicated that fruits and vegetables are protective against numerous forms of cancer. However, there are many gaps in our knowledge.

METHODS

In this pilot study we reviewed more than 200 cohort and case-control studies to determine the shape of the dose-response relationship (i.e., how the risk reduction per extra serving of fruits and vegetables changes with the actual intake of these foods). We found major barriers to investigating this. As part of this pilot study we also investigated whether specific fruits and vegetables are responsible for the anticancer action of these foods or whether a wide variety is required for optimal protection. If the former is correct, then fruits and vegetables may contain one or a small number of "magic bullets"; if the latter is correct, then a "teamwork" concept may be valid.

RESULTS

Different findings suggested that the teamwork concept is much more likely. Many studies, especially older ones, have ignored potential confounding variables such as energy intake, alcohol consumption, physical activity, body mass index, smoking, and socioeconomic status (although many recent studies have adjusted for education). Other potential confounders that have generally been ignored are consumption of whole grain cereals and the use of vitamin and mineral supplements.

CONCLUSIONS

The inverse association between intake of fruits and vegetables and the risk of cancer of the colon, breast, and stomach has generally been much stronger in case-control than in cohort studies. We have no clear explanation for this.

Let the pyramid guide your food choices: capturing the total diet concept

This paper discusses how the guideline "Eat a variety of foods" became "Let the Pyramid guide your food choices," presents background information on the food guidance system upon which the Food Guide Pyramid is based and reviews methods that have been used to assess aspects of the total diet, i.e., the variety, moderation and proportionality, promoted by this guidance. The methods include measures of dietary variety, patterns based on Pyramid food group intakes and scoring methods comprised of multiple dietary components. Highlights of results from these methods include the following. Although approximately one third of the U.S. population eat at least some food from all Pyramid food groups, only approximately 1-3% eat the recommended number of servings from all food groups on a given day. Fruits are the most commonly omitted food group. Vegetables and meat are the groups most commonly met by adults, and dairy the most commonly met by youth. Intakes of specific types of vegetables (i.e., dark green, deep yellow) and of grains (i.e., whole grains) are well below that recommended; intakes of total fat and added sugars exceed current recommendations. Scoring methods show those diets of the majority of the population require improvement, and that diets improve with increases in education and income. This paper also discusses the limitations and strengths of these approaches, and concludes with suggestions to improve current food guidance and methods to assess the total diet.