A Dietary Supplement Frequency Questionnaire Correctly Ranks Nutrient Intakes in US Older Adults When Compared to a Comprehensive Dietary Supplement Inventory.

BACKGROUND: Dietary supplements are commonly taken by adults in the United States and can contribute substantially to daily nutrient intakes. Short supplement-use questionnaires are often used in dietary surveys, but their accuracy has not been well studied. OBJECTIVES: The primary objective was to evaluate the accuracy of a short, self-administered supplement frequency questionnaire (SFQ) relative to a comprehensive 1-y inventory of supplement use. A secondary objective was to compare SFQ responses for participants in the intensive measurement study to those from a control group to investigate a possible research participation effect. METHODS: The Supplement Reporting study enrolled 1029 older adults in 2005-2006, with a mean age of 67.8 y, who participated in the Multiethnic Cohort and reported regular use of dietary supplements. Of these, 375 were interviewed quarterly to collect detailed information on types and amounts of dietary supplements used, while 654 served as the control group. All participants completed 2 SFQs, 1 y apart. RESULTS: Agreement between the 2 instruments in use at least weekly ranged from 88% to 97% for 15 of 16 supplement types, with a lower agreement of 74% for vitamin D. The correlations of nutrient intakes from supplements between the 2 instruments were high, ranging from 0.48 to 0.75, except for iron (r = 0.29). However, mean nutrient intakes as reported on the SFQ were higher than intakes from the inventory for most nutrients, sometimes twice as high. Nutrient intakes based on the SFQ were similar for the inventory and control groups, at both baseline and the end of the study. CONCLUSIONS: A self-administered short SFQ can be used in large surveys to identify participants who use 16 categories of dietary supplements at least once a week and can correctly rank participant intakes of nutrients. However, the SFQ does not accurately estimate absolute levels of nutrient intakes from supplements.

Determining minimum food intake amounts for diet diversity scores to maximize associations with nutrient adequacy: an analysis of schoolchildren's diets in rural Kenya.

OBJECTIVE: To explore multiple methods of calculating diet diversity scores (DDS) to maximize associations with predicted dietary micronutrient adequacy among schoolchildren in rural Kenya. DESIGN: Up to three 24 h recall interviews were administered for each child for a total of 1544 d of intake from all schoolchildren. Daily amounts of food consumed were assigned to one of eight food groups. Five DDS were developed based on various minimum intake amounts from each food group: (i) 1 g; (ii) 15 g; (iii) a variable minimum based on the content of a target nutrient for each group; (iv) the median intake level for each group; and (v) the 90th percentile intake level for each group. A diet was assigned 1 point towards the daily DDS if the food group intake was above the defined minimum level. Five scores were calculated for each child, and bivariate longitudinal random-effects models were used to assess the correlation between each DDS and the mean probability of adequacy for fourteen nutrients. SETTING: Embu District, Kenya. SUBJECTS: Schoolchildren (n 529), mean age 7·00 (sd 1·41) years. RESULTS: Only DDS based on a 15 g minimum and DDS based on nutrient content were significantly associated with mean probability of adequacy after adjusting for energy intake (0·21 and 0·41, respectively). CONCLUSIONS: A DDS using minimum intakes based on nutrients contributed by a food group best predicted nutrient adequacy in this population. These analyses contribute to the continued search for simpler and more valid dietary quality indicators among low-income nations.

Dietary choline and betaine intakes vary in an adult multiethnic population.

Choline and betaine are important nutrients for human health, but reference food composition databases for these nutrients became available only recently. We tested the feasibility of using these databases to estimate dietary choline and betaine intakes among ethnically diverse adults who participated in the Multiethnic Cohort (MEC) Study. Of the food items (n = 965) used to quantify intakes for the MEC FFQ, 189 items were exactly matched with items in the USDA Database for the Choline Content of Common Foods for total choline, choline-containing compounds, and betaine, and 547 items were matched to the USDA National Nutrient Database for Standard Reference for total choline (n = 547) and 148 for betaine. When a match was not found, choline and betaine values were imputed based on the same food with a different form (124 food items for choline, 300 for choline compounds, 236 for betaine), a similar food (n = 98, 284, and 227, respectively) or the closest item in the same food category (n = 6, 191, and 157, respectively), or the values were assumed to be zero (n = 1, 1, and 8, respectively). The resulting mean intake estimates for choline and betaine among 188,147 MEC participants (aged 45-75) varied by sex (372 and 154 mg/d in men, 304 and 128 mg/d in women, respectively; P-heterogeneity < 0.0001) and by race/ethnicity among Caucasians, African Americans, Japanese Americans, Latinos, and Native Hawaiians (P-heterogeneity < 0.0001), largely due to the variation in energy intake. Our findings demonstrate the feasibility of assessing choline and betaine intake and characterize the variation in intake that exists in a multiethnic population.

Meat supplementation increases arm muscle area in Kenyan schoolchildren.

The present study examines the effect of animal-source-food (ASF) intake on arm muscle area growth as part of a larger study examining causal links between ASF intake, growth rate, physical activity, cognitive function and micronutrient status in Kenyan schoolchildren. This randomised, controlled feeding intervention study was designed with three isoenergetic feeding interventions of meat, milk, and plain traditional vegetable stew (githeri), and a control group receiving no snack. A total of twelve elementary schools were randomly assigned to interventions, with three schools per group, and two cohorts of 518 and 392 schoolchildren were enrolled 1 year apart. Children in each cohort were given feedings at school and studied for three school terms per year over 2 years, a total of 9 months per year: cohort I from 1998 to 2000 and cohort II from 1999 to 2001. Food intake was assessed by 24 h recall every 1-2 months and biochemical analysis for micronutrient status conducted annually (in cohort I only). Anthropometric measurements included height, weight, triceps skinfold (TSF) and mid-upper-arm circumference (MUAC). Mid-upper-arm muscle area (MAMA) and mid-upper-arm fat area (MAFA) were calculated. The two cohorts were combined for analyses. The meat group showed the steepest rates of gain in MUAC and MAMA over time, and the milk group showed the next largest significant MUAC and MAMA gain compared with the plain githeri and control groups (P< 0.05). The meat group showed the least increase in TSF and MAFA of all groups. These findings have implications for increasing micronutrient intake and lean body mass in primary schoolchildren consuming vegetarian diets.

A school-based supplementary food programme in rural Kenya did not reduce children's intake at home.

OBJECTIVE: To examine changes in energy intake along with markers of dietary quality (animal-source energy and protein intakes) among household members in the presence of supplementary school feeding in rural Kenya. DESIGN: A 2-year, longitudinal, randomized controlled feeding intervention study. SETTING: Kyeni South Division, Embu District, Kenya. SUBJECTS: A total of 182 schoolchildren and selected household members. RESULTS: There was no evidence that schoolchildren who received supplementary snacks at school experienced reduced intakes at home or that intakes by other family members were increased at the expense of the schoolchild's intake. CONCLUSIONS: This analysis highlights a number of factors useful in planning for supplementary feeding interventions in rural Kenya and similar communities.

Validation and Comparison of Nutrient Intakes from Two Dietary Questionnaires Developed for the Multiethnic Cohort Study.

BACKGROUND: Quantitative food frequency questionnaires (QFFQs) are often used to measure dietary intakes in large cohort studies but the impact of updating these questionnaires over time is not often examined. OBJECTIVE: This study compared nutrient intakes estimated from two different QFFQs to each other and to intakes calculated from three 24-hour dietary recalls (24HDRs). DESIGN: This study used a cross-sectional design. PARTICIPANTS/SETTING PARTICIPANTS: Participants (N = 352) were members of the Multiethnic Cohort Study from five racial and ethnic groups (African American, Japanese American, Latino American, Native Hawaiian, and White) who lived in Hawaii and Los Angeles. They were recruited in 2010 and asked to complete two QFFQs, two months apart, and three 24HDRs in the time between completion of the QFFQs. One questionnaire had been developed for a baseline survey (baseline QFFQ) at the start of the Multiethnic Cohort Study during 1993-1996, and the other was updated for a follow-up study 10 years later (10-year QFFQ). MAIN OUTCOME MEASURES: Daily intakes of energy and nine nutrients were estimated from both QFFQs, and from the average of three 24HDRs. STATISTICAL ANALYSES PERFORMED: Pearson's correlation coefficients were calculated between log-transformed nutrient intakes from each QFFQ and the 24HDRs and between the two QFFQs overall, by sex, and by race and ethnicity. RESULTS: Correlations for the 10-year QFFQ with the 24HDRs (average = 0.45) were higher than for the baseline QFFQ (average = 0.41), although the differences were not statistically significant. The increase in correlations was particularly pronounced for Native Hawaiian and African American participants. When absolute values were adjusted for energy intake, the average correlations were higher at 0.57 for the baseline QFFQ and 0.58 for the 10-year QFFQ overall and this pattern was seen in most racial and ethnic subgroups. The average correlations between the two QFFQs were 0.73 for both absolute intakes and nutrient densities overall. CONCLUSIONS: Correlations of nutrient intakes between the two QFFQs and 24HDRs were similar, and intakes from the two QFFQs were highly correlated. QFFQs updated for changes to the food supply may provide improved assessment for cohort studies that include diverse populations.

Body mass index and mortality in an ethnically diverse population: the Multiethnic Cohort Study.

Body mass index (BMI) has been strongly related to overall mortality, but the consistency of this association across diverse ethnic groups and the effects of early adult BMI versus BMI in later adulthood have not been adequately studied. A prospective analysis was performed using data from 183,211 adults aged 45-75 who enrolled the population-based Multiethnic Cohort Study by completing a questionnaire that included self-reported weight and height information in 1993-1996. Participants were African Americans, Native Hawaiians, Japanese Americans, Latinos, and whites living in Hawaii and California. During an average 12.5 years of follow-up, 35,664 deaths were identified. To control for confounding caused by conditions that lead to weight loss and mortality, we excluded participants with a history of cancer or heart disease, who ever smoked, and who died within the first 3 years of follow-up. An increased risk of mortality was observed in participants with a BMI ≥ 27.5 in both men and women compared with the reference category of BMI 23.0-24.9; a BMI ≥ 35.0 carried a greater risk of mortality in men than in women. Although the findings were generally similar across ethnic groups, the association of higher BMI with mortality in Latino men appeared to be weaker than in the other groups. A BMI of 25.0-34.9 at age 21 showed a stronger positive association, with no further increase in risk for a BMI ≥ 35.0, than did BMI in later adulthood. These results indicate that the association of BMI with mortality is generally consistent across sex and ethnic groups, with some variation in the strength of the effect. Most notably, the effect of overweight in young adulthood appears to be much stronger than that of overweight in later adulthood on mortality in later life. This emphasizes the importance of weight management in childhood and adolescence.

Meat and milk intakes and toddler growth: a comparison feeding intervention of animal-source foods in rural Kenya.

OBJECTIVE: To examine the effects of animal-source foods on toddler growth. DESIGN: A 5-month comparison feeding intervention study with one of three millet-based porridges randomized to eighteen feeding stations serving 303 children aged 11-40 months. Feeding stations served plain millet porridge (Plain group), porridge with milk (Milk group) or porridge with beef (Meat group). Anthropometry, morbidity and food intake were measured at baseline and regular intervals. Longitudinal mixed models were used to analyse growth. SETTING: Embu, Kenya. SUBJECTS: Two hundred and seventy-four children were included in final analyses. RESULTS: Linear growth was significantly greater for the Milk group than the Meat group (P = 0·0025). Slope of growth of mid-arm muscle area of the Plain group was significantly greater than in the Meat group (P = 0·0046), while the Milk group's mid-upper arm circumference growth rate was significantly greater than the Meat group's (P = 0·0418). The Milk and Plain groups' measures did not differ. CONCLUSIONS: Milk and meat porridges did not have a significantly greater effect on growth than plain porridge in this undernourished population. Linear growth was influenced by more than energy intakes, as the Plain group's total body weight-adjusted energy intakes were significantly greater than the Meat group's, although linear growth did not differ. Energy intakes may be more important for growth in arm muscle. The diverse age distribution in the study makes interpretation difficult. A longer study period, larger sample size and more focused age group would improve clarity of the results.

Multivitamin use and the risk of mortality and cancer incidence: the multiethnic cohort study.

Although multivitamin/mineral supplements are commonly used in the United States, the efficacy of these supplements in preventing chronic disease or premature death is unclear. To assess the relation of multivitamin use with mortality and cancer, the authors prospectively examined these associations among 182,099 participants enrolled in the Multiethnic Cohort Study between 1993 and 1996 in Hawaii and California. During an average 11 years of follow-up, 28,851 deaths were identified. In Cox proportional hazards models controlling for tobacco use and other potential confounders, no associations were found between multivitamin use and mortality from all causes (for users vs. nonusers: hazard ratio = 1.07, 95% confidence interval: 0.96, 1.19 for men; hazard ratio = 0.96, 95% confidence interval: 0.85, 1.09 for women), cardiovascular diseases, or cancer. The findings did not vary across subgroups by ethnicity, age, body mass index, preexisting illness, single vitamin/mineral supplement use, hormone replacement therapy use, and smoking status. There also was no evidence indicating that multivitamin use was associated with risk of cancer, overall or at major sites, such as lung, colorectum, prostate, and breast. In conclusion, there was no clear decrease or increase in mortality from all causes, cardiovascular disease, or cancer and in morbidity from overall or major cancers among multivitamin supplement users.

Planning Nutritionally Adequate Diets for Groups: Methods Used to Develop Recommendations for a Child and Adult Care Food Program.

Planning nutritionally adequate intakes for large groups of people presents many challenges. Because of between-person variations in both food choices and nutrient requirements, it is necessary to examine nutrient intake distributions and select a Target Median Intake (TMI) that will lead to a low prevalence of inadequate nutrient intakes. The TMI may then be used to guide a feeding or education program. A comprehensive report from the Institute of Medicine evaluated nutrient intakes from the NHANES and recommended new meal patterns for all age groups (other than infants) served by the Child and Adult Day Care Food Program, which provides meals and snacks to children and adults in a variety of care settings. The Estimated Average Requirement, a DRI value, for each nutrient of interest was used to estimate both the prevalence of inadequate intakes as well as the changes in the intake distribution that are needed to reduce unacceptably high levels of inadequacy. For nutrients with an Adequate Intake (AI), the prevalence of inadequacy could not be estimated, but the AI could be used as the TMI. Simultaneously, it was important to ensure that the new intake distributions did not result in intakes that exceeded the Tolerable Upper Intake Level for any nutrient. Data for 2- to 4-y-old children are presented in detail to illustrate this process. Of 18 nutrients examined, analyses showed that intakes of vitamin E, potassium, and fiber should be increased, while intakes of sodium should be decreased. If more recent nutrient standards are used, revised assessments show that calcium intake should also be increased, while potassium intake is adequate. These methods and results should be useful when designing feeding programs for other population groups within the United States, as well as in other countries.

A new simulation model estimates micronutrient levels to include in fortified blended foods used in food aid programs.

Current micronutrient levels in Public Law 480 fortified blended foods (FBF) may not be appropriate for all food aid beneficiaries, particularly infants and/or young children and pregnant and/or lactating women. A simulation model was developed to determine the micronutrient fortification levels to include in FBF for food aid programs with the goal of reducing the risk of inadequate micronutrient intakes without exceeding the tolerable upper intake level (UL) for any recipient group. For each micronutrient, the age and gender group with the highest daily Recommended Nutrient Intake (RNI) relative to energy requirement was identified and the effect of providing different percentages of that RNI (66, 75, and 100%) was simulated. In this modeling exercise, we also examined consumption of the FBF at 25 (the usual level), 50, and 100% of daily energy requirement. Results indicated that 2 FBF products are needed: a complementary food for age 6-36 mo and a supplementary food for the older groups. Both of the FBF could be fortified to supply at least 75% of the RNI to all groups, without exceeding the UL for most nutrients, if consumed at 25% of the energy requirement. Even if consumed at 50% of energy requirements, mean intakes of most micronutrients would not exceed the UL, although at 100% of the energy requirement, several micronutrients were undesirably high. We conclude that fortifying an FBF to provide 75% of the RNI would be appropriate for most micronutrients, but this level of fortification would not be appropriate for long-term consumption of the FBF at 100% of the energy requirements.

Perspective: Proposed Harmonized Nutrient Reference Values for Populations.

Two core nutrient intake reference values (NRVs) are required for assessing the adequacy and safety of nutrient intakes for population groups: the average requirement (AR) and the tolerable upper level of intake (UL). Applications of such assessments include providing advice to improve intakes, formulating complementary foods, estimating the amounts of nutrients to be added to fortified foods and monitoring changes in intake, and product labeling at the global, national, or regional level. However, there is a lack of unity across country-level organizations in the methodological approach used to derive NRVs, and ARs and ULs are lacking in many compilations, thus limiting the ability to assess nutrient intakes for their population groups. Because physiological requirements vary little across populations globally, and setting reference values requires determining an acceptable level of uncertainty, it is feasible to adapt current recommendations from different sources to harmonize these core reference values. The objective of this review is to demonstrate an approach for harmonizing the NRVs for ARs (here termed "H-ARs") and ULs ("H-ULs") that can be applied on a global scale to assessing intakes across populations. The approach incorporates the framework and terminology recommended by reports from the United Nations University, the National Academies of Sciences, Engineering, and Medicine (NASEM), the Institute of Medicine (IOM), and the European Food Safety Authority (EFSA). After reviewing available alternatives, the proposed harmonized values were selected from standards set by EFSA (for Europe) and the IOM (for the United States and Canada), giving priority to those published most recently. Justifications for the proposed values are presented, along with discussion of their limitations. Ideally, these methods should be further reviewed by an international group of experts. Meanwhile, the H-ARs and H-ULs suggested in this review can be used to assess intakes of populations for many applications in global and regional contexts.

Ratios of Food Amounts across Three Portion Size Categories on a Food Frequency Questionnaire in Men and Women.

BACKGROUND: For some quantitative food frequency questionnaire (QFFQ) items, data may be insufficient to set gram weights for multiple portion size (PS) categories. Ratios of food amounts across PS categories may be used to quantify these PS for less frequently consumed food items. OBJECTIVE: To explore the ratios of food amounts reported in 24-hour dietary recalls (24HDRs) by a sample of participants in a cohort study who chose the A (smallest) or C (largest) PS category on the QFFQ, relative to the food amounts for those who chose the B PS category. DESIGN: This study was conducted as a cross-sectional design. PARTICIPANTS/SETTING: Data were from participants (n=2,360) who completed three 24HDRs and the QFFQ in a calibration study of the Multiethnic Cohort Study in 1994-1997. MAIN OUTCOME MEASURES: Median food amounts were calculated from 24HDRs for participants who selected each PS category (A, smallest; B; and C, largest) of items on the QFFQ. A-to-B and C-to-B ratios were computed if reported by five or more people in the 24HDRs: A-to-B ratios for 68 items (men) and 88 items (women); C-to-B ratios for 93 items (men) and 79 items (women). STATISTICAL ANALYSES PERFORMED: The t test was used to compare the mean A-to-B ratios and C-to-B ratios as preset on the QFFQ with those from the 24HDRs and to examine sex differences. Analysis of variance was used to compare the mean ratios among race and ethnicity groups. RESULTS: Mean A-to-B and C-to-B ratios were 0.71±0.15 and 1.45±0.35 in men and 0.71±0.15 and 1.44±0.40 in women based on the 24HDRs. Compared with the original QFFQ PS (A-to-B ratio=0.5±0.07; C-to-B ratio=1.8±0.30), the ratios were closer to 1 both in men and women (P<0.001). There were no significant sex differences or racial or ethnic differences. CONCLUSIONS: These results provide guidance on appropriate ratios to use to set values for small and large PS categories on a QFFQ, particularly for items with insufficient information on usual PS.

Urinary isothiocyanates; glutathione S-transferase M1, T1, and P1 polymorphisms; and risk of colorectal cancer: the Multiethnic Cohort Study.

Although an association between diet, especially cruciferous vegetables, and colorectal cancer has been hypothesized, recent studies have been inconsistent with their findings. One possibility for the discrepant results is that the interaction with related genes has not generally been considered. The present study examined the associations among urinary isothiocyanates, glutathione S-transferase (GST) polymorphisms, and colorectal cancer risk in a case-control study nested within the Multiethnic Cohort Study, based in Hawaii and Los Angeles, California. We measured prediagnositic urinary isothiocyanate levels adjusted for creatinine and analyzed GSTM1, GSTT1, and GSTP1 polymorphisms in 173 cases and 313 matched controls, with biospecimens collected between 2001 and 2006. Conditional logistic regression was used to compute odds ratios and 95% confidence intervals (95% CI). A detectable amount of urinary isothiocyanates was associated with a 41% decrease in colorectal cancer risk (95% CI, 0.36-0.98). No significant, main-effect associations were seen with a homozygous deletion of the GSTM1 or GSTT1 polymorphism, or with the AG or GG genotypes for GSTP1 rs1695. There was a weak suggestion that for individuals with the GSTP1 AG or GG genotype, a detectable amount of isothiocyanates further decreases one's risk of colorectal cancer compared with those with the GSTP1 AA genotype, but the interaction term was not statistically significant (P = 0.09). This is only the second study published on the association between urinary isothiocyanates and colorectal cancer risk. The results suggest that further studies, with larger numbers, examining a possible interaction with the GSTP1 polymorphisms are warranted.

Circulating fatty acids and prostate cancer risk in a nested case-control study: the Multiethnic Cohort.

OBJECTIVE: Dietary fat, including specific fatty acids, has been proposed to contribute to prostate cancer pathogenesis, but findings from the studies based on biomarkers have been conflicting. METHODS: We examined the association between erythrocyte membrane fatty acid composition and prostate cancer risk in a nested case-control study within a multiethnic cohort of African Americans, Native Hawaiians, Japanese Americans, Latinos, and Whites. Analyses included 376 cases and 729 matched controls. Conditional logistic regression was used to estimate the odds ratios and 95% confidence intervals with adjustment for multiple covariates. RESULTS: No significant association was found for saturated, mono- and polyunsaturated fatty acid, or for specific n-3 and n-6 fatty acids, even when the analysis was limited to advanced or high grade prostate cancer. In ethnic specific analyses, there was a positive association with palmitic acid in Japanese Americans that was significantly different from the null results in other groups. There was also an increased risk with n-3 fatty acids and the ratio of n-3/n-6 fatty acids in Whites. CONCLUSION: Although there was a suggestion of ethnic specific associations with some fatty acids, our overall findings do not support a role for fatty acids in prostate carcinogenesis.

The state of the science on dietary sweeteners containing fructose: summary and issues to be resolved.

This article highlights the discussion of the issues that had been raised during the International Life Sciences Institute North America- and USDA Agricultural Research Service-sponsored workshop surrounding the consumption of fructose. One conclusion of the discussion was that the metabolic effects of high-fructose corn syrup (HFCS) and sucrose appear to be similar in humans. However, there have been few studies directly comparing the effects of fructose to other caloric sweeteners, such as glucose, HFCS, and sucrose. Differential effects may include those related to insulin sensitivity, triglyceride and lipoprotein levels, and glycated protein levels. Further exploration of the differences between nutritive sweeteners should be the basis of a research agenda. Studies should also further investigate factors that might affect the results, such as the amount and form of the sweetener consumed, the macronutrient composition of the basal diet, the length of the study, and the characteristics of the subjects. Meanwhile, health professionals could help consumers by providing simple messages, such as the importance of consuming lower levels of energy, including those from all caloric sweeteners.

Dietary micronutrients are associated with higher cognitive function gains among primary school children in rural Kenya.

With the exception of iodine and Fe, there is still very limited information on the effect of micronutrients on cognitive function, especially among school-age children. The present analysis evaluates the relationship between dietary Fe, Zn and B vitamins (B12, B6, folate and riboflavin) and gains in cognitive test scores among school children in rural Kenya. Data for the present study were obtained from The Child Nutrition Kenya Project, a 2-year longitudinal, randomised controlled feeding intervention study using animal source foods. Dietary nutrient values were based on monthly and bimonthly 24 h recall data collected during the study period. In longitudinal regression analyses, available Fe, available Zn, vitamin B12 and riboflavin showed significant relationships with improved cognitive test scores, after controlling for confounders such as energy intake, school, socio-economic status and morbidity. Available Fe intake was associated with significantly higher gains in Raven's Coloured Progressive Matrices test scores over time. Available Zn intake was associated with significantly higher gains in digit span-total test scores over time, while vitamin B12 and riboflavin intakes were each associated with significantly higher gains in digit span-forward test scores over time. This analysis demonstrates the influence of improved dietary micronutrient status on school children's cognitive function.

Carotenoid intake and colorectal cancer risk: the multiethnic cohort study.

BACKGROUND: A protective effect of fruits and vegetables against colorectal cancer has been supported by many epidemiologic studies. This suggests that the carotenoids frequently found in these foods play a role in the prevention of this common cancer. To examine associations between the intake of individual and total carotenoids and the risk of colorectal cancer, we analyzed prospective data from the Multiethnic Cohort Study. METHODS: This analysis includes 85 898 men and 105 106 women who completed a quantitative food frequency questionnaire in 1993-1996. The participants were African Americans, Native Hawaiians, Japanese Americans, Latinos, and whites aged 45-75 years at cohort entry. After an average follow-up of 8.2 years, 1292 and 1086 incident cases of colorectal cancer were identified in men and women, respectively. Cox proportional hazard models were used to estimate relative risks of colorectal cancer. RESULTS: No significant associations were found between intake of individual and total carotenoids and colorectal cancer risk either in men or women, except for beta-cryptoxanthin, which showed a mild protective effect in men. When the associations were investigated separately for colon and rectal cancer, lycopene intake was related to an increased risk of rectal cancer in men. A decreased risk was seen for total beta-carotene in male current smokers, but the test for interaction with smoking status was not significant. No association was observed in each ethnic-sex group. CONCLUSION: Overall, our findings do not support a significant association between carotenoid intake and colorectal cancer, although some associations were seen in subgroup analyses.