Retinol Intake Research Articles

A population-based case-control study of carotenoid and vitamin A intake and ovarian cancer (United States).

To evaluate the association between dietary intake of carotenoids and vitamin A and the incidence of ovarian cancer. We conducted a population-based case-control study of ovarian cancer in Massachusetts and Wisconsin. Incident cases diagnosed between 1991 and 1994 were identified through statewide tumor registries. We selected community controls at random from lists of licensed drivers and Medicare recipients; 327 cases and 3129 controls were included in the analysis. Data were collected by telephone interview, which included an abbreviated food and supplement list to quantify typical consumption of carotenoids (lutein/zeaxanthin, alpha-carotene, beta-carotene), retinol and total vitamin A at 5 years prior to diagnosis in cases, or to a comparable reference date in controls. Results were adjusted for age, state, and other risk factors. Participants with the highest dietary intake of lutein/zeaxanthin (> or =24,000 microg/week) experienced a 40% lower risk of ovarian cancer (95% CI = 0.36-0.99) compared to those with the lowest intake. Intake of alpha-carotene, beta-carotene, retinol and total vitamin A was unrelated to risk. Among foods, we observed non-significantly lower risks with high consumption of spinach, carrots, skim/lowfat milk and liver. These results support previous findings suggesting an inverse relationship between carotenoid intake and ovarian cancer risk.

Dietary antioxidant vitamins, retinol, and breast cancer incidence in a cohort of Swedish women.

Dietary antioxidant vitamins and retinol have been proposed to be protective against breast cancer on the basis of their ability to reduce oxidative DNA damage and their role in cell differentiation. Epidemiologic studies have not been convincing in supporting this hypothesis, but women with high exposure to free radicals and oxidative processes have not been specifically considered. We explored these issues in the Swedish Mammography Screening Cohort, a large population-based prospective cohort study in Sweden that comprised 59,036 women, 40-76 years of age, who were free of cancer at baseline and who had answered a validated 67-item food frequency questionnaire. During 508,267 person-years of follow-up, 1,271 cases of invasive breast cancer were diagnosed. Cox proportional hazards models were used to obtain hazard ratios (HRs) and 95% confidence intervals (CIs). There was no overall association between intake of ascorbic acid, beta-carotene, retinol or vitamin E and breast cancer incidence. High intake of ascorbic acid was inversely related to breast cancer incidence among overweight women (HR=0.61; 95% CI 0.45-0.82, for highest quintile of intake among women with body mass index>25 kg/m(2)) and women with high consumption of linoleic acid (HR=0.72; 95% CI 0.52-1.02, for highest quintile of ascorbic acid intake and average consumption of more than 6 grams of linoleic acid per day). Among women with a body mass index of 25 or below, the hazard ratio for breast cancer incidence was 1.27 (95% CI 0.99-1.63), comparing the highest to the lowest quintile of ascorbic acid intake. Consumption of foods high in ascorbic acid may convey protection from breast cancer among women who are overweight and/or have a high intake of linoleic acid.

The Anti Cancer Council of Victoria FFQ: relative validity of nutrient intakes compared with weighed food records in young to middle‐aged women in a study of iron supplementation

ObjectiveTo assess the validity of the Anti Cancer Council of Victoria food frequency questionnaire (ACCVFFQ) relative to seven‐day weighed food records (WFRs) in 63 women of child‐bearing age. Method63 women completed WFRs to assess iron intake as part of a study on iron deficiency. These women also completed the ACCVFFQ. Nutrient intakes were computed independently for the WFRs and FFQs. Intakes were compared as group means, by correlation and by quintile classification, adjusting for day‐to‐day variation in intakes, and for energy intake. Individual differences in results were also examined. ResultsThe strongest associations between WFR and FFQ results were energy‐adjusted, log‐transformed and adjusted for day‐to‐day variability in intake. Correlation coefficients ranged from 0.28 for vitamin A to 0.78 for carbohydrate. Mean intakes from the WFRs and FFQs were within +/‐20% for 21 of 27 nutrients. Poor agreement between FFQs and WFRs for retinol intake was due to the inclusion of liver in two WFRs, an item which is not included in the FFQ. ConclusionThe ACCVFFQ performs as well as other FFQs for which validation data are available. The relatively poor measurement of retinol is consistent with other data, and with the limited number of foods in which this nutrient is abundant. ImplicationsThe availability of an optically scannable valid instrument for assessing dietary intake will facilitate epidemiological studies of diet and disease, an area of current research priority.

Foods and Nutrients in Relation to Bladder Cancer Risk: A Case-Control Study in Aichi Prefecture, Central Japan

To elucidate the role of diet in the etiology of bladder cancer, we conducted a case-control study from 1996 to 1999 in Aichi Prefecture, Central Japan. Cases were patients newly diagnosed with bladder cancer, and one hospital control was selected for each case, matching gender, age, and hospital. A well-validated food frequency questionnaire was adopted to estimate intakes of nutrients and food groups. Odds ratios (ORs) adjusted for smoking and occupational history were computed using conditional logistic models. The analyses based on 297 cases and 295 controls revealed the following. 1) The more the intake of milk and dairy products, the lower the OR; the ORs across quartiles in all subjects were 1.02, 0.73, and 0.52. Fruit intake was negatively associated with the risk, particularly in men (ORs across quartiles = 0.76, 0.77, and 0.52). Green-yellow vegetables were associated with a decreased risk in the highest quartile of consumption in men (OR = 0.57). 2) Dietary intakes of retinol and saturated fatty acids were related to a reduced risk in all subjects (ORs across quartiles = 0.75, 0.54, and 0.66 and 0.55, 0.54, and 0.60, respectively). Monounsaturated fatty acids had an inverse association with bladder cancer risk in men.

High Levels of Retinol Intake During the First Trimester of Pregnancy Result from Use of Over-the-counter Vitamin/Mineral Supplements

High Levels of Retinol Intake During the First Trimester of Pregnancy Result from Use of Over-the-counter Vitamin/Mineral Supplements

Lifestyle and Anthropometric Risk Factors for Prostate Cancer in a Cohort of Iowa Men

PURPOSE: Several lines of evidence suggest that prostate cancer has a hormonal etiology. We evaluated factors known to modulate the endocrine system, including alcohol and tobacco use, physical activity, and obesity as risk factors for prostate cancer. METHODS: Cancer-free controls n = 1572 who participated in a population-based case-control study from 1986–1989 (81% response rate) were followed through 1995 for cancer incidence by linkage to the Iowa Cancer Registry; 101 incident prostate cancers were identified. RESULTS: Compared with non-users of alcohol, men who consumed <22 grams alcohol per week (relative risk [RR] = 1.1; 95% Confidence Interval [CI] 0.6–2.1), 22–96 grams alcohol per week (RR = 2.6; 95% CI 1.4–4.6) and >96 grams alcohol per week (RR = 3.1; 95% CI 1.5–6.3) were at increased risk of prostate cancer after adjustment for age, family history of prostate cancer, body mass index, total energy, and intake of carbohydrate, linoleic acid, lycopene, retinol, and red meat ( p for trend < 0.0001). The respective RRs were similar when assessing type of alcohol consumed (beer, wine or liquor) or when well-differentiated, localized tumors were excluded. Body mass index was only weakly and positively associated with prostate cancer after adjustment for age p for trend = 0.3 , but this association strengthened after multivariate adjustment p for trend = 0.08 and exclusion of well-differentiated, localized tumors p for trend = 0.03 . For the latter tumors, men with a BMI of 24.1–26.6 kg/ m 2 RR = 1.5; 95% CI 0.7 – 3.0 and >26.6 kg/ m 2 RR = 2.1; 95% CI 1.1–4.3 were at elevated risk compared to men with a BMI <24.1 kg/m 2. Tobacco use (cigarettes, cigar/pipe, chewing tobacco and snuff use), height, weight, and both leisure and occupational physical activity were not associated with risk of prostate cancer in this cohort. CONCLUSIONS: These data suggest that in white men obesity is a risk factor for more clinically significant prostate cancer and confirm limited previous reports showing that alcohol consumption is positively associated with prostate cancer and that this risk is not limited to any specific type of alcohol.

Implications of diet and nutrition for growth and prevalence of anaemia in rural preschool‐aged children in Shandong Province, China

A nutrition surveillance and nutritional improvement programme through nutrition field worker training, nutrition education and encouraging the utilization of home gardens was undertaken among rural preschoolaged children in the four counties of Linshu, Caoxin, Zoucheng and Yucheng in Shandong Province in China from 1990 to 1995. A baseline survey was conducted in 1990. This included physical and biochemical measurements being taken on 3474 children aged 0-5 years and dietary household surveys being taken on a random subsample of 312 children. The baseline survey showed that the average height and weight of the subjects was lower than the World Health Organization (WHO) standard with the prevalence of stunting, underweight and wasting being 24.2, 12.5 and 2.1%, respectively (using the Z scores <= -2 as the cut-off point). The prevalence of anaemia was 61.9% (using haemoglobin (HB) <= 110 g/L as the cut-off point). The range of mean intakes of protein and energy was, respectively, 54.0-67.2% and 56.4-68.4% of the Chinese recommended dietary allowance (RDA) depending on the age group. Mean calcium intake was less than 30% of the RDA for all age groups and the mean intakes of ascorbic acid, niacin, retinol and riboflavin were between 30.6 and 96.1% of the RDA. Nutrition education and nutrition field worker training were the key components of the intervention phase that followed the baseline survey. Over 5 years, 531 nutrition field workers were trained, 1200 parents joined in nutrition classes and approximately 8000 villagers received basic nutrition information. The latter included promotion of breast-feeding, identification of sources of appropriate foods for weaning, and also for the prevention and treatment of common nutritional deficiencies. Home gardens for fruit, vegetable and livestock were also encouraged. The evaluation survey of the project was conducted in 1995 among 2728 0-5- year-old children. The results indicated that the nutritional status of preschool-aged children had improved greatly. The prevalence of stunting and underweight was reduced by 37.8 and 21.3%, respectively, while there was no significant change in the prevalence of wasting. The average rate of anaemia decreased by 79.6% in 1995.

Vitamins, carotenoids, dietary fiber, and the risk of gastric carcinoma

BACKGROUND Numerous components of fruit and vegetables are considered to decrease the risk of gastric carcinoma. In the current prospective study, the authors examined the association between the intake of vitamins, carotenoids, and dietary fiber and vitamin supplement use and the incidence rate of gastric carcinoma. METHODS The Netherlands Cohort Study began in 1986 with 120,852 men and women ages 55–69 years. Data regarding diet and other covariates were collected by means of a self-administered questionnaire. After 6.3 years of follow-up, data regarding 282 incident cases of gastric carcinoma and 3123 subcohort members were available for case-cohort analyses. RESULTS In analyses adjusted for age, gender, smoking history, education, stomach disorders, and family history of gastric carcinoma, an inverse association with vitamin C intake (relative risk [RR] for highest vs. lowest intake category, 0.7; 95% confidence interval [95% CI], 0.5–1.0) was observed, with a borderline significant trend across three intake categories (P = 0.06). After the exclusion of cases diagnosed in the first and second follow-up years, the RR was 0.9 (95% CI, 0.6–1.2; P trend = 0.44). Intake of retinol and β-carotene were associated positively with gastric carcinoma risk with highest versus lowest quintile RRs of 1.6 (95% CI, 1.0–2.5; P trend = 0.02) and 1.6 (95% CI, 1.0–2.6; P trend = 0.13), respectively, after the exclusion of first-year and second-year cases. Intake of folate, vitamin E, α-carotene, lutein plus zeaxanthin, β-cryptoxanthin, lycopene, and dietary fiber was not associated with gastric carcinoma. Patients who used vitamin A-containing supplements had a lower risk of gastric carcinoma than nonusers (RR = 0.4; 95% CI, 0.2–0.9). CONCLUSIONS No clear inverse associations were found between the intake of vitamins, carotenoids, and dietary fiber and the risk of gastric carcinoma after adjustment for confounding variables and the exclusion of first-year and second-year cases. Cancer 2000;88:737–48. © 2000 American Cancer Society.

Vitamins, carotenoids, dietary fiber, and the risk of gastric carcinoma

Numerous components of fruit and vegetables are considered to decrease the risk of gastric carcinoma. In the current prospective study, the authors examined the association between the intake of vitamins, carotenoids, and dietary fiber and vitamin supplement use and the incidence rate of gastric carcinoma. The Netherlands Cohort Study began in 1986 with 120,852 men and women ages 55-69 years. Data regarding diet and other covariates were collected by means of a self-administered questionnaire. After 6.3 years of follow-up, data regarding 282 incident cases of gastric carcinoma and 3123 subcohort members were available for case-cohort analyses. In analyses adjusted for age, gender, smoking history, education, stomach disorders, and family history of gastric carcinoma, an inverse association with vitamin C intake (relative risk [RR] for highest vs. lowest intake category, 0.7; 95% confidence interval [95% CI], 0.5-1.0) was observed, with a borderline significant trend across three intake categories (P = 0. 06). After the exclusion of cases diagnosed in the first and second follow-up years, the RR was 0.9 (95% CI, 0.6-1.2; P trend = 0.44). Intake of retinol and beta-carotene were associated positively with gastric carcinoma risk with highest versus lowest quintile RRs of 1. 6 (95% CI, 1.0-2.5; P trend = 0.02) and 1.6 (95% CI, 1.0-2.6; P trend = 0.13), respectively, after the exclusion of first-year and second-year cases. Intake of folate, vitamin E, alpha-carotene, lutein plus zeaxanthin, beta-cryptoxanthin, lycopene, and dietary fiber was not associated with gastric carcinoma. Patients who used vitamin A-containing supplements had a lower risk of gastric carcinoma than nonusers (RR = 0.4; 95% CI, 0.2-0.9). No clear inverse associations were found between the intake of vitamins, carotenoids, and dietary fiber and the risk of gastric carcinoma after adjustment for confounding variables and the exclusion of first-year and second-year cases.

Toenail selenium and breast cancer-a case-control study in Finland.

Low levels of selenium have been associated with a higher risk of cardiovascular diseases and cancer in humans. Since 1984, selenium supplementation through fertilizers has been employed in Finland to increase the very low concentration of selenium in the nation's food supply. As a result, the selenium concentration of Finnish foods became one of the highest in Europe. A decade after selenium supplementation began, the association between toenail selenium and the risk of breast cancer was examined. Case-control study. Eastern Finland. 289 pre- and postmenopausal breast cancer cases and 433 community controls. The diagnosis was unknown at the time the toenail samples were collected. The mean toenail selenium concentration was 0.80 mg/kg in premenopausal cases and 0.84 mg/kg in premenopausal controls: and 0. 77 mg/kg in postmenopausal cases and 0.80 mg/kg in postmenopausal controls. The odds ratio (OR) comparing the highest with the lowest quintiles of toenail selenium concentration was 1.1 (95% CI 0.4-3.2) in premenopausal women and 0.7 (95% CI 0.3-1.5) in postmenopausal women. The intake of retinol, beta-carotene, vitamin E and vitamin C did not change the association between toenail selenium and breast cancer. A decade after selenium supplementation, selenium seems not to be an important factor in the etiology of breast cancer, neither in premenopausal nor postmenopausal women. This work was supported by the EVO funds from the Kuopio University Hospital and by research grants from the Academy of Finland, Yrjö Jahnsson Foundation and Juho Vainio Foundation. European Journal of Clinical Nutrition (2000) 54, 98-103

Diet and basal cell carcinoma of the skin in a prospective cohort of men

Low intake of fat and high intake of specific vitamins have been hypothesized to reduce risk of basal cell carcinoma of the skin (BCC). Our objective was to examine intakes of fat, antioxidant nutrients, retinol, folate, and vitamin D in relation to risk of BCC. In 1986, diet was assessed by a validated food-frequency questionnaire in 43217 male participants of the Health Professionals Follow-up Study who were 40-75 y of age and free of cancer. During 8 y of follow-up, we ascertained 3190 newly diagnosed cases of BCC. Total fat consumption was associated with a lower risk of BCC [relative risk (RR): 0.81; 95% CI: 0.72, 0.90 for the highest compared with the lowest quintile of intake; P for trend < 0.001). Simultaneous modeling of specific fatty acids suggested that this inverse association was limited to monounsaturated fat (RR: 0.79; 95% CI: 0.65, 0.96; P for trend = 0. 02); saturated and polyunsaturated fat were not associated with BCC risk. Folate intake was associated with a slightly higher risk of BCC (RR: 1.19; 95% CI: 1.01, 1.40; P for trend = 0.11), whereas alpha-carotene was associated with a slightly lower risk (RR: 0.88; 95% CI: 0.79, 0.99; P for trend = 0.01). Intakes of long-chain n-3 fatty acids, retinol, vitamin C, vitamin D, or vitamin E were not materially related to BCC risk. These findings do not support the hypothesis that diets low in fat or high in specific vitamins lower risk of BCC.

Dietary Vitamin A Intakes of Preschool-Age Children in South India

The vitamin A intake of children aged 1–3 y (n = 683) was assessed using a quantitative food-frequency questionnaire in a vitamin A intervention study in South India. Trained field workers interviewed mothers about their children’s usual consumption of common sources of vitamin A and collected information on portion sizes using standard cups. Mothers were asked to state the number of months in a year during which specific seasonal foods were available. Information about current breast-feeding was also obtained. Vitamin A intakes from nonbreast milk sources were extremely low at all ages. The median intake of total vitamin A, β-carotene and retinol was 121, 100 and 21 retinol equivalents (RE), respectively. Maternal education and socioeconomic status (SES) were positively associated with total vitamin A and retinol intakes. Girls had significantly lower intakes than boys even after adjusting for differences in age, maternal education, SES and breast-feeding status. Breast-feeding was common, but declined to 60% by 24 mo and to 15% by 36 mo. Vitamin A intakes from nonbreast milk sources increased with age only for currently breast-fed children, who tended to be of lower SES. After taking into account the potential contribution of breast milk by using published estimates, nonbreast-fed children met only 60% of the Indian recommended dietary allowance (RDA; 250 RE/d), whereas breast-fed children met ∼90% of the RDA during y 2 of life.

Plasma vitamin A, E, and beta-carotene levels in adult post-partum Algerian women.

Vitamins A and E are essential for foetal growth, reproduction, and lactation. In this article we report the results of a study, lead in three Eastern Algeria cities, that involved 786 post-partum women and 250 control. Plasma levels of vitamins A, E, beta-carotene, and some nutritional indexes were measured in both groups. In control women, plasma retinol and beta-carotene levels were significantly lower in Algeria than in France (retinol: 1.4 +/- 0.42 vs. 1.78 +/- 0.53 mumol/l; beta-carotene: 0.35 +/- 0.261 vs. 0.94 +/- 0.611). These differences could be the consequence of different beta-carotene and retinol intakes. In Algeria, comparisons between post-partum women and controls, showed that plasma vitamin A and beta-carotene levels were significantly lower in post-partum than in control women. This fact, and the lower level of retinol in control women, raises the question of supplementation for pregnant women in Algeria, at least for those with the lowest standard of living whose protein and zinc levels are also very low after delivery. Plasma vitamin E levels and vitamin E/total lipid ratios were not different in Algeria and in France. Vitamin E concentration was higher during pregnancy, but the vitamin E/total lipid ratio was significantly lower, which shows a relative deficiency at the end of pregnancy. Comparisons of plasma vitamin E levels, at delivery, in primiparous and in multiparous women reveal a better tocopherol status in multiparous women. This difference could reflect an adaptive response to oxidative stress in multiparous women.

Questionnaire Assessment of Antioxidants and Retinol Intakes in Mexican Women

Background In order to assess intake of antioxidants and retinol, we evaluated the validity and reproducibility of a semiquantitative food frequency questionnaire. Methods Data were collected from 110 women, aged 15–54 years, who resided in the southern part of Mexico City. Study participants were asked to complete the food frequency questionnaire before and after completing four series of 4 days of 24-h diet recalls. We obtained the 24-h recalls at 3-month intervals designed to account for seasonal variability. In addition, we measured serum blood levels of retinol and various carotenoids at 3 and 9 months after baseline. Results Intraclass correlation coefficients for intake of energy-adjusted daily nutrients, assessed by the questionnaires 1 year apart, ranged from 0.23 for lutein/zeaxanthin to 0.50 for total carotenes. Correlation coefficients between energy-adjusted nutrient intakes were measured by means of the sixteen 24-h dietary recalls, and the second questionnaire ranged from 0.09 for lutein/zeaxanthin to 0.45 for total carotenes. These correlations were higher after adjusting for day-to-day variations in diets ranging from 0.11 for lutein/zeaxanthin to 0.49 for vitamin C. Correlation coefficients between intake and biochemical measures were 0.32 for alpha-carotene, 0.34 for beta-carotene, and 0.40 for total carotene after adjusting for age, body mass index, cholesterol and triglyceride plasma levels, smoking status, and caloric intake. Conclusions These data support the ability of our food frequency questionnaire to provide valid information on the relative intake of these nutrients and to confirm its usefulness in epidemiological studies of diet-disease relations. However, its application outside Mexico City or in different age or gender populations will require additional modifications and validation efforts.

Effects of long-term intake of retinol on selected clinical and laboratory indexes

Chemopreventive agents developed to be used in a moderate-risk but otherwise healthy population need to be both efficacious and to have minimal adverse effects. The objective of this study was to evaluate the adverse effects of long-term retinol intake in a skin cancer chemoprevention trial in a large population at moderate risk for skin cancer. Participants (n = 2297) were randomly assigned to receive retinol [7576 retinol equivalents (RE), or 25000 IU] or a placebo daily. The adverse effects of retinol intake were studied by monitoring 14 clinical symptoms and laboratory indexes. The median follow-up time was 3.8 y. No adverse effects concerning the 14 symptoms were observed. Significant differences in alkaline phosphatase (P < 0.0001), triacylglycerol (P < 0.0001), cholesterol (P = 0.04), and HDL (P = 0.01) were observed over time between the 2 groups. After 49 mo of follow-up, alkaline phosphatase was 7% higher, triacylglycerol was 11% higher, cholesterol was 3% higher, and HDL was 1% lower in the retinol group than in the placebo group. Because a 1% increase in cholesterol concentrations has been reported to be associated with a 2% increase in coronary artery disease risk, long-term ingestion of 7576 RE vitamin A/d should be considered with caution. However, further studies are needed to confirm this finding.

Dietary antioxidants and age-related maculopathy: The blue mountains eye study

Objective To assess associations between the stages of age-related maculopathy (ARM) and dietary intake of carotene, vitamin C, retinol, and zinc. Design Cross-sectional, population-based study. Participants A total of 3654 subjects 49 years of age and older from a defined area, west of Sydney, Australia, participated. A total of 2900 participants (79.4%) completed accurate food records. Intervention Masked grading of stereoscopic macular photographs, detailed interviewer-administered questionnaire, and 145-item self-administered food frequency questionnaire. Main outcome measures Late ARM and early ARM were diagnosed from photographic grading. Results The authors found no statistically significant associations between ARM and dietary intake of either carotene, zinc, or vitamins A or C, either from diet or supplements or from the combined intake from diet and supplements. Multivariate-adjusted odds ratios (95% confidence interval) were calculated comparing highest to lowest dietary intake quintiles. For late ARM, the odds ratios were carotene, 0.7 (range, 0.3–2.0); vitamin A, 1.2 (range, 0.5–3.3); vitamin C, 1.3 (range, 0.5–3.4); and zinc, 1.0 (range, 0.4–2.8). For early ARM, the odds ratios were carotene, 0.7 (range, 0.4–1.1); vitamin A, 1.2 (range, 0.7–2.0); vitamin C, 0.9 (range, 0.5–1.4); and zinc, 0.8 (range, 0.5–1.3). No significant trends were apparent. Adjustment for energy intake also showed no associations between these antioxidants and ARM. Further, no associations were found between increasing intake of foods high in antioxidant vitamins and decreasing prevalence of either late or early ARM. Conclusions The authors found no associations between ARM and dietary antioxidants, either from diet alone or including supplements, or from selected foods, in the Blue Mountains Eye Study population.

Fat-soluble nutrient concentrations in different layers of human cataractous lens

PURPOSE. Recent epidemiologic studies suggest that differential risk for cataract in different areas of the lens may be related to intake of carotenoids, retinol, and tocopherol. Nevertheless, there is little information about differential localization of these nutrients in the lens. To determine the spatial distribution of fat-soluble nutrients within the lens, we determined levels of these nutrients in the epithelium/ outer cortex vs. inner cortex/nucleus. METHODS. Concentrations of carotenoids, retinol, and tocopherol were determined in the epithelial/cortical (younger, more metabolically active tissue) and nuclear (older, less metabolically active) layers of human cataractous lenses (n = 7, 64–75 yr) by reverse-phase high-performance liquid chromatography (HPLC). RESULTS. Lutein/zeaxanthin was the only carotenoid, which was detected, in human lens. Consistent with prior reports, no ß-carotene or lycopene were detected. Concentrations of lutein/zeaxanthin, tocopherol, and retinol in epithelium/cortex tissue were approximately 3-, 1.8-, and 1.3-fold higher than in the older lens tissue. Specifically, the epithelial/cortical lens layer, comprising about half of the tissue, contains 74% of lutein/zeaxanthin (44 ng/g wet wt), 65% of a-tocopherol (2227 ng/g wet wt), and 60% of retinol (30 ng/g wet wt). CONCLUSIONS. The data suggest that upon development and aging, there is differential localization of these nutrients. The data are also consistent with a protective role of these nutrients against oxidative damage in the epithelium and cortex of the human lens.

Vitamins A, C and E and the risk of breast cancer: results from a case-control study in Greece.

Although several dietary compounds are hypothesized to have anticarcinogenic properties, the role ofpecific micronutrients in the development of breast cancer remains unclear. To address this issue, we assessed intake of retinol, β-carotene, vitamin C and vitamin E in relation to breast cancer risk in a case–control study in Greece. Eight hundrednd twenty women with histologically confirmed breast cancer were compared with 1548 control women. Dietary data were collectedhrough a 115-item semiquantitative food frequency questionnaire. Data were modelled by logistic regression, with adjustment forotal energy intake and established breast cancer risk factors, as well as mutual adjustment among the micronutrients. Amongost-menopausal women, there was no association between any of the micronutrients evaluated and risk of breast cancer. Amongremenopausal women, β-carotene, vitamin C and vitamin E were each inversely associated with breast cancer risk, but afterutual adjustment among the three nutrients only β-carotene remained significant; the odds ratio (OR) for a one-quintilencrease in β-carotene intake was 0.84 (95% confidence interval 0.73–0.97). The inverse association observed with β-carotene intake, however, is slightly weaker than the association previously observed with vegetable intake in these data,aising the possibility that the observed β-carotene effect is accounted for by another component of vegetables. ©1999 Cancer Research Campaign

Excessive dietary intake of vitamin A is associated with reduced bone mineral density and increased risk for hip fracture.

The highest incidence of osteoporotic fractures is found in northern Europe, where dietary intake of vitamin A (retinol) is unusually high. In animals, the most common adverse effect of toxic doses of retinol is spontaneous fracture. To investigate whether excessive dietary intake of vitamin A is associated with decreased bone mineral density and increased risk for hip fracture. A cross-sectional study and a nested case-control study. Two counties in central Sweden. For the cross-sectional study, 175 women 28 to 74 years of age were randomly selected. For the nested case-control study, 247 women who had a first hip fracture within 2 to 64 months after enrollment and 873 age-matched controls were selected from a mammography study cohort of 66,651 women 40 to 76 years of age. Retinol intake was estimated from dietary records and a food-frequency questionnaire. Bone mineral density was measured with dual-energy x-ray absorptiometry. Hip fracture was identified by using hospital discharge records and was confirmed by record review. In multivariate analysis, retinol intake was negatively associated with bone mineral density. For every 1-mg increase in daily intake of retinol, risk for hip fracture increased by 68% (95% CI, 18% to 140%; P for trend, 0.006). For intake greater than 1.5 mg/d compared with intake less than 0.5 mg/d, bone mineral density was reduced by 10% at the femoral neck (P = 0.05), 14% at the lumbar spine (P = 0.001), and 6% for the total body (P = 0.009) and risk for hip fracture was doubled (odds ratio, 2.1 [CI, 1.1 to 4.0]). High dietary intake of retinol seems to be associated with osteoporosis.

Intake of very-long-chain n-3 fatty acids related to social status and lifestyle.

Little information is available about the intake of very-long-chain n-3 fatty acids in random samples of populations. We examined if the intake of these fatty acids was associated with gender, social status and lifestyle in a similar way as other indicators for a healthy diet in a nationwide survey. Data were obtained from self-administered quantitative food frequency questionnaires filled in by a representative sample of Norwegian men and women, aged 16-79 y. 3144 (63%) of the invited subjects responded with acceptable questionnaires. Daily intake of very-long-chain n-3 fatty acids was on average 0.9 g/d and 0.4% of total energy was derived from these fatty acids. Energy derived from very-long-chain n-3 fatty acids was slightly higher among men than women, and two-fold higher among subjects aged 60-79 vs 16-29 y. White collar workers had higher intake of very-long-chain n-3 fatty acids than blue collar workers. Men and women in the highest quartile of intake of very-long-chain n-3 fatty acids had 2-3 E% higher fat intake (mostly mono- and polyunsaturated fatty acids), as compared to individuals in the lowest quartile. They also had 3-4 fold higher daily intake of retinol and vitamin D, as well as 20-50% higher intake of fruits and vegetables, dietary fibre and vitamin C. Intake of very-long-chain n-3 fatty acids was correlated to indicators for healthy dietary habits. However, contrary to many other indicators of a healthy diet, energy derived from very-long-chain n-3 fatty acids was not significantly associated with female gender or non-smoking.