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At least 19 recordsLinked to original sources
PubMed1999

Effect of daily and weekly micronutrient supplementation on micronutrient deficiencies and growth in young Vietnamese children.

BACKGROUND: Micronutrient deficiencies remain common in preschool children in developing countries. Interventions focus on single micronutrients and often lack effectiveness. Weekly instead of daily supplementation may improve effectiveness. OBJECTIVE: The efficacy of weekly and daily supplementation in reducing anemia prevalence and in improving the zinc, vitamin A, and growth status of 6-24-mo-old Vietnamese children was investigated. DESIGN: In this double-blind, placebo-controlled trial, the daily group (n = 55) received 8 mg elemental Fe (as iron sulfate), 5 mg elemental Zn (as zinc sulfate), 333 microg retinol, and 20 mg vitamin C 5 d/wk for 3 mo. The weekly group (n = 54) received 20 mg Fe, 17 mg Zn, 1700 microg retinol, and 20 mg vitamin C once a week. A third group (n = 54) received a placebo only. Venous blood samples were collected at the start and end of the supplementation period and anthropometric measurements were taken at the start and 3 mo after the end of supplementation. RESULTS: At baseline, 45.6% of subjects had hemoglobin concentrations < 110 g/L, 36.3% had zinc concentrations < 10.71 micromol/L, and 45.6% had retinol concentrations <0.70 micromol/L. Hemoglobin, retinol, and zinc concentrations of both the weekly and daily groups increased similarly compared with the placebo group (P < 0.001). There was no significant difference in growth between the supplemented groups and the placebo group. However, the height-for-age of subjects stunted at baseline increased with z scores of 0.48 (P < 0.001) and 0.37 (P < 0.001) for the daily and weekly groups, respectively. CONCLUSIONS: Weekly and daily supplementation improved hemoglobin, zinc, and retinol concentrations similarly. Neither intervention affected growth of the overall population, but growth of children stunted at baseline was improved through both types of supplementation.

Ascorbic Acid Deficiency↗
PubMed1993

Comparison of micronutrient intake measured by a dietary questionnaire and biochemical indicators of micronutrient status.

We compared the intake of 12 micronutrients as reported on a semiquantitative food frequency questionnaire with corresponding biochemical indicators of nutrient status in a sample of 57 males and 82 females aged 40-83 y. Age-, sex-and energy-adjusted correlation coefficients ranged from near zero for thiamin, vitamin A, and zinc to 0.63 for folate. Correlation coefficients between intake and the biochemical measures were > 0.30 for carotenoids, vitamin D, vitamin E, vitamin B-12, folate, and vitamin C. Differences of 50% or more were observed between extreme quartiles of intake for mean plasma concentrations of folate, vitamin B-12, and vitamin C. Excluding nutrient supplement users generally reduced the correlations. These data demonstrate that food frequency questionnaires can provide valid information on intake for a number of micronutrients.

Adult↗
PubMed1993

Serum beta-carotene and antioxidant micronutrients in children with cancer. The 'Cancer in Children and Antioxidant Micronutrients' French Study Group.

Serum antioxidant vitamins A (retinol) and E (alpha-tocopherol), beta-carotene, zinc and selenium for 418 children with newly diagnosed malignancy were compared with those of 632 cancer-free controls. Incident cancer cases and controls were 1-16 years old and recruited in 1986-1989. Age- and sex-adjusted serum concentrations of retinol, beta-carotene and alpha-tocopherol were significantly inversely associated with cancer. In similar models, the odds ratio (OR) comparing the highest with the lowest quintile was 2.06 (95% confidence interval [CI] 1.40-3.02) for retinol, 3.87 (95% CI: 2.54-5.90) for beta-carotene, 2.15 (95% CI: 1.48-3.10) for alpha-tocopherol, 1.29 (95% CI: 0.75-2.23) for selenium, and 1.94 (95% CI: 1.17-2.23) for zinc. The cancer sites that were associated with serum beta-carotene were, in general, leukaemia, lymphoma, central nervous system, bone and renal tumours. Moreover, leukaemia was associated with low mean serum levels of retinol, selenium and zinc. Subjects with lymphoma, bone and renal tumours also had lower mean retinol and alpha-tocopherol levels than controls. Brain tumour patients had low vitamin E levels. Low serum values of antioxidant vitamins were associated with childhood neoplasm occurrence. Some site-specific effect was reported. Low peripheral nutrient levels are not considered as cancer promoters but rather as an impairment of the body's defence mechanism occurring during the cancer-related metabolic and nutritional disturbances and inflammation processes.

Adjuvants, Immunologic↗
PubMed1998

Effects of micronutrients on metal toxicity.

There is growing evidence that micronutrient intake has a significant effect on the toxicity and carcinogenesis caused by various chemicals. This paper examines the effect of micronutrient status on the toxicity of four nonessential metals: cadmium, lead, mercury, and arsenic. Unfortunately, few studies have directly examined the effect of dietary deficiency or supplementation on metal toxicity. More commonly, the effect of dietary alteration must be deduced from the results of mechanistic studies. We have chosen to separate the effect of micronutrients on toxic metals into three classes: interaction between essential micronutrients and toxic metals during uptake, binding, and excretion; influence of micronutrients on the metabolism of toxic metals; and effect of micronutrients on secondary toxic effects of metals. Based on data from mechanistic studies, the ability of micronutrients to modulate the toxicity of metals is indisputable. Micronutrients interact with toxic metals at several points in the body: absorption and excretion of toxic metals; transport of metals in the body; binding to target proteins; metabolism and sequestration of toxic metals; and finally, in secondary mechanisms of toxicity such as oxidative stress. Therefore, people eating a diet deficient in micronutrients will be predisposed to toxicity from nonessential metals.

Animals↗
PubMed1995

Strategies for control of micronutrient malnutrition.

Micronutrient malnutrition, particularly vitamin A deficiency (VAD), iron deficiency anaemia (IDA) and iodine deficiency disorders (IDD), poses a serious threat to the health of vulnerable segments of population. Dietary Inadequacy is the primary cause of VAD and IDA, while poor iodine content of soil and water due to environmental iodine deficiency is the main determinant of IDD. Three major intervention strategies are available for the control of micronutrient malnutrition: supplementation of the specific micronutrients; fortification of foods with micronutrients; and horticulture intervention to increase production and nutrition education to ensure regular consumption of micronutrient rich foods. In India currently the national nutrition programmes being implemented for preventing these deficiencies are based on short term supplementation like periodic mega dosing of vitamin A, distribution of iron and folic acid tablets, and salt iodisation. Though these have been in operation for over two decades, there has been no perceptible biological impact on the prevalence of micronutrient malnutrition. Among the constraints, the most important are: lack of coordination, shortage of resources and manpower, inadequate and irregular supplies, lack of proper orientation and training to the functionaries, poor monitoring and supervision and absence of nutrition education. Integrated and multi-sectoral approaches are required to achieve the goals set under the National Nutrition Policy. These should include community-friendly nutrition education to increase awareness and motivation; active people's participation; food fortification; nutrient supplementation; nutrition oriented horticulture programmes; orientation of functionaries, and establishment of integrated micronutrient surveillance. Concerted and focussed efforts are needed to combat micronutrient malnutrition by the 2000 AD.

Anemia, Iron-Deficiency↗
PubMed1994

Daily micronutrient supplements enhance delayed-hypersensitivity skin test responses in older people.

A placebo-controlled double-blind trial of the effects of daily micronutrient supplements on circulating vitamin and trace metal concentrations and delayed-hypersensitivity skin test (DHST) responses was conducted. Subjects, aged 59-85 y, were randomly assigned to placebo (n = 27) or micronutrient (n = 29) treatment groups. DHST and circulating concentrations of nine micronutrients were measured before and after 6 and 12 mo of micronutrient ingestion. For the micronutrient group, there were statistically significant increases at 6 and/or 12 mo in the mean serum concentrations of ascorbate, beta-carotene, folate, vitamin B-6, and alpha-tocopherol. There was a significant increase at 12 mo in the number of subjects in the placebo group with one or more low concentrations. DHST responses to a panel of seven recall antigens were significantly increased at 12 mo in the micronutrient group but not the placebo group. This study demonstrates that daily supplementation with low-to-moderate doses of micronutrients can prevent low concentrations of some micronutrients and can improve DHST responses in healthy, independently living older adults.

Aged↗
PubMed1997

Non-milk extrinsic sugars in the diets of pre-school children: association with intakes of micronutrients, energy, fat and NSP.

Concern has been expressed that high dietary concentrations of non-milk extrinsic sugars (NMES) may potentially compromise nutrient intakes in population groups with low energy intakes (Department of Health, 1991). The objective of the present study was to examine data from the National Diet and Nutrition Survey of Children Aged 1.5 to 4.5 years (Gregory et al. 1995) for evidence of an inverse association between energy from NMES and micronutrient intakes, and if possible to quantify a level of NMES-energy at which micronutrient intakes may, theoretically, be compromised. Energy and nutrient intakes were compared across quintiles of NMES-energy for boys (n 848) and girls (n 827). As the concentration of NMES increased, energy intake rose (in boys only) while percentage energy from fat fell from 40 to 32% across quintiles 1 to 5. Intakes of most micronutrients also fell, while intakes of vitamin C rose. Mean intakes of most micronutrients (Ca, thiamin, riboflavin, niacin, folate and vitamin C) were adequate in comparison with dietary reference values. However, intakes of Fe, Zn and vitamin D were low at all levels of NMES-energy and fell below the estimated average requirement for Fe and Zn for NMES concentrations exceeding 24% of energy. Lower Intakes of milk, meat, bread and vegetables, and higher intakes of fruit juice largely explain the observed trends in micronutrient intake. It is concluded that the inverse association of NMES with micronutrient intakes is of most significance for the 20% of children with diets highest in NMES. However, further work is required to establish whether the associations observed have biological significance with regard to micronutrient status.

Animals↗
PubMed1996

Prospective study of serum micronutrients and ovarian cancer.

BACKGROUND: Antioxidant micronutrients, such as alpha-tocopherol (vitamin E), the carotenoids, and selenium, may protect against the development of cancer by preventing free radical damage at the cellular level. PURPOSE: A nested case--control study was conducted among donors to a serum bank to examine the association between levels of serum micronutrients and/or cholesterol and the development of ovarian cancer. METHODS: In 1974, sera were collected from 20,305 residents of Washington County, MD, over a 4-month period and stored at -70 degrees C. Serum micronutrient concentrations of women who developed ovarian cancer (case subjects, n = 35) were compared with those of women who remained free of cancer and who were matched to case subjects on age and menopausal status (control subjects, n = 67). Serum levels of retinol (vitamin A), alpha- and beta-carotene (the major provitamin A), lycopene (a carotenoid), and alpha- and gamma-tocopherol were measured using high-performance liquid chromatography. Serum selenium was measured by neutron activation analysis. Cholesterol was measured by enzymatic assay. The data were categorized into thirds and conditional logistic regression analyses were performed to determine the association between prediagnostic serum cholesterol and micronutrient levels and the development of ovarian cancer; matched odds ratios (ORs) were determined from these regression analyses. P values for trend and for interaction were calculated with the use of two-sided likelihood ratio tests. RESULTS: Higher serum alpha-tocopherol levels were associated with an increased risk of ovarian cancer (P for trend = .04); however, this association diminished after adjustment for cholesterol. Women with higher serum cholesterol levels had an increased risk of ovarian cancer compared with women in the lowest third of cholesterol levels (OR = 3.2; 95% confidence interval = 0.9-11.3). The association between serum cholesterol levels and the risk of ovarian cancer was examined, stratifying by micronutrient level. The general pattern observed was an increased risk of ovarian cancer associated with cholesterol levels greater than 200 mg/dL, regardless of the micronutrient level. Serum selenium was associated with a decreased risk of ovarian cancer only among case participants diagnosed 4 or more years after blood collections (P for trend = .02). Concentrations of carotenoids and retinol were not associated with the development of ovarian cancer. CONCLUSIONS: Selenium may have a protective role against the development of ovarian cancer. Higher serum cholesterol levels were associated with an increased risk of developing ovarian cancer; an association that persisted regardless of serum micronutrient level. IMPLICATIONS: Given the small size of this study and the inconsistency of results among the few prospective studies of ovarian cancer conducted to test these associations, replications of these findings are highly desirable.

Carotenoids↗
PubMed1996

Micronutrients as chemopreventive agents.

The concept of chemoprevention of cancer by micronutrients is based upon evidence from human epidemiology and from studies of animal carcinogenesis models for cancer-inhibiting potential of certain minerals and vitamins. These micronutrients are diverse with respect to chemical structures and physiological effects, and include calcium, selenium, carotenoids, and vitamins A, C, D and E. The dietary intake of various micronutrients has been observed to alter significantly the incidence and mortality of a variety of human cancers including those of the oesophagus, stomach, colon, breast and cervix. Studies of laboratory animal models have also provided relevant mechanistic and efficacy data on the role of specific micronutrients as well as minor non-nutrients of dietary origin in the carcinogenic process. Micronutrients and such minor non-nutrients have been found to modulate the formation and bioactivation of carcinogens, modify the promotion and progression of carcinogenesis, alter cellular and host defences, and affect cellular differentiation-ultimately leading to variations in tumour incidences. Our understanding of biochemical and biological mechanisms of carcinogenesis and of inhibition of initiation, promotion and progression by particular micronutrients-both naturally occurring forms and their synthetic analogues-has made it possible to develop strategies for clinical intervention by these agents. It is possible that intervention with individual micronutrients and minor non-nutrients, and/or with a combination of such compounds with different modes of action, will prevent, delay or reverse the process of carcinogenesis and thus reduce the incidence of and mortality due to human cancers. A number of Phase II clinical trials have been initiated with the objective of identifying and evaluating intermediate biomarkers that will be used as surrogate end points for cancer. Several surrogate end points have been standardized and validated for their specificity. The results are very encouraging.

Animals↗
PubMed1998

Micronutrients prevent cancer and delay aging.

Approximately 40 micronutrients are required in the human diet. Deficiency of vitamins B12, folic acid, B6, niacin, C, or E, or iron, or zinc, appears to mimic radiation in damaging DNA by causing single- and double-strand breaks, oxidative lesions, or both. The percentage of the US population that has a low intake (< 50% of the RDA) for each of these eight micronutrients ranges from 2% to > or = 20%; half of the population may be deficient in at least one of these micronutrients. Folate deficiency occurs in approximately 10% of the US population, and in a much higher percentage of the poor. Folate deficiency causes extensive incorporation of uracil into human DNA (4 million/cell), leading to chromosomal breaks. This mechanism is the likely cause of the increased cancer risk, and perhaps the cognitive defects associated with low folate intake. Some evidence, and mechanistic considerations, suggest that vitamin B12 and B6 deficiencies also cause high uracil and chromosome breaks. Micronutrient deficiency may explain, in good part, why the quarter of the population that eats the fewest fruits and vegetables (five portions a day is advised) has approximately double the cancer rate for most types of cancer when compared to the quarter with the highest intake. Eighty percent of American children and adolescents and 68% of adults do not eat five portions a day. Common micronutrient deficiencies are likely to damage DNA by the same mechanism as radiation and many chemicals, appear to be orders of magnitude more important, and should be compared for perspective. Remedying micronutrient deficiencies is likely to lead to a major improvement in health and an increase in longevity at low cost. Aging appears to be due, in good part, to the oxidants produced by mitochondria as by-products of normal metabolism. In old rats mitochondrial membrane potential, cardiolipin levels, respiratory control ratio, and overall cellular O2 consumption are lower than in young rats, and the level of oxidants (per unit O2) is higher. The level of mutagenic aldehydes from lipid peroxidation is also increased. Ambulatory activity declines markedly in old rats. Feeding old rats the normal mitochondrial metabolites acetyl carnitine and lipoic acid for a few weeks, restores mitochondrial function, lowers oxidants to the level of a young rat, and increases ambulatory activity. Thus, these two metabolites can be considered necessary for health in old age and are therefore conditional micronutrients. This restoration suggests a plausible mechanism: with age-increased oxidative damage to proteins and lipid membranes causes a deformation of structure of key enzymes, with a consequent lessening of affinity (Km) for the enzyme substrate; an increased level of the substrate restores the velocity of the reaction, and thus restores function.

Aging↗
PubMed1999

Micronutrients and the pathogenesis of human immunodeficiency virus infection.

Micronutrient deficiencies may be common during human immunodeficiency virus (HIV) infection. Insufficient dietary intake, malabsorption, diarrhoea, and impaired storage and altered metabolism of micronutrients can contribute to the development of micronutrient deficiencies. Low plasma or serum levels of vitamins A, E, B6, B12 and C, carotenoids, Se, and Zn are common in many HIV-infected populations. Micronutrient deficiencies may contribute to the pathogenesis of HIV infection through increased oxidative stress and compromised immunity. Low levels or intakes of micronutrients such as vitamins A, E, B6 and B12, Zn and Se have been associated with adverse clinical outcomes during HIV infection, and new studies are emerging which suggest that micronutrient supplementation may help reduce morbidity and mortality during HIV infection.

Avitaminosis↗
PubMed1997

A preliminary report: effects of zinc and micronutrient repletion on growth and neuropsychological function of urban Chinese children.

OBJECTIVE: Zinc is essential for growth and cognition of experimental animals. Past research found zinc repletion improved growth of stunted Chinese children. Therefore we measured effects of zinc repletion on growth and neuropsychological functions of children. DESIGN: Double-blind randomized controlled treatment trial. SETTING: Elementary schools in low income districts of Chongqing, Qingdao and Shanghai. SUBJECTS: Three hundred-seventy-two 6 to 9 year old first graders. INTERVENTIONS: Treatments were 20 mg zinc, 20 mg zinc with micronutrients, or micronutrients alone. The micronutrient mixture was based on guidelines of the US NAS/NRC. Treatments were assigned to classrooms of 40 or more children each, and administered by teachers 6 days per week for 10 weeks. MEASURES OF OUTCOME: Changes in knee height and neuropsychological functions. RESULTS: Zinc alone had the least effect on growth while zinc with micronutrients had the largest effect; micronutrients alone had an intermediate effect. Zinc-containing treatments improved neuropsychological functions, but micronutrients alone had little effect. CONCLUSIONS: The findings confirm the essentiality of zinc for growth of children, and show, for the first time, the essentiality of zinc for neuropsychological functions of children. In addition, the need for repletion of other potentially limiting nutrients in studies examining the effects of specific nutrients on growth and neuropsychological functions was confirmed.

Analysis of Variance↗
PubMed1999

Separate and joint effects of micronutrient deficiencies on linear growth.

Recent studies have investigated the effect of micronutrient deficiencies on growth stunting, with special attention toward the effect of zinc, iron, vitamin A and iodine deficiencies. In Mexico, the prevalence of growth stunting in children <5 y old is approximately 24%; it is higher in rural areas and lower in urban areas. In an initial study, the effect of zinc and/or iron supplementation on linear growth was investigated in a longitudinal, placebo-controlled design. After 12 mo of supplementation, there was no difference between the groups supplemented with zinc, iron or zinc plus iron and the placebo group. At baseline, 82% of the children in this study were deficient in at least two out of the five micronutrients that were determined, and 73% were anemic. In another study, a mixture of those micronutrients that were documented to be lacking in Mexican children was formulated in a supplement and given to Mexican children over a period of 12 mo in a longitudinal, placebo-controlled, supplementation design. Children in the low and medium socioeconomic status grew about 1 cm more than similar children in the placebo group. This difference was not found in children of high socioeconomic status. It is suggested that, in most cases, growth stunting is associated with marginal deficiencies of several micronutrients and that in populations with multiple micronutrient deficiencies, the effect on linear growth of supplementation with single nutrients will not be significant. Supplementation with multiple micronutrients is expected to be more effective, but even in that case the actual increment in height was less than the expected potential increment.

Child, Preschool↗
PubMedDate not supplied

[What is known about micronutrients in Mexico].

OBJECTIVE: To update the information on micronutrients in Mexico regarding: 1. The research lines according to priority of the micronutrient, subjects affected, and its focus (basic, clinical, epidemiological, operational). 2. The laboratory capacity available for micronutrient assays. MATERIAL AND METHODS: We analyzed review articles of what has been published on micronutrients in Mexico since 1950. We also gathered information by questionnaire from the 16 research groups working in Mexico in the area of micronutrients. RESULTS: We generated tables summarizing the situation of the six micronutrients which we identified as the most problematic in Mexico (vitamins A and C, and iron, iodine, zinc and calcium). CONCLUSIONS: We reached 10 conclusions related to populations of study, research line priorities, and desirable operational studies.

Adult↗
PubMedDate not supplied

Micronutrient status in patients receiving home parenteral nutrition.

Administration of home parenteral nutrition (HPN) to patients with intestinal failure requires attention to caloric content of feeds, fluid, electrolyte balance, and micronutrient status. Peripheral blood estimations of vitamins and trace elements may be abnormal, but their clinical significance in relation to deficiency or toxicity states is not always clear. We sought to determine the incidence and nature of clinical micronutrient abnormality in our HPN program. Clinical assessment and case record review of 49 patients actively receiving HPN was undertaken, and, in 32 of these patients, serum micronutrient levels were assayed. Clinical evidence of micronutrient deficiency was identified in 16 patients (33%). Iron deficiency anemia occurred in 14 patients which resolved after iron supplementation in all except 1 patient who had persistent intestinal blood loss. Anemia was precipitated in six patients by identifiable clinical events (acute gastrointestinal disease in five and menorrhagia in one), and in two others folate deficiency coexisted. Biotin deficiency developed in three patients, manifested by dry eyes and angular cheilitis or hair loss. Vitamin A deficiency resulting in visual disturbance developed in one patient who was not receiving multivitamin supplements at that time. Serum levels of zinc, copper, selenium, manganese, vitamin A, and vitamin E were measured in 32 patients. No patient had normal levels of all six micronutrients. Nevertheless, there was no clinical evidence of toxicity or deficiency in any of these patients at the time assays were performed. In conclusion, abnormalities of micronutrient status are common in HPN patients, but serious sequelae appear to be unusual.

Adult↗
PubMed1994

Dietary intake and micronutrient status of adolescents: effect of vitamin and trace element supplementation on indices of status and performance in tests of verbal and non-verbal intelligence.

Relationships between micronutrient intake and status, and micronutrient status and performance in tests of intelligence were investigated in a group of adolescents (13-14 years old). Dietary intakes were assessed using a 7 d weighed dietary record method, coupled with the collection of duplicate diets. Vitamin and trace mineral intakes calculated using food composition tables were compared with those obtained by direct analysis of duplicate diets. Micronutrient status was judged via a range of biochemical indices measured in blood samples taken after a 12-15 h fast. Blood samples were taken both before and after a 16-week period of vitamin and trace mineral supplementation. Individual tests of verbal and nonverbal intelligence were also performed pre- and post-supplementation. The results of this study indicate that the use of food table data may lead to substantial over- or underestimation of the intake of several micronutrients. In general, the total calculated or analysed amount of a specific micronutrient consumed did not adequately predict status, as judged by a range of biochemical indices. There were significant changes in status measurements over the 16-week study period, irrespective of supplementation, and these changes were markedly influenced by the initial status of the subject. There was no effect of supplementation on performance in tests of intelligence. However, there was a significant association between plasma ascorbic acid and initial non-verbal intelligence quotient (IQ) in the boys, and between whole blood glutathione peroxidase (EC 1.11.1.9) activity and non-verbal and verbal IQ in both sexes. These findings are discussed in relation to other recent studies of the influence of micronutrient supplementation on the psychological performance of children.

Adolescent↗
PubMed1994

Micronutrients and cancer aetiology: the epidemiological evidence.

Micronutrient deficiencies occur most commonly in poor countries and, therefore, are most likely to be associated with cancers common in these countries. Epidemiological studies are hampered by inaccurate measurement of micronutrient intake and by the correlations between intakes of many nutrients. The strongest evidence for a protective effect of micronutrients is for oesophageal cancer. The identity of the micronutrients is not certain, but may include retinol, riboflavin, ascorbic acid and Zn; alcohol, smoking and dietary nitrosamines increase the risk for oesophageal cancer. For stomach cancer there is good evidence that fruit and vegetables are protective. The protective effect of these foods might be largely due to ascorbic acid, but other nutrients and non-nutrients may also be important; the risk for stomach cancer is increased by salt, some types of preserved foods, and by infection of the stomach with the bacterium Helicobacter pylori. The risk for lung cancer appears to be reduced by a high intake of fruit and vegetables, but it is not clear which agents are responsible and the major cause of lung cancer is cigarette smoking. Diet is probably the major determinant of the risk for colo-rectal cancer; there is evidence that fruit and vegetables and fibre reduce risk and that meat and animal fat increase risk, but there is no convincing evidence that these relationships are mediated by micronutrients. The risk for cervical cancer is inversely related to fruit and vegetable consumption and, therefore, to consumption of carotenoids and ascorbic acid, but the major cause of this cancer is human papillomavirus and it is not yet clear whether the dietary associations indicate a true protective effect or whether they are due to confounding by other variables. The evidence that micronutrients are important in the aetiology of either breast cancer or prostate cancer is weak, but the possible roles of 1,25-dihydroxycholecalciferol and alpha-tocopherol in prostate cancer require further study.

Diet↗