paywalled: Dietary Supplements and Cancer Prevention: Balancing Potential Benefits Against Proven Harms

Dietary Supplements and Cancer Prevention: Balancing Potential Benefits Against Proven Harms

Abstract

Nutritional supplementation is now a multibillion-dollar industry, and about half of all US adults take supplements. Supplement use is fueled in part by the belief that nutritional supplements can ward off chronic disease, including cancer, although several expert committees and organizations have concluded that there is little to no scientific evidence that supplements reduce cancer risk. To the contrary, there is now evidence that high doses of some supplements increase cancer risk. Despite this evidence, marketing claims by the supplement industry continue to imply anticancer benefits. Insufficient government regulation of the marketing of dietary supplement products may continue to result in unsound advice to consumers. Both the scientific community and government regulators need to provide clear guidance to the public about the use of dietary supplements to lower cancer risk.

abstract: Vitamins, minerals, essential fatty acids and colorectal cancer risk in the United Kingdom Dietary Cohort Consortium - 2012 - International Journal of Cancer

Vitamins, minerals, essential fatty acids and colorectal cancer risk in the United Kingdom Dietary Cohort Consortium - International Journal of Cancer 

Abstract

The risk for colorectal cancer may be influenced by the dietary intake of various vitamins, minerals and essential fatty acids. We conducted a pooled analysis of dietary data collected using food diaries in seven prospective studies in the United Kingdom Dietary Cohort Consortium. Five hundred sixty-five cases of colorectal cancer were matched with 1,951 controls on study centre, age, sex and recruitment date. Dietary intakes of retinol, vitamin A, thiamin, riboflavin, vitamin B6, folate, vitamin B12, vitamin D, calcium, iron, magnesium, potassium, n − 6 fatty acids, n − 3 fatty acids and the ratio of n − 6 to n − 3 fatty acids were estimated and their associations with colorectal cancer examined using conditional logistic regression models, adjusting for exact age, height, weight, energy intake, alcohol intake, fiber intake, smoking, education, social class and physical activity. There were no statistically significant associations between colorectal cancer risk and dietary intake of any of the vitamins, minerals or essential fatty acids examined.

open access: Perspective: Assessing Supplement Safety — The FDA's Controversial Proposal — NEJM

"Each year, Americans spend more than $28 billion on supplements assuming that they are both safe and effective. More than 100 million Americans consume vitamins, minerals, herbal ingredients, amino acids, and other naturally occurring products in the form of dietary supplements....."

Cancer Causes and Control - Dietary calcium and magnesium intake in relation to cancer incidence and mortality in a German prospective cohort

"This prospective cohort study provides no strong evidence to support that high dietary calcium and magnesium intake in the intake range observed in a German population may reduce cancer incidence or mortality."

abstract: Vitamin/mineral supplementation and cancer, cardiovascular, and all-cause mortality in a German prospective cohort (EPIC-Heidelberg)

Role of Vitamin and Mineral Supplementation and Aspirin Use in Cancer Survivors — JCO

Note: a recent study indicated a beneficial effect of aspirin use in Lynch Syndrome patients but not in colon cancer patients (those w/o a mutation), search blog for further information on this specific issue "The potential beneficial or adverse effects of dietary supplements and aspirin in survivors of cancer warrant further study."

Role of Vitamin and Mineral Supplementation and Aspirin Use in Cancer Survivors (abstract)

Note: abstract does not reference ovarian cancer "The potential beneficial or adverse effects of dietary supplements and aspirin in survivors of cancer warrant further study."