Natural Products Association questions study on use of multivitamin’s by postmenopausal women
WASHINGTON A new study published Monday claiming that multivitamin use by postmenopausal women does little to improve their risk of mortality fails to take into account important dietary factors or accurately grasp how dietary supplements and health claims are regulated by the Food and Drug Administration, the Natural Products Association charged Monday afternoon.
According to the study, which was published in the Feb. 9 issue of Archives of Internal Medicine, postmenopausal women who take multivitamins have the same risk of dying from “most common cancers, cardiovascular disease or of any cause as women who do not take multivitamin supplements.”
“While cohort and observational studies like these can be important, they in no way constitute convincing or conclusive evidence,” stated Daniel Fabricant, VP scientific and regulatory affairs for NPA. “This study fails to tell the whole story about the positive effect that vitamins and minerals can have on health. It also does not take into account important factors such as nutrients gained through diet.”
Fabricant said it is “unprincipled” that the authors arbitrarily lumped supplement types into generalized categories that do not represent nutrient intake accurately. And when coupled with the fact that nutrient intake through the diet was not accounted for, Fabricant explained, the study has no means of establishing a baseline for which to draw any comparisons or eliminate bias.
Also troubling was the author’s apparent lack of understanding about how dietary supplements are regulated, NPA stated.
“The authors seem to be confused or unaware of how supplements are regulated and exactly what constitutes a health claim authorized by the FDA,” Fabricant said. “For example, they cite that there is only one supplement, folic acid, worthy of a public health recommendation by way of a health claim. However, even a cursory visit to the FDA’s Web site would have revealed that other nutrients and dietary ingredients, including the very calcium and vitamin D that they studied, also have FDA-authorized health claims.”
“Taken as whole, the research on dietary supplements in the prevention of chronic diseases, is strong and consistent,” Fabricant said. “To suggest that taking vitamins and minerals with a demonstrated health benefit is unnecessary sends the wrong public health message.”
Study finds no cancer risks from hormone replacement therapy within first two years
ATLANTA The American Cancer Society last week announced that there may be a two-year “safe period” for the use of hormone replacement therapies estrogen and progesterone.
According to a recently published study, new findings on the role of hormone use on the risk of breast cancer confirmed that the use of estrogen plus progesterone increases the risk of both ductal and lobular breast cancer by far more than estrogen-only, but found that the increased risk for ductal cancers observed in long-term past users of hormone replacement therapy drops off substantially two years after hormone use is stopped. They also found the risk associated with use of estrogen and progesterone increases significantly and substantially within three years of beginning hormone use. The data showed no increased risk for women who used estrogen and progesterone for less than two years, potentially identifying a “safe” period for estrogen and progesterone use.
The study appears in CANCER, a peer-reviewed journal of the American Cancer Society.
Previous studies have shown that hormone replacement therapy after menopause increases the risk of breast cancer and that use of a regimen that includes both estrogen and progesterone is more detrimental for the breast than the use of estrogen alone. But more data from large prospective studies are needed to fully characterize the impact of exogenous hormones on breast cancer incidence by type of hormone preparation and histology of the cancer.
Research finds vitamin D helps prevent multiple sclerosis
SAN FRANCISCO Researchers have found evidence that a direct interaction between vitamin D and a common genetic variant alters the risk of developing multiple sclerosis. The research, published Friday in the open-access journal PLoS Genetics, suggests that vitamin D deficiency during pregnancy and the early years may increase the risk of the offspring developing MS later in life.
“Our study implies that taking vitamin D supplements during pregnancy and the early years may reduce the risk of a child developing MS in later life,” stated lead author Sreeram Ramagopalan. “Vitamin D is a safe and relatively cheap supplement with substantial potential health benefits. There is accumulating evidence that it can reduce the risk of developing cancer and offer protection from other autoimmune diseases.”
The researchers found that proteins activated by vitamin D in the body bind to a particular DNA sequence lying next to the DRB1*1501 variant, in effect switching the gene on.
“In people with the DRB1 variant associated with MS, it seems that vitamin D may play a critical role,” stated co-author Julian Knight. “If too little of the vitamin is available, the gene may not function properly.”
“We have known for a long time that genes and environment determine MS risk,” stated Professor George Ebers, University of Oxford. “Here we show that the main environmental risk candidate – vitamin D – and the main gene region are directly linked and interact.”
MS is the most common disabling neurological condition affecting young adults. More than 85,000 people in the United Kingdom and 2.5 million worldwide are thought to suffer from the condition, which results from the loss of nerve fibres and their protective myelin sheath in the brain and spinal cord, causing neurological damage.
The causes of MS are unclear, but it has become evident that both environmental and genetic factors play a role. Previous studies have shown that populations from Northern Europe have increased MS risk if they live in areas receiving less sunshine. This supports a direct link between deficiency in vitamin D, which is produced in the body through the action of sunlight, and increased risk of developing the disease.PLoS Genetics is published by the Public Library of Science, a non-profit organization of scientists and physicians committed to making the world’s scientific and medical literature a freely available public resource.