Vitamins & Supplements

A. Alice H. Lichtenstein, DSc, executive editor of Tufts Health & Nutrition Letter, answers: “Optimal health is dependent on consuming the appropriate quantity of nutrients and energy (calories). When scientists learned how to separate nutrients from foods or synthesize them in a laboratory, there was hope we could prevent malnutrition and maximize health simply by […]

Researchers from Tufts University and Tufts Medical Center have found that taking vitamin D3 supplements has no effect on serum cholesterol. Their randomized controlled trial, published recently in the American Journal of Clinical Nutrition, does not support results from observational studies that found an association between serum levels of vitamin D and LDL or HDL […]

A study published recently in the New England Journal of Medicine found that vitamin D supplementation during the prenatal period alone did not influence...

A. Kelly Siverhus, a dietetic intern at the Frances Stern Nutrition Center, answers: “Adequate iron intake is essential for the transport of oxygen from...

While observational studies have suggested that low blood levels of vitamin D are associated with higher risk of developing type 2 diabetes, a clinical trial recently published in The American Journal of Clinical Nutrition found that supplementation with vitamin D3 had no effect on insulin action in people with prediabetes.

Q. Are prunes high in vitamin K? I am on blood thinners and was told I need to limit vitamin K intake.

Vitamin B12 plays many crucial roles in the body. It is involved in neurologic function, red blood cell production, DNA synthesis, and a number of important chemical reactions. Vitamin B12 deficiency, while not common, can cause megaloblastic anemia (a disorder of the red blood cells that can cause symptoms such as fatigue, pale skin, and lightheadedness) and neurological and cognitive disorders.

A study published recently in JAMA Network Open found that very high intake of vitamins B6 and B12 from supplements (much higher than the Recommended Dietary Allowances) was associated with increased risk of hip fracture in women. In this prospective cohort study, 75,864 postmenopausal women in the U.S. were followed for 30 years.

A randomized controlled intervention trial published recently in the American Journal of Clinical Nutrition found that supplementation with vitamin D had no significant effect on depressive symptoms or physical functioning in older persons with low vitamin D status.

The B vitamin folate (B9) is found naturally in a variety of foods including vegetables (especially dark leafy greens), fruits and fruit juices, nuts, beans, peas, seafood, eggs, dairy products, meat, poultry, and whole grains.