Recent Findings on Vitamin D and What It All Means

JoAnn Manson, MD is a professor of medicine and epidemiology at the Harvard Medical School and Brigham and Women’s Hospital where she directed the Vitamin D and Omega 3 trial known as VITAL. She was interviewed about the pros and cons of vitamin D supplementation and what is science and fact.

The VITAL study is one of the first large, randomized studies to study vitamin D and its effect on health. Dr. Manson points out that previous observational studies which cannot prove cause and effect directly led to the belief that vitamin D is a panacea and cure all for many chronic conditions such as cancer, cardiovascular disease, diabetes, bone fractures, cognitive decline, and depression. She said that the randomized studies do not support this conclusion, but she feels vitamin D remains essential to good health. It is so essential that she says we need exceedingly small doses to achieve the health outcomes we desire.

Most of it can be obtained in your diet (read labels) and by exposing yourself to sunshine a few minutes each day. Therefore, the National Academy of Medicine and US Preventive Services Task Force and many other professional organizations have advised against widespread screening for vitamin D deficiency and blanket supplementation.

Her VITAL study did not show a reduction in major health issues with supplementation of vitamin D except in two instances. Vitamin D Supplementation resulted in a 22% reduction in autoimmune diseases (Rheumatoid Arthritis and Psoriasis) and a 17% in advanced metastatic cancers at doses of 400- 800 IUs daily. In the VITAL study they used 2000 IU daily. They believe the vitamin D reduced the inflammatory process and damage.

Some scientists have hypothesized that vitamin D supplementation can reduce the severity of COVID-19 infections. That randomized study called VIVID (vitamin D for Covid Trials) is near completion using 3000 IU per day. The data should be available in the next few weeks.

When asked what Dr. Manson suggests for her own clinical patients, she admitted she suggests ingesting one thousand – 2000 IU per day hopefully getting most of it in her diet. That dosage has been shown to be safe during the VITAL trial. She went on to note vitamin D is found in fresh fatty fish and wild mushrooms. Most cereals, dairy products and some beverages are fortified with vitamin D.