Supplement News

Somewhat alarmingly, findings also showed that in 2013–2014, the prevalence of supplemental intake of 4,000 IU or more was 3.2%, compared with 0.1% before 2005–2006.
The Institute of Medicine of the National Academies sets the safe daily upper limit for daily vitamin D intake at 4,000 IU. Going consistently higher raises the risk of adverse effects, including blood vessel calcification, which can eventually damage the heart, liver and other organs. With winter gloom upon us, it’s important to be cognizant of getting enough vitamin D through food and supplementation, since deficiencies are still widely reported, but overdosing isn’t the answer. For most people, daily supplementation of 1,000 IU should suffice, but precise amounts should be discussed with a physician.