Dr. Manoj Sharma-
Dr. Sharma is a Professor and Chair of the Social and Behavioral Health Department and an Adjunct Professor in Internal Medicine at the University of Nevada, Las Vegas (UNLV). He is a global expert in health promotion.
A recent change suggested by the Endocrine Society calls for stopping routine checks for Vitamin D and limiting Vitamin D supplementation beyond the recommended levels only to high-risk groups. These guidelines have recently been published in the Journal of Clinical Endocrinology and Metabolism. These recommendations have sparked controversy in medical circles. Some support these guidelines while others oppose it.
What is Vitamin D and what is its role in the human body? Vitamin D (also known as calciferol) is a fat-soluble vitamin. It is produced when ultraviolet rays from sunlight fall on the skin. It is also present in some foods, used as an additive, and available over the counter as a supplement. Its role in the human body is to enhance calcium absorption and maintain optimum blood levels of calcium and phosphate that promote bone health. Its deficiency in children can lead to rickets in children and osteomalacia in adults. The optimum level of Vitamin D in the blood is between 20-50 ng/mL. Excess of it is also bad and can lead to elevated calcium levels in the blood, kidney stones, calcification in various parts of the body, kidney failure, and even death. The recommended daily allowance for Vitamin D for adults is 15 mcg or 600 IU.
So, what is the controversy? Low levels of Vitamin D in observational studies have been found to be associated with cancer, heart disease, diabetes, falls, and overall increased death rates. In observational studies, researchers follow groups of people over time and look for outcomes of interest. However, when randomized controlled trials (RCTs) which require participants to take supplements and compare that with placebo have been conducted this association has been found to be invalid. RCTs are sometimes considered gold standards for causality. Hence, the role of routine Vitamin D screening and supplementation has become questionable. So, the supporters of these new guidelines rely on this scientific evidence. They advocate Vitamin D screening and supplementation only in high-risk groups that include children below 18 years, pregnant people, adults over 75 years of age, and those with prediabetes.
On the other hand, there is a small group perhaps backed by industry that opposes these guidelines. The global Vitamin D market in 2021 stood at USD 603.67 million and was expected to grow by 6.1% between 2022 and 2030. This group advocates that a large proportion of the world’s population is facing a deficiency of Vitamin D due to a lack of a healthy diet and very little exposure to the sun. Hence, this group advocates that regular testing for Vitamin D and its supplementation should be routinely undertaken.
So, what should the general public make out of this? First, consuming foods rich in Vitamin D including cod liver oil, trout, salmon, sardines, tuna, mushrooms, and fortified milk should be considered. Second, healthy lifestyle measures such as eating a variety of foods, exercising outdoors, and getting enough exposure to the sun should be helpful. Finally, one should discuss the necessity of Vitamin D screening and supplementation with one’s primary care provider and together arrive at a judicious decision.
