Experts Detail Unexpected Reasons for Widespread Vitamin D Deficiency in the U.S.
Despite vitamin D being known as the 'sunshine vitamin,' a significant portion of the global population, approximately 60%, suffers from vitamin D deficiency, even during summer months. Dr. Michael Holick, a professor of medicine at Boston University Chobanian and Avedisian School of Medicine, highlights that vitamin D functions as a hormone crucial for bone health, muscle function, and potentially cancer prevention, immune function, cardiovascular disease, and dementia. Experts, including Dr. Kendall F. Moseley of Johns Hopkins Metabolic Bone and Osteoporosis Center and Dr. Leila Khan, an endocrinologist at Cleveland Clinic, point to several unexpected reasons for this deficiency. These include the difficulty of obtaining sufficient vitamin D from diet alone, insufficient direct sun exposure even in summer due to time of day, pollution, and sunscreen use, decreased production with age, darker skin tones, and certain chronic health conditions or medications. Most people need 1,000 to 2,000 IU per day, but ... 
