By Dr. Joanmarie Pellegrini, Eastern Maine Medical Center
Most of us learned in school that Vitamin D is important for our bone health and that we get it from being in the sun. This is true. The sun on our exposed skin, along with our liver and kidneys, acts to convert the inactive molecule to the active vitamin. We can also get the active vitamin in our diet. Many foods, including milk, are supplemented with vitamin D. Vitamin D is critical in regulating our calcium metabolism. We have known for decades that vitamin D is critical for bone development. However, there is now increasingly significant research into the other biologic actions of this vitamin. These include the immune system (both the innate and adaptive), pancreas (i.e. diabetes) and metabolic homeostasis, heart-cardiovascular (heart disease and hypertension), muscle and brain systems (i.e. dementia), as well as the control of the cell cycle, and thus of the disease process of cancer.
I have been telling my patients for years that if they have a problem with colon polyps, that taking Caltrate (calcium) and aspirin my help to reduce the number of polyps. New evidence shows that these same patients would probably also benefit from Vitamin D supplementation.
Several conditions such as tuberculosis, psoriasis, eczema, Crohn’s disease, chest infections, wound infections, influenza, urinary tract infections, eye infections and wound healing may benefit from adequate circulating vitamin D levels.
Scientists and nutritionists from many countries agree that at present about half of elderly North Americans and Western Europeans and probably also of the rest of the world are not receiving enough vitamin D to maintain healthy bone. This despite very well publicized national guidelines and supplementing our milk and orange juice. It is unclear exactly why our vitamin D levels are low. It could be from reduced dietary intake or less sun exposure or, more likely, a combination. We all live in a northern climate and this means we have less sun exposure than people living near the equator. Also, we tend to use sun screen which blocks the sun’s ability to help our skin make vitamin D.
So, should you take a vitamin D supplement? You should evaluate how often you are outside when it is sunny. Is it at least 10 minutes a day without sunscreen? How much vitamin D are you getting in your diet? Dietary sources that are high in vitamin D are milk, orange juice (if the carton says it has added vitamin D), and fatty fish (such as mackerel and salmon). If you think you may not be getting enough, then a supplement of 1000 IU a day during the summer and 200 IU during the winter may be beneficial. If you are someone who seems to get every virus that goes through your office or school, then some experts believe this may be a sign of being relatively vitamin D deficient and that you’d benefit from taking extra vitamin D. If you are on medications or have liver or kidney disease, then you should discuss this issue with your physician before starting vitamin D supplementation.
Dr. Pellegrini is a general surgeon specializing in trauma cases at Eastern Maine Medical Center in Bangor.