Dr. Chris Magryta column: Vitamin D and the sun
Published 12:00 am Monday, June 30, 2008
We all love sunny days and the effect the sun has on our psyche and feelings of wellness. For centuries, humans have lived by the sun, whether by its regulating our sleep cycle or producing our natural foods.
Yet recently we have shunned the sun’s direct effects on our bodies by avoiding it and using sun-blocking agents and lotions. Skin cancer during the ’60s and ’70s ushered in a period of phobia. True to our nature, many chose the extremist way of dealing with the problem: total avoidance.
This campaign has helped produce a generation of vitamin D-deficient Americans.
In the recent past, the medical community believed that vitamin D simply controlled calcium and phosphorus metabolism and bone health. Recent studies are showing this to be the tip of the iceberg. Vitamin D stimulates the immune system from birth and plays a role in natural immune system function. Inadequate levels of vitamin D are being linked to autoimmune disease, like multiple sclerosis, and cancers. An excellent study by Dr. Gerard E. Mullen from Johns Hopkins University delineates the connections.
These diseases are noted to be more common at northern latitudes on the globe where sun exposure is limited by temperature and the sun’s height in the sky. After much review, the link appears to be vitamin D deficiency and limited UVB sun exposure. Our lifestyles have increased sedentary indoor work and recreation, thereby reducing sun exposure. Sunscreens also effectively reduce the sun’s beneficial effects. According to the National Institutes of Health, there is an inverse relationship between vitamin D levels in the body and cancer. It is time for everyone to pay attention to this ever-important hormone made in our skin.
The goal of prevention of skin cancer should be to avoid sunburns, which are noted to be a risk factor for cancer. Exposure to 15 to 30 minutes of direct sun a day has never been shown in any way to be dangerous. However, the beneficial effects on vitamin D levels are well known at roughly 10,000 to 15,000 IU of vitamin D during this brief exposure. You would need 100 cups of milk to equal this amount! Not being a calf, I will pass on the milk in favor of the sun.
In a recent lecture by the esteemed Dr. Michael F. Holick, a dermatologist and vitamin D specialist from Boston University, he espoused prudent sun exposure and the evaluation of one’s vitamin D status, especially if one suffers from bone pain, muscle weakness, chronic fibromyalgia, osteoporosis, irritable bowel syndrome and other non-specific inflammatory diseases. The recommendations for supplemental vitamin D are also increasing, especially as one ages. The skin of the elderly is less able to synthesize vitamin D through sun exposure. Ask your primary care doctor for the most current information on this topic.
Diet and exercise also need to be addressed. As always, I believe part of a healthy life includes a balanced meal pattern and exercise regimen. The anti inflammatory diet appears to be the most sensible and scientific today. Part of this diet includes eating fish; three ounces of salmon will provide 400IU of vitamin D. Weight bearing exercise is also a part of a healthy aging plan. Exercise has a beneficial effect on prevention of bone loss and also improves mental wellness.
Children who are exclusively breastfed may require vitamin D supplementation. The American Academy of Pediatrics recommends 200IU of vitamin D per day in these infants.
As the data on immune system effects emerges, this group may be extremely important to watch and supplement.
However, do not forget the great sun.
The bottom line is: 1) get outside and play; 2) use sunscreen to prevent burns, not the sun’s beneficial effects; 3) exercise daily; 4) talk to an experienced practitioner regarding your risk; 5) eat a diet based predominantly on plants and limit processed food; 6) love your children.
Dr. Christopher Magryta is a pediatrician with Salisbury Pediatric Associates.