I recently read an informative article on vitamin D, written by Dr. Phil Maffetone. In it, he states that more and more research indicates that vitamin D via the sun, or the lack of it, has consequences on optimum health (I have blogged on this topic several times in the past). This includes preventing many types of cancers, immune system function, and muscle
and bone health. The sun is our primary source of vitamin D, and most people are surprised to learn that many Arizonans may be lacking in it. We all know the dangers of too much sun, but the problem of not enough has not been broadcast loudly enough.
Vitamin D is produced in our body through the sun’s exposure to cholesterol, with the liver and the kidneys playing important regulatory roles. Without the sun, our body’s vitamin D content can fall far below acceptable levels. The problem is compounded by dermatologists’ screaming for people to use sun block anytime you go outside, and spf’s now seem to have ratings near 100! Key factors for not getting enough vitamin D:
- using sunscreen that blocks UVB waves
- wearing protective clothing
- going out early and late in the day when sun exposure is greatly reduced
Proper fat metabolism is necessary for vitamin D production, and those with diabetes type-2 may have more of an issue getting enough rays.
In addition to vitamin D, the sun also has positive effects on the brain-just seeing the sun (not staring into it) helps the brain work better. The human eye has photosensitive cells in its retina, with connections directly to the pituitary gland in the brain. A study in the British Journal of Opthalmology states that “these photoreceptors plat a vital role in human physiology and health.”
Photosensitive cells in the eye are also directly affect the brain’s hypothalamus, which controls our body’s circadian rhythm, which regulates hormonal regulation, sleep cycles, reaction time and behavior..
The brain’s pineal gland also benefits from the sun’s stimulation. The pineal produces melatonin, and important hormone made during dark hours that protects our skin, is a powerful antioxidant, and is important for proper sleep and intestinal function. It can also fight depression.
Exposure to morning sunlight helps raise body temperature to normal after a nights sleep, and revs up brain activities including increased alertness and better cognition, helping mood and vitality.
Measuring your vitamin D levels requires a simple blood test, although some home test kits that use a finger prick are also accurate and less expensive (see www.vitaminDcouncil.org).
Stay well, John R Blilie, M.S.