A fantastic hormone is working in your body right now. It has been called a master hormone, and it helps regulate blood pressure, bone density, mood and behavior, muscle strength, hair growth, immune function, and programmed cell death. This process of programmed cell death is called apoptosis, and it is important in stopping damaged or cancerous cells from reproducing.
What could it be? Growth hormone? Testosterone? Insulin?
None of the above! In fact, medicine was ignorant of its multiple functions for so long, that it was named a vitamin, because just a little bit of it prevents rickets. Still give up? It’s vitamin D!
Whereas even a few years ago, scientists thought this amazing vitamin only controlled bone health, we now know that there are vitamin D receptors on almost every cell in the body.
Humans obtain vitamin D by conversion of substances in the skin after exposure to UVB, light from the sun. We can make up to 50,000 IU of vitamin D in our skin in one day, although 20,000 IU is much more common. As the amount in our skin increases, the skin production diminishes, keeping the supply steady—assuming we get a lot of sunshine. Compared to the paltry amount in foods (cod liver oil contains 400 IU, and fortified milk contains only 100 IU—just enough to prevent rickets), our skin was clearly intended to be our major source of vitamin D. But there are several problems with obtaining your vitamin D only from the sun, especially in the Western world.
The farther north we go, the less vitamin D we can make from our skin. Experts tell us that, in the winter, it is impossible for those who live above the 37th parallel to get enough vitamin D from sunlight. This represents a line starting in Santa Cruz, just south of San Francisco, California, continuing eastward at the northern border of Arizona, New Mexico, Oklahoma, Arkansas, Tennessee, and North Carolina, and ending at the coast. The majority of Americans would be vitamin D deficient in winter even if they wore no clothes and stayed in the sun all day long!
Even in the summer, there are many factors fighting our vitamin D production. Given the concerns over skin cancer and aging, many people use sun block on a daily basis. Sun block even appears in make-up and lotions. We spend most of our time indoors where window glass blocks from our skin the UVB light necessary for the production. Darkly pigmented skin functions as natural sun block, so it is estimated that dark skin requires 5 to 6 times longer to make the same amount of vitamin D as a fair or light skin. The skin of the elderly is less efficient at conversion, and obese people also are at high risk of vitamin D deficiency.
So living in the South, in the summer, we all should have plenty of vitamin D, right? Wrong again. Health professionals in the sunny South have been checking vitamin D levels, and despite well-tanned skin, normal vitamin D levels are rare, even in late summer, when levels should be highest.
So how should we get our vitamin D? And what kind is best? Supplementing vitamin D, specifically D3, is necessary for most people in industrialized nations. Vitamin D3 is also called cholecalciferol, and while the recommended daily allowance of up to 600 IU is only enough to prevent rickets, experts are now calling for much higher amounts (up to 5,000 IU) to reap all the benefits of this remarkable hormone. Vitamin D3 can be extracted from wool in an animal-friendly way, just as sheep are shorn without harm so that the wool can be used for clothing. Acquiring vitamin D from wool actually mimics what animals do when they lick their fur to obtain vitamin D.
Vitamin D2, also called ergocalciferol, is made from irradiated mushrooms. This substance has a very weak vitamin D effect and a very high side-effect profile. Although this is probably the kind of vitamin D your doctor would prescribe, his decision is based upon pharmaceutical industry marketing and not concern for what is healthiest or most natural. I would never recommend vitamin D2.
Vitamin D helps promote bone health, cardiovascular health, emotional health, strength, hair growth, immune function, and normal cell life span. So take at least 5,000 IU daily to ensure the best health you can have!
