The Vitamin D Factory
You need more of this vitamin once you hit your forties. Without enough, everything goes downhill.
Your body is an amazing chemical factory with thousands of specialized subdivisions. For example, it must make vitamin D to thrive. Along with food sources, your body converts sunlight to active vitamin D. It's a ten-step process involving multiple chemical reactions and three organs.
UVB radiation from sunlight is turned into previtamin D3, then cholecalciferol, then 25-hydroxyvitamin D, or calcidiol. The process requires a specialized skin cholesterol, carrier proteins, enzymes, and dedicated receptors.
But like any factory, problems occur. The equipment ages and gets worn; the assembly lines slow or break down. When that happens to vitamin D synthesis, absorption, and metabolism, your body malfunctions – hormone production is compromised, protein synthesis is decreased, the immune system takes a hit, your sex drive plummets, and even your mental health suffers.
Studies show that our vitamin D factories begin to wear out in middle age, even as young as our 40s. We need more vitamin D – or a more bioavailable form (Buy at Amazon) of this vitamin/prohormone – than we did in our 20s, even if we get plenty of sunlight, eat the right foods, and take supplements.
Why Doesn't My Vitamin D Work Anymore?
Several factors contribute to this decline in vitamin D absorption and utilization:
- Reduced Skin Synthesis: Teenaged skin is highly efficient at converting sunlight into active vitamin D. Somewhere in your 30s though, it starts to get less efficient, about the same time you notice fine lines. Skin gets thinner as we age. The thinner the skin the less efficient it gets at producing vitamin D in response to sunlight, especially after 40. Older adults produce 25-50% less vitamin D than younger folks when exposed to the same amount of ultraviolet radiation. And ironically, too much sun quickens the thinning of the skin.
- Decreased Dietary Absorption: The body's ability to absorb vitamin D from food and supplements declines with age. This is due to changes in the gastrointestinal tract, like reduced stomach acid production and enzymes.
- Aging Kidneys: The kidneys play a big role in converting vitamin D into its active form. As kidney function naturally declines with age, this conversion process becomes less efficient.
- Middle-Aged Chubbiness: Vitamin D is stored in fat tissues. The fatter you are, the more vitamin D is sequestered in adipose tissue. This sequestration reduces the amount of vitamin D available in the bloodstream.
What To Do About It
The usual advice of "get more sunlight" doesn't really apply when your favorite song from high school is now classic rock. Your skin doesn't kickstart the vitamin D factory as well as it used to, and getting extra sunlight just leads to extra wrinkles.
Eating more vitamin D-containing foods helps, but remember, absorption declines as you age. Two things, however, make a big impact: losing fat if you need to and supplementing with vitamin D3. But, the post-40 body may require more than a grocery-store vitamin D supplement to ensure absorption.
The solution? Microencapsulated D3 (Buy at Amazon). Microencapsulation greatly improves the bioavailability of vitamin D3 – a much higher proportion is absorbed and utilized by the body. The same delivery system also allows for sustained release of the vitamin, allowing you to maintain steady levels in the bloodstream.
D Fix High Absorption Vitamin D (Buy at Amazon) contains 5000 IU of microencapsulated vitamin D3.
References
- Wortsman J, Matsuoka LY, Chen TC, Lu Z, Holick MF. The New England Journal of Medicine. 2000;342(15):1079-1085.
- Lichtenstein GR, Russell MW, Berardi RR. Digestive Diseases and Sciences. 1994;39(2): 203-207.
- Fliser D, Ritz E. Nephrology Dialysis Transplantation. 1996;11 Suppl 9:2-14.