Originally published in the North Lake Tahoe Bonanza (link), October 18, 2010. New research demonstrates the many benefits of vitamin D and this vitamin's role in a remarkable array of health systems.
Both vitamin D3 (produced by skin in response to sunlight) and D2 (from fortified dairy products, fatty fish, eggs, and some plants) are broken down before being whisked off to target organs. Receptors have been found in brain, intestine and colon, prostate, breast, immune system, heart and blood vessels.
Deficiencies are becoming more widespread. There are few dietary sources of vitamin D and despite our intent to eat healthier, the typical American diet is becoming progressively poorer through depletion of the food chain and subsequent processing. Hospitals are now seeing pediatric cases of both obesity and, at the same time rickets, a disease of vitamin D deficiency previously almost eradicated.
We spend less time outside and wear more sunscreen, protecting our skin from cancer and photoaging but decreasing our primary natural supply. Those with more melanin, the skin pigment which darkens our skin, generate less vitamin D. Aging also decreases production — our skin makes less vitamin D just when it offers the greatest benefits.
So what are these benefits?
Bone Health: Given its role in calcium transport, research has focused on supplementation's impact on fractures. Less fractures occur, but only with doses higher than found in most multivitamins — at least 800 IU per day.
Cognition: A recent study revealed groups most deficient in vitamin D demonstrated a six-fold increase in cognitive impairment. Fracture studies show reduced falls with supplementation, likely due to improved coordination and cognitive function.
Immune System: Deficient individuals experience more upper respiratory infections, including influenza. Supplementing vitamin D reduces risk for several autoimmune diseases, including multiple sclerosis, rheumatoid arthritis, lupus and diabetes.
Cardiovascular: The leading cause of morbidity and mortality, patients who are vitamin D deficient exhibit increased stiffening and thickening of the heart and blood vessels, with higher rates of hypertension, heart attacks, strokes and ventricular hypertrophy.
Cancer: Multiple cancers, including colon, prostate and breast are more prevalent when vitamin D levels are low. It is not yet clear if lack of vitamin D is the cause, or rather a marker of poor health, diet or other causative factor.
Pregnancy: New studies show 50 percent less complications, including gestational diabetes, hypertension, preeclampsia and preterm birth when pregnant women received very high levels of supplementation (4,000 IU per day).
So what can you do?
Know your level. Most people need at least 1000 IU per day of vitamin D3 (or 3000 IU of D2, which requires more for the same effect). Many require 4000-5000 IU to achieve recommended levels.
Balance skin health with sunlight's benefit. Getting outside improves mood and fitness in addition to vitamin D production. Consider limited sun exposure without sunscreen (some dermatologists suggest 15 minutes in the morning or late afternoon when burn risk is lower) while continuing sunscreen use on damage-prone face, neck and chest skin and maintaining regular cancer screening.
Eat real food. Wild fatty fish, produce grown on nutrient-rich local soils and a varied diet of minimally processed foods are not only good defense against dietary deficiencies, your taste buds will thank you, too.
—Dr. Rebecca Gelber is an Incline Village resident and graduate of The Johns Hopkins School of Medicine. She is an adjunct professor with the UNR School of Medicine and practices locally at Tahoe Aesthetic and Integrative Medicine. She can be reached at www.tahoemedicalspa.com or 775-298-1750.