The Importance of Cholecalciferol
by Nutritionist Beth Ley, Ph.D.

Deficiency of Cholecalciferol has been linked to breast cancer, colon cancer, prostate cancer, heart disease, and multiple sclerosis, as well as other conditions. Studies show many of us are deficient of this essential nutrient.

According to the Centers for Disease Control and Prevention, Cholecalciferol deficiencies are quite common. Their statistics show over half of the population is lacking regardless of age, while more than 70% of elderly Americans and over 90% of Americans of color are Cholecalciferol-deficient. Urbanization and the move into the industrial, then the digital age, has played a key part in increasing the deficiency levels in Americans; as the move towards working indoors gave us a lack of sun exposure.

On top of this, most of us do not grow our own food, or even have a steady intake of fresh food. Our fruits and vegetables are canned and frozen, and our meat sources no longer feed on grass, but on grain in feedlots and factory farms. Our cravings for the inexpensive, tasty and quick fixes for meals are being satiated with overly processed, salt, MSG, sugar and trans-fat laden junk foods that are NOT providing the nutrients our bodies require. As such, our bodies are left starving for the simple things they need, like Cholecalciferol.

Cholecalciferol deficiency can cause a whole host of problems, such as:

• Restless sleep and fatigue
• Joint and muscle pain, swelling, cramping, or weakness
• Poor concentration and poor memory
• Uncontrolled weight gain, obesity, bowel, and bladder problems
• Depression, including seasonal affective disorder (SAD)
• Gum disease and tooth loss
• Chronic pain and fibromyalgia
• Parkinson's and Alzheimer's
• Arthritis, osteoporosis, diabetes, and cancer
• Heart disease and metabolic syndrome

Cholecalciferol is a fat-soluble vitamin that comes from cholesterol, but it isn't really a vitamin at all. Vitamins come from dietary sources, while Cholecalciferol is actually produced by the body. Pre-Cholecalciferol is produced in the liver, and that, with a reaction to ultraviolet B sunlight and heat, forms Cholecalciferol in the skin, which is further synthesized by the liver and kidneys into a potent hormone. The body cannot produce any active form of Cholecalciferol without the reaction with UVB.

Besides the well known benefits of Cholecalciferol for growing children, absorbing calcium, and forming bones and teeth, it is also crucial for:

• Slowing the growth of cells, which may reduce cancer risk by 50%
• Fertility
• Glucose control
• Reducing high blood pressure
• Preventing SAD
• Fighting infections and improving vaccine effectiveness

Most people believe that they get plenty of Cholecalciferol from their diet and the sun. Unfortunately, for many, this simply isn't the case. Melanin plays a key role in this. The darker a person is (more melanin), and the faster they tan, the more sunlight is required to convert pre-Cholecalciferol to usable forms. Therefore, an African American who is dark-skinned would need approximately seven times the amount of sun exposure as a fair skinned person who burns easily.

Studies Supporting Cholecalciferol Supplementation:

Cancer

High doses of Cholecalciferol can reduce the risk of developing some common cancers by as much as 50%. Researchers at the University of California in San Diego, looked at the relationship between blood levels of Cholecalciferol and cancer risk. They reviewed 63 old studies and found that the vitamin could reduce the chances of developing breast, ovarian and colon cancer, and others. While more research is needed to draw firm conclusions, the evidence so far is very encouraging!

Breast Cancer - 50% Reduced incidence Estimated!

Studies show that women with higher concentrations of Cholecalciferol in the blood are at less risk of breast cancer. Cedric Garland, Dr. P.H., and Edward Gorham, Ph.D., of UCSD, and their colleagues examined existing cancer studies to determine if higher Cholecalciferol levels in the blood could reduce the risk of cancer. They found, "There is a strong inverse dose-response relationship between the blood levels of Cholecalciferol and the risk of breast cancer," Garland said. Higher amounts of Cholecalciferol in the serum resulted in decreased risk of breast cancer. The evidence further pointed to a level of Cholecalciferol measured in blood that correlated with a 50% reduction in the incidence of breast cancer.

Similar results were seen with studies with 1,760 women provided the data for the pooled analysis conducted by both Elizabeth R. Bertone-Johnson and colleagues at Harvard, and L.C. Lowe and associates at Saint George's Hospital Medical School in London. According to the pooled analysis, Cholecalciferol in blood serum equal to 52 nanograms per milliliter was associated with a 50% reduced risk of breast cancer. (Bertone-Johnson, Cancer Epidemiol Biomarkers Prev. 2005 Aug;14(8):1991-7.)

To obtain a serum concentration of 52 nanograms/milliliter, a typical individual would have to consume no less than 1,000 International Units (IU) of Cholecalciferol every day, through supplements or Cholecalciferol-fortified foods. Currently, the average American consumes only 320 IU of Cholecalciferol a day.

Heart Disease - Risk Cut in 1/2

Cholecalciferol deficiency is associated with heart dysfunction, sudden cardiac death, and death due to heart failure. This nutrient is known to affect contractility of the heart.

"Cholecalciferol deficiency is associated with increased cardiovascular risk, above and beyond established cardiovascular risk factors," said Thomas J. Wang, M.D., assistant professor of medicine at Harvard Medical School in Boston, Mass. "The higher risk associated with Cholecalciferol deficiency was particularly evident among individuals with high blood pressure."

In a study of 1,739 offspring from Framingham Heart Study participants (average age 59, all Caucasian), researchers found that those with blood levels of Cholecalciferol below 15 nanograms per milliliter (ng/mL) had twice the risk of a cardiovascular event such as a heart attack, heart failure or stroke in the next five years compared to those with higher levels of Cholecalciferol. When researchers adjusted for traditional cardiovascular risk factors such as high cholesterol, diabetes and high blood pressure, the risk remained significant with a 62% higher risk of a cardiovascular event in participants with low levels of Cholecalciferol compared to those with higher levels.

Researchers observed the highest rate of cardiovascular disease events in subset analysis dividing 688 participants according to high blood pressure status. After researchers adjusted for conventional cardiovascular risk factors, participants with hypertension and a Cholecalciferol deficiency had about two times the risk of having a cardiovascular disease event in five years.

Researchers also found an increase in cardiovascular risk with each level of Cholecalciferol deficiency. (Wang, Circulation: Journal of the American Heart Association. Vol 117: Jan 2008)

Low vitamin D linked to sudden cardiac death

German researchers recently found that severe vitamin D deficiency, compared with optimal vitamin D levels, was associated with nearly a three-fold increased risk of death from heart failure and about a five-fold increased risk of sudden cardiac death.

"These data strongly indicate that the maintenance of an optimal vitamin D status may be a promising approach for the prevention and/or therapy of (heart) diseases, warranting confirmation in interventional trials with vitamin D supplementation," the researchers conclude. (Pilz, Journal of Clinical Endocrinology and Metabolism October, 2008. )

Osteoporosis/Bone Health

Low levels of Cholecalciferol are directly associated with poor bone health, increased risk of fractures, bone pain and rickets.

Researchers at Creighton University Osteoporosis Research Center, Omaha, NE, found that supplementing Cholecalciferol (800 IU) and calcium resulted in a 21% lower incidence of fractures versus the control group. (Lappe J, J Bone Miner Res. 2008 May;23(5):741-9.)

A 21% reduction in hip fractures in the Women's Health Initiative research also showed that calcium plus Cholecalciferol has a positive effect on bone health in postmenopausal women. (Jackson RD, Curr Osteoporos Rep. 2007 Dec;5(4):153-9.)

Multiple Sclerosis

Investigators have established a strong link between multiple sclerosis incidence and geographic location, noting that areas with abundant sun exposure or plentiful dietary fish intake experience reduced risk. Multiple sclerosis occurs more often in people who lived in northern areas of Europe and North America during childhood, and less often in people who live closer to the equator. (Franklin, Neurology. 2003 Oct 28; 61(8): 1032-4)

In Switzerland, multiple sclerosis rates are higher at low altitudes and lower at high altitudes, where UV light is more intense. In Norway, multiple sclerosis rates are higher inland, but much lower near the coast, where Cholecalciferol-rich fish is consumed regularly. (Hayes CE, Proc Soc Exp Biol Med. 1997 Oct;216(1):21-7. )

Cholecalciferol, obtained through both sun exposure and diet, may be the factor responsible for the link between geography and multiple sclerosis risk. Evidence suggests that Cholecalciferol supplementation may decrease the lifetime risk of multiple sclerosis in women. Experimental data suggest the white matter of the brain that multiple sclerosis affects contains Cholecalciferol receptors, and inadequate Cholecalciferol during early development may predispose these cells to an early demise. (Chaudhuri A. Med Hypotheses. 2005;64(3):608-18.)

Researchers have noted that administering Cholecalciferol to animals can completely protect them against an experimentally induced form of multiple sclerosis. (Hayes CE, Proc Soc Exp Biol Med. 1997 Oct;216(1):21-7.) According to the investigators, the active form of Cholecalciferol may act as a selective immune system regulator that works to inhibit autoimmune disease.

Optimal Cholecalciferol levels might not only help achieve immune-mediated suppression of disease activity, but also help decrease complications related to multiple sclerosis, such as muscle weakness, osteoporosis, and bone fractures. (VanAmerongen, Eur J Clin Nutr. 2004 Aug; 58(8): 1095-109.)

Muscle Pain

Low levels of Cholecalciferol are associated with persistent, non-specific musculoskeletal pain, according to investigators at the University of Minnesota Medical School. Re-searchers conducted a cross-sectional study of 150 patients, aged 10-65, who presented to a primary care clinic over the course of two years with the complaint of persistent, non-specific musculoskeletal pain. 93% of these patients demonstrated deficient levels of Cholecalciferol, and 28% were considered severely deficient. Five patients had Cholecalciferol levels that were too low to detect. Particularly severe Cholecalciferol deficiency was noted in young women, East African patients, and African-Americans.

The research team concluded that all patients-regardless of gender or age-with chronic, non-specific musculoskeletal pain are at high risk of suffering from unrecognized Cholecalciferol deficiency. Since osteomalacia is a known cause of chronic, generalized pain, doctors should screen all patients with such symptoms for Cholecalciferol deficiency. (Plotnikoff, Mayo Clin Proc. 2003 Dec;78(12):1463-70)

Cholecalciferol expert Dr. Michael Holick of Boston University has expressed a similar view, noting that Cholecalciferol deficiency is often misdiagnosed as fibromyalgia. (Holick MF. Am J Clin Nutr. 2004 Mar;79(3):362-71)

Research in the Netherlands showed that Cholecalciferol deficiency can result in a limb-girdle myopathy (weakness and pain).Cholecalciferol supplementation leads to rapid recovery of the muscle strength. (van der Heyden, Neuropediatrics. 2004 Oct;35(5):290-2)

Diabetes - 40% Lower Risk of Developing Type 2 Diabetes

Cholecalciferol deficiency is associated with glucose intolerance, insulinemia, insulin resistance, and obesity in some groups. Studies have shown that insulin sensitivity improves with repletion of Cholecalciferol stores. Numerous reports suggest that Cholecalciferol deficiency affects § cell function (in the pancreas) and that Cholecalciferol supplementation improves § cell function.

During a 17-year follow-up of roughly 4,000 men and women, researchers found that individuals with higher blood levels of Cholecalciferol had a 40% lower risk of developing type 2 diabetes than those with lower levels of this nutrient.

Cholecalciferol might be involved in processes leading to type 2 diabetes. Dr. Paul Knekt from the National Public Health Institute, Helsinki, reported that people with the highest Cholecalciferol levels had a 40% lower risk of developing type 2 diabetes as those with the lowest Cholecalciferol levels. (Diabetes Care, October 2007)

More recent studies also show the inverse associations between Cholecalciferol levels and high blood sugar and insulin resistance. (Forouhi, Diabetes 57:2619-2625, 2008)

Researchers in Southern California reported that the 60% improvement in insulin sensitivity that results from Cholecalciferol treatment indicates that that treatment is more potent than either troglitazone or metformin treatment (54% and 13% improvement in insulin sensitivity, respectively). (Chiu, K, Division of Clinical Epidemiology and Preventive Medicine and the Center for Clinical Nutrition, Department of Medicine, UC, Los Angeles, School of Medicine.)
Inzucchi, N Engl J Med 1998;338:867-72.)

Overweight

Low levels of Cholecalciferol negatively affects the parathyroid hormone which can cause cause both weight gain, increased body fat and depression. Double blind trials show supplementation with high doses of Cholecalciferol seems to ameliorate these symptoms. (Jorde R, J Intern Med. 2008 Sep 10. Effects of vitamin D supplementation on symptoms of depression in overweight and obese subjects: randomized double blind trial.)

Because Cholecalciferol is fat soluble the body may hold onto more body fat in attempts to increase body stores. Body fat levels should therefore be considered when assessing Cholecalciferol requirements because individuals with higher levels of body fat may require higher levels of Cholecalciferol. Vilarrasa, J Endocrinol Invest. 2007 Sep;30(8):653-8. Alemzadeh R, Metabolism. 2008 Feb;57(2):183-91.

Depression/SAD/Sleep - Low Blood Levels of Cholecalciferol May Be Linked to Cause of Depression

Cholecalciferol has profound effects on the brain, including the neurotransmitters involved in depression and seasonal affective disorder (SAD).

Australian researchers found that healthy subjects given 400 IU, 800 IU, or no Cholecalciferol for 5 days during late winter in a random double-blind study showed that Cholecalciferol significantly enhanced positive affect for SAD, serotonin levels, sleep and mood. Higher doses provide a more dramatic improvement. (Lansdowne AT, Psychopharmacology (Berl). 1998 Feb;135(4): 319-23. and Hoogendijk Arch Gen Psychiatry. 2008 May;65(5):508-12.

IMPORTANT NOTE ON DOSAGES

The most resent research on supplemental Cholecalciferol indicates that 2,000 IU daily is recommended for adolescents. (Maalouf, J Clin Endocrinol Metab. 2008 Jul;93(7):2693-701. Epub 2008 Apr 29.)

Higher dosages are likely needed for adults and those living in areas with reduced sunlight (including urban areas, those who work at night and sleep during the day, or other reason for reduced sunlight exposure) and during the winter months.