Vitamin D May Prevent Breast Cancer

There are two new reports by cancer prevention specialists at Moores Cancer Center, Univsrsity of California, suggest that vitamin D in new prescriptions may prevent up to one half of all cases of breast cancer.
The study is published online in the current issue of The Journal of Steroid Biochemistry and Molecular Biology. It pooled data from two earlier studies by the Harvard Nurses Health Study and the St. George’s Hospital Study that alleged that people with the highest levels of 25-hydroxyvitamin D, 25(OH)D, had the lowest incidences of breast cancer.

The research was based on 1,760 cases of individuals in the two studies and divided them into five equal groups, from the lowest 25(OH)D at less than 13 nanograms per milliliter, to the highest group with 52 nanograms per milliliter.
"The data were very clear, showing that individuals in the group with the lowest blood levels had the highest rates of breast cancer, and the breast cancer rates dropped as the blood levels of 25-hydroxyvitamin D increased," said study co-author Cedric Garland, Dr.P.H. "The serum level associated with a 50 percent reduction in risk could be maintained by taking 2,000 international units of vitamin D3 daily plus, when the weather permits, spending 10 to 15 minutes a day in the sun."

However, women are warned not to run out and start supplementing their diet. There may be other factors that were overlooked in these studies. While the reports are valid, and the research solid, they only represent 1,760 people out of the entire population.
"Meta-analysis is an important tool for revealing trends that may not be apparent in a single study," said co-author Sharif B. Mohr, M.P.H. "Pooling of independent but similar studies increases precision, and therefore the confidence level of the findings."

The authors recommend further research to study individuals for the effect of vitamin D from sunlight, diet and supplements on the risk of cancer.
The dose-response data on 1,448 people in the study were put into order by serum 25(OH)D level and then divided into five equal groups, from the lowest blood levels to the highest.

Co-author Edward D. Gorham, Ph.D said: "We project a two-thirds reduction in incidence with serum levels of 46ng/ml, which corresponds to a daily intake of 2,000 IU of vitamin D3. This would be best achieved with a combination of diet, supplements and 10 to 15 minutes per day in the sun."

Vitamin D3 is available through diet, supplements and exposure to sunlight, or ultraviolet B (UVB) as long as the skin does not tan or burn. In a white woman, it will only take 10 minutes at noontime on a clear day, with 50 per cent skin exposure, to absorb adequate vitamin D. Darker skin will require up to 25 minutes.

It is important to eat a balanced diet. Vitamin D is linked to Calcium absorption, so overdosing on one will throw out the balance and may result in a depletion of one vitamin.
The reports continued and measured Vitamin D’s ability to prevent colorectal cancer and found similar results.

Dieters Need More Calcium

Women on diets need more calcium than normal to avoid bone loss, say Rutgers University researchers.
Studies showed a weight loss diet of 1.5 pounds a week for 6 weeks cuts absorption of calcium. In 57 postmenopausal dieters it was discovered that those women who took 1,800 mg of calcium a day absorbed 78 percent more calcium than those who took only 1,000 mg a day. To prevent bone loss, women dieting after menopause should get 1,700 mg of calcium a day, the experts say.

For people on low-fat, high fiber diets calcium requirements are also higher. Studies show that 19 percent less calcium is absorbed. It is theorized that the healthier diet moves food faster through the gastrointestinal tract.
While it is common knowledge that calcium is necessary for bone-growth research shows that calcium also fights fat absorption. Studies reveal that calcium blocks fat storage in fat cells. A minimum of 1,000 mg. of calcium daily improves total cholesterol and good HDL, but lowers bad LDL.

Despite the publicity of the importance of calcium for healthy bones research shows that consumption has gone down over the past 30 years.
Experts recommend 1,000 mg of calcium and 400 IU of vitamin D daily for people under 50, and 1,500 mg of calcium and 800 IU of vitamin D for those over 50. The safe upper limit for calcium intake has been set at 2,500 mg a day. Experts think going above that on a daily basis may invite kidney stone formation.

Once started, never stop taking calcium/vitamin D supplements daily. USDA researchers found that after a 3- year study over one-third of participants stopped taking the supplements. Within one year women lost all bone-density gains and men lost their gains in two years.
For those who are lactose intolerant calcium and vitamin D supplementation is even more important because it will be difficult to get the daily requirement through diet alone.
For those allergic to cow's milk. Drink enough soy milk to give you 500 mg of calcium per glass as compared to 300 mg in cows milk. Studies at Creighton University in Omaha, NE, showed that 25 percent less calcium is absorbed from soy milk as cows milk.