Calcium’s secret benefit
Last month, I told you how even if you have a family history of colon cancer you could slash your risk by consuming more folic acid. Now, new research is suggesting another nutrient that may play a significant role in preventing colon cancer.
In the March issue of the Journal of the National Cancer Institute, researchers at the Harvard School of Public Health report that calcium intake can influence the risk of certain types of colon cancer. And to reap these benefits, you don’t need to overload on calcium from dietary sources or from supplements – as the study says, “moderate levels” of calcium intake are enough to offer protection.
Calcium intake slashes colon cancer risk by HALF
The Harvard researchers analyzed data on 87,998 women from the Nurse’s Health Study and 47,344 men from the Health Professionals Follow-up Study. Both are huge, long-term cohorts that have generated landmark research over the past several decades. Out of the more than 135,000 eligible participants in the cohorts, there were 626 cases of colon cancer among the women and 399 cases among the men. The researchers then compared data from the participants’ food frequency questionnaires with the incidence of colon cancer.
Colon cancer cases were classified as distal (occurring on the left side, or in the descending colon) or proximal (occurring on the right side, or in the ascending colon). And the researchers found that people who consumed between 701 and 800 mg of calcium each day were half as likely to develop distal colon cancer as those who consumed 500 mg a day of calcium or less. However, no association was seen between calcium intake and proximal colon cancers.
According to conventional thinking, both distal and proximal colon cancers are equally serious and share similar prognoses, although distal cancers are often diagnosed at earlier stages. The researchers aren’t sure why calcium provided a benefit for one and not the other. Previous studies in animals had suggested that calcium may play a role in the development of colon cancer. We know that calcium can bind acids which could otherwise promote cell proliferation in the colon, but previous studies in humans had shown inconsistent results.
Moderate intake enough to provide protection
Another interesting point is that the beneficial calcium intake levels in this study are considerably below standard recommendations; most sources recommend that women and men over 50 get 1,200 mg of calcium each day. And the authors note that “calcium intake beyond moderate levels may not be associated with further risk reduction.”
That means it should be fairly easy to get the benefit of calcium’s cancer protection from your regular diet. And you don’t have to turn to dairy as your only source of dietary calcium. Half a cup of cooked kale contains 100 mg of calcium; half a cup of yellow, green, or wax beans contains 55 mg; a medium orange contains 55 mg; three ounces of salmon contains 80 mg. Of course, if you have trouble getting enough calcium from your diet, calcium supplements are always an option.
In the July 1999 issue of your Members Alert, we told you about AdvaCal, an easily absorbable form of calcium made from oyster shell. In several double-blind placebo controlled trials measuring its potential for fighting osteoporosis, AdvaCal not only stopped bone loss, but actually increased bone density. This issue of your Members Alert isn’t currently posted on the website, but you can learn more about AdvaCal directly from Lane Labs at (800)526-3005.
Whether you get it through dairy, leafy greens, or a capsule, it is clearer than ever that sufficient calcium is critical to good health. Since colon cancer is now the second leading cause of cancer deaths, please feel free to send this important news about how to cut your risk in half to your family and friends.
To Your Good Health,
Jenny Thompson
Health Sciences Institute
Source: Journal of the National Cancer Institute 2002;94:437-446
Copyright 1997-2002 by Institute of Health Sciences, L.L.C.
