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Betsy's Article Library Overweight and obese women who took calcium and vitamin D supplements while dieting had improved cholesterol levels, according to results from a new study. Researchers from Laval University, Sainte Foy, Canada, recruited 63 overweight or obese but otherwise healthy women whose diets included less than 800 mg per day of calcium. The recommended daily allowance for calcium in the U.S. is 1,000 mg, and 800 mg for Europe. Scientists placed the women on a 15-week diet plan that allowed 700 fewer calories per day than the women normally consumed. Each woman took a placebo or a tablet that contained 600 mg of elemental calcium and 200 IU of vitamin D, twice per day. Compared to placebo, at the end of the 15-week treatment period, those who had taken calcium and vitamin D had significantly improved high-density lipoprotein (HDL, the "good" cholesterol) compared to total cholesterol and to low-density lipoprotein (LDL, the "bad" cholesterol). Doctors noted that the beneficial changes in the relationship of HDL to total cholesterol, and HDL to LDL did not depend on changes in body fat (fat mass) or waist size. Those who took calcium and vitamin D also had higher absolute levels of HDL, lower absolute levels of LDL, lower levels of total cholesterol, and other blood fats (triacylglycerol, or triglycerides) compared to placebo. The scientists believe that calcium may reduce the amount of fat that passes from the gut to the bloodstream, may improve the ability of the body to burn fat, and may help people feel full (satiety). Reference: American Journal of Clinical Nutrition: January, 2007; Vol. 85, No. 1, 54-9.
 A large, new Chinese study has found that calcium protects against cancer of the colon and rectum (colorectal). The Shanghai Women’s Health Study, from 1997 through 2000, enrolled 73,314 Chinese women aged 40 to 70, average age 55.5, who were living in urban Shanghai. Researchers followed up for an average of 5.7 years and, excluding the first two years of follow up, found that those with the highest amounts of calcium in the diet were 40% less likely to develop colorectal cancer than were those with the lowest dietary calcium. By the end of the follow up period, there were 129 reported cases of colon cancer, and 91 reported cases of rectal cancer. The study is significant because of the large number of participants, and because the Chinese diet typically includes less calcium than does the Western diet. Previous large U.S. studies: the 1991 Women’s Health Initiative with 161,808 women, the 1976 Nurse’s Health Study I with 122,000 women, and the 1989 Nurse’s Health Study II with 125,000 women, did not report any link between calcium and colorectal cancer. , and because the Chinese diet typically includes less calcium than does the Western diet. Previous large U.S. studies: the 1991 Women’s Health Initiative with 161,808 women, the 1976 Nurse’s Health Study I with 122,000 women, and the 1989 Nurse’s Health Study II with 125,000 women, did not report any link between calcium and colorectal cancer.As in those studies, doctors in the Shanghai survey asked participants to fill out a food-frequency questionnaire, covering 77 foods representing 90% of the typical diet. Researchers also calculated the amounts in the diet of vitamins A, B1, B2, B3, C, and E, as well as carotene and fiber, and found no link to risk for colorectal cancer. The scientists concluded that calcium appears to protect against colorectal cancer, even at the relatively low levels in the Chinese diet compared to the Western diet. Colorectal cancer is one of the most curable cancer types, and doctors can diagnose the disease easily and early using a colonoscopy exam. Reference: International Journal of Cancer; 2006, Vol. 119, No. 12, 2938-42. The articles on Betsy's website are reprinted courtesy of Retail Insights, Inc. Copyright 2007. | ||||||
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