As public health experts calculate the number of overweight or obese people in America at 45 million, researchers are delving into the relationship between carrying added weight, genetics and coronary heart disease. Jose Ordovas, PhD, a professor at the Friedman School of Nutrition Science and Policy, and his colleagues found that men carrying a certain gene, called APOE 4, who were also obese or overweight, were in a "double bind." They were more likely to be insulin resistant, a condition that which makes it less likely that their bodies will burn excess fat. Insulin resistance makes active muscle cells unable to take up glucose easily, therefore the blood insulin and glucose levels are higher, inhibiting fat cells from giving up energy stores. Obese individuals have an increased risk for insulin resistance. In simple terms, "their genes were against them once they put on extra weight," explained Ordovas.
In a recent study published in the journal Obesity Research, Ordovas and his colleagues at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts, examined both obese and non-obese men who were divided into three groups, each of which had a different form of the gene Apolipoprotein A (APOE). The three forms of the gene are APOE2, APOE3, and APOE4. APOE is known to regulate cholesterol levels in the blood. The researchers found that men who were of a normal weight all had glucose and insulin levels lower than those of the obese men, regardless of what gene they carried.
Interestingly, obese men with the APOE4 had higher levels of insulin and glucose in their blood than those with normal weight and those who were obese and did not carry the gene APOE4. Therefore, Ordovas and his colleagues concluded that men who carry APOE4 and who are obese are at an increased risk for coronary heart disease, while normal weight men with APOE4 are not
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Contact: Randi Konikoff Beranbaum
randi.beranbaum@tufts.edu
617-636-3736
Tufts University
2-Feb-2004