The infiltration of the liver by fat is increasingly being recognized as one of the potential dangers of too much weight, says Judith Wylie-Rosett, who holds a doctorate in education and is professor and head of behavioral and nutritional research at the Albert Einstein College of Medicine in New York.
Just like force-fed geese develop fatty livers that are used to make foie gras, excess calories may lead to fat infiltration of the human liver, says Wylie-Rosett, who is a coauthor of the second study in the journal.
“We don’t yet know what the longer term risks are [of excess fat in the liver], but we assume that it may then lead to scarring, and what we are now talking about is nonalcoholic liver disease,” says Wylie-Rosett. “It’s an area of tremendous concern particularly as younger people are becoming heavier and heavier and appear to be getting some of these fatty infiltrations in the liver.”
In the second study, Rachel Wildman, PhD; Wylie-Rosett; and other colleagues analyzed U.S. survey data from 5,440 people. They found a cluster of high-risk symptoms—elevated blood pressure, triglycerides, and blood glucose, among other problems—in 24% of normal-weight people, 49% of the overweight, and 68% of the obese.
“Just because you are lean it doesn’t mean you don’t have cardiometabolic risk,” she says. “We’ve tended to think that weight is a proxy for health but it may be more complicated than that. If you are obese there are still things you can do to be healthy and we need to think about where you stand on the cardiometabolic risk continuum.“
How can you tell if you’re at risk?
• Do you have an apple- or pear-shaped body? Many studies have suggested that excess weight around your gut is more dangerous than weight around the hips and thighs. Belly fat pads organs, and can increase your risk of diabetes compared to other types of fat.
• What is your age and ethnicity? In studies, the odds of being in a high-risk category increased with age, regardless of body size. And in obese people, African Americans were at a lower risk of having metabolic risk factors than white people of the same age and body size.
• Check your lifestyle. People who don’t smoke and who exercise, even if they are obese, are less likely to be in the high-risk category. Smoking seems to encourage fat to cluster in the gut area, says Wylie-Rosett, and exercise protects you, regardless of body size.
• Visit your doctor. Dr. Landsberg says most doctors will check your body mass index, a measure of weight and height, but abdominal circumference is an important indicator of risk too. You won’t be getting a liver scan for fat content anytime soon (too pricey and of uncertain value), but doctors sometimes check for elevated liver enzymes, a sign of liver function. Standard tests for high blood pressure, lipid levels, and increasingly, blood glucose, will help determine if you’re at risk for heart disease and diabetes, regardless of weight.
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