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Obesity Conference Draws 200 to Academy to Learn Latest About Research and Treatments for this Epidemic Condition NEW YORK CITY, Dec. 5 - With more than half of all U.S. adults now officially classified as overweight or obese, the nation is facing a fat-related health crisis of unprecedented proportions. Many diseases are more prevalent among the obese, and fat-free foods and weight loss diets are not doing enough to help them permanently shed pounds. About 200 physicians and clinical nutritionists eager to learn more about the latest in obesity research and treatments attended a Dec. 3 conference at the Academy, sponsored by the Academy’s Section on Clinical Nutrition. Speakers explained the differences in effectiveness of low-fat and low-carbohydrate diets, the biology of eating behaviors, the chemical pathways behind weight gain, and more. “Obesity is a pandemic and still spreading,” said keynote speaker Jesse Roth, M.D., Geriatrician-in-Chief at the North Shore-Long Island Jewish Health System and Professor of Medicine at the Albert Einstein College of Medicine. “It accelerates mortality, intensifies many diseases, and spreads unhappiness.” The basic premise behind weight gain is simple: eat more calories than you burn, and you’ll pile on pounds. Someone on a 2,000-calorie-per-day diet who eats an additional 10 calories each day—the equivalent of one Lifesaver—will gain a pound per year if you don’t increase the number of calories you burn. Obesity accelerates the aging process and causes diseases to appear earlier, more often and at greater intensity. Alzheimer’s disease, arthritis, cancer, depression, diabetes, heart disease, liver disease and sleep apnea are among the many complications of obesity. Understanding the neurobiological control of meals is critical to developing effective obesity treatments, said Gary J. Schwartz, Ph.D., of the Department of Psychiatry at Weill Medical College of Cornell University. When a person begins eating a meal, positive feedback signals encourage the consumption of more food. As food accumulates in the gastrointestinal system, there’s a growing negative feeling in the gut that leads us to stop eating. Any disruption to this “gut-brain axis” —either natural or intentional —can cause us to eat more or less. Gastric bypass surgery, for example, increases the potency of negative feedback from the gut and causes us to stop eating sooner. Inadequate levels of the gut-based hormone CCK (commonly known as the “feel full” hormone) can result in overeating, since CCK signals the brain that it is time to stop eating. Researchers have found that certain rats (called obese otsuka rats) overeat every meal by at least 50 percent because they lack CCK sensitivity. A person’s health risks can be partially predicted based on where his or her body stores the most fat, explained Meredith Hawkins, M.D., of the Albert Einstein College of Medicine. Someone with an abdominal fat depot has a greater risk of cardiovascular disease, for example, Hawkins said. That’s because adipose tissue, as abdominal fat is known, secretes cytokines related to heart disease. Women with elevated levels of the cytokine Interleukin-6, produced by abdominal fatty tissue, face heightened risk of cardiovascular disease. Cytokines also lead to the production of C-Reactive Protein, which significantly elevate the risk of heart attack, stroke and other cardiovascular disease when present at high levels. Though both genetic and environmental factors contribute to obesity, weight loss is clearly achievable—though there is not one “best approach” for everyone. Low carbohydrate and low-fat diets are both popular and effective weight loss methods. While neither is the proven winner for long-term results, several studies have shown that low-carb dieters tend to lose more weight in the short term, said CJ Segal-Isaacson, Ed.D., R.D., of the Albert Einstein College of Medicine. A variety of factors may explain this, according to Jeffrey Volek, Ph.D., R.D., of the University of Connecticut. That low-carb dieters eat more protein than carbohydrates gives them a metabolic advantage, since the body uses more energy (burns more calories) to process protein. Low-carb dieters may also wind up eating less because they become bored with the limited variety of foods they are permitted to consume. Concern remains over whether a low-carb, high-fat diet increases heart disease risk, Volek said. The American Heart Association still cautions against very low-carb diets (which allow less than 10 percent of calories from carbohydrates) for that reason. Several researchers are working to obtain objective data on how both diets affect heart disease risk factors over time. Segal-Isaacson is studying the varied effect of low-carb and low-fat diets on cholesterol levels, for example. A recent study led by Joseph T. Hickey, M.D., an internist at Heritage Medical Center in Hilton Head, S.C., actually found that low-carb eating plans decreased dieters’ risk factors for heart disease. Hickey explained that he studied 122 older patients on a low-carb diet for eighteen months and found they experienced a dramatic 82 percent (on average) reduction of small LDL particles, commonly known as “bad” cholesterol. The low-carb diet also led to an increase in large LDL particles, which are less harmful, and in large HDL particles, or “good” cholesterol. “We always thought the Atkins diet would raise your cholesterol,” Hickey said. “Well, guess what: it doesn’t.” Many speakers at the conference concluded that one dietary plan does not fit all, and urged health professionals to be open-minded about trying alternative diets with their patients. Different weight loss approaches may be more or less effective in different people, said Barbara Lowell, R.D., C.D.N., co-chair of the Academy’s Section on Clinical Nutrition. Some people may achieve better results with low-carb diets, while others may see results from a low-fat plan. “I’m not sure that there’s one diet for everybody,” Lowell said. All obese patients and their nutritionists should keep in mind that dramatic weight loss is not the only goal worth striving for, Roth said. Health can be improved substantially, and risk can be lowered, if obese people lost just five to 10 percent of their body weight and exercised moderately. Even a small weight loss, though not cosmetically visible, can help to improve obesity-related medical complications. We gain an average of one pound per year between the ages of 25 and 55, and those pounds really add up to become a health detriment. “All diets can be useful if you adhere to them,” Klein said. “It’s the lack of adherence that causes the problems.” The conference was funded through an unrestricted grant from the Dr. Robert C. Atkins Foundation, founder of the Atkins Diet. The New York Academy of Medicine is a non-profit institution founded in 1847 that is dedicated to enhancing the health of the public through research, education and advocacy, with a particular focus on urban populations, especially the disadvantaged. Contact: |