University of South Florida researcher Barbara Hansen, PhD, says long-term studies show that lifetime calorie restraint to prevent obesity is the most powerful way to reduce age-related health problems such as high blood pressure, high triglycerides and the progression to diabetes.

Dr. Hansen says that the price of leanness is eternal vigilance and losing and keeping off weight requires a lifelong effort.

That she says amounts to maintaining a constant, realistic balance between total calories consumed and total calories expended.

Dr. Hansen is a physiologist and psychologist specializing in obesity, diabetes and their age-related health complications.

She is a professor of medicine and pediatrics, and directs the USF Health ™s Center for Pre-clinical Research, which combines obesity, diabetes and aging research, and the Diabetes Complications Prevention Center.

In her latest studies with rhesus monkeys she has shown that lifetime calorie restraint to prevent obesity is the most powerful way to reduce age-related health problems such as high blood pressure and high triglycerides and to prevent or delay the progression of insulin resistance toward diabetes.

The monkeys whose food intake was maintained in amounts to assure a constant healthy body weight were not only healthier, but they lived longer than their counterparts who ate as much as they wanted.

Hansen says the studies have unequivocally demonstrated that 'if you prevent excess fat deposits in the body through excess calorie restraint, you will improve health and postpone death'.

Hansen says scientific evidence does not support assertions that the epidemic of obesity is the fault of the obese themselves or a "toxic" environment that seduces people with super-sized menus and convenience food at every corner.

She says an approach that places the 'blame on the patient' is both unfair and inappropriate, as scientists are not clear on the complex interaction of genetic and environmental factors that predispose some individuals to obesity while others seem to eat to their heart ™s content without packing on the pounds.

Dr. Hansen considers "single cause" hypotheses such as diet composition, inactivity and obesity genes alone as too simplistic, and believes obesity is a continuum that develops early or late, quickly or slowly, along with 'a heavy dose of genetic predisposition'.

Many studies support the concept that each person has an age-related "set" point for weight somehow regulated by physiology and genetics.

Dr. Hansen says this may help explain why more than 95 percent of dieters who shed 35 extra pounds or more eventually regain the weight, which basically means that while your weight may fluctuate throughout life, your body ™s natural tendency is to return to its individually programmed body composition.

Dr. Hansen ™s team is working to understand the underlying mechanisms of obesity that might lead to new drugs that more specifically target centers in the brain, liver and muscles that regulate weight.

These include compounds, known as mimetic agents, capable of mimicking the benefits of calorie restriction without leaving a person feeling constantly hungry.

For those who are not clinically obese, but are battling the bulge as they approach middle age and beyond, Dr. Hansen suggests setting realistic goals.

She recommends the bathroom scale model of weight loss, where when you see your weight creeping up, you cut back on your portions.

A 10-percent daily reduction in the total calories consumed may produce a small, but at least sustainable, weight loss, and even a modest approach to calorie restraint can have positive health benefits.