Can sugar contribute to obesity? Yes.
Can a person eat a lot of sugar and stay slim? Also if.
Many skinny people eat a diet high in refined sugar. Think of all the teenagers who live on soda and fast food. Logically, therefore, sugar is not the only cause of obesity. Of my four children, my son, who never has to worry about his weight, eats more sugar than his brothers, but he stays slim without trying.
There is no doubt that eating more calories than the body consumes leads to obesity. But does the body care if the calories come from sugar or from a healthy balance of fruits and vegetables, meat and potatoes?
At least in many cases, it seems that the answer is no. When patients are admitted to the hospital, they are commonly given intravenous fluids, which are primarily sugar water. Many of these patients lose weight, despite taking in most of their calories as glucose. Cancer patients and other seriously ill people survive on tube feeding alone for months or years. Many of these patients lose weight, despite the high carbohydrate content of the liquid diet. The total calories ingested are simply not enough to meet the needs of the body. The body feeds on itself to compensate for the improper diet and the results of weight loss.
On the other hand, patients who are already overweight or obese often develop cravings for sugar or simple carbohydrates and find that these foods tend to maintain or worsen the overweight condition.
Stays here? Do doctors and scientists understand what is happening?
A few years ago they thought they had the answer. The discovery of leptin deficiency in massively obese mice led scientists to believe that they also held the answer for overweight humans. Leptin tends to inhibit appetite. Lack of this hormone causes mice (and people) to eat voraciously. However, it turns out that most overweight people have more leptin than leaner people. The biological system that controls appetite and weight turns out to be much more complicated than previously thought.
Scientists discovered that certain humans have the mutation that leads to leptin deficiency and obesity at a young age. Treating these children with leptin helps reduce their body weight considerably.
But what about the middle-aged adult who has seen the spare tire inflate over the years? Currently we don’t have a good answer except to eat less and exercise more. Avoiding sugar isn’t a bad idea: It’s so hard to limit your intake to a reasonable amount that total abstinence may be an easier answer. But other simple carbohydrates can be just as bad for your body: white bread, white rice, white potatoes, breakfast cereals, and pasta.
The healthiest diet is one that consists primarily of vegetables and fruits, yet many find this unsatisfying. No matter what scientists discover, a pill may not be the answer for modern man. We simply need to exercise more and eat healthier. The very thought makes me hungry for a piece of cake. What is a person to do? I’m pretty sure if we had to grow our own food we’d all be skinnier, I know I would be. Can I use my teenage children as an excuse for now?
Copyright 2010 Cynthia J. Koelker, MD