According to a recent Gallup poll, most Americans don't realize the extent to which obesity is linked to medical problems. While the links are clear, what researchers don't know is whether these health problems are caused by the excess weight or an unhealthy lifestyle.

While the Gallup poll found that most of those surveyed knew heart disease was a health problem related to obesity, only four percent knew that weight was connected to diabetes, and just five percent knew of weight's associations with respiratory problems and cancer.

Even though certain forms of heart disease are far more common among people who are overweight, because risk varies greatly depending on where body fat is distributed, researchers remain divided over how much that link has to do with weight itself. Questions also remain about how much heart disease is caused by obesity, and how much can be attributed to unhealthy lifestyle habits such as a sedentary lifestyle and a high-fat diet.

Overweight men are at greater risk than their thinner counterparts for cancers of the colon and prostate, while overweight women have a greater chance of developing cancers of the uterus and ovaries, and post-menopausal breast cancer. This increase in risk could be the result of biological factors, such as the changes in hormone levels resulting from obesity, but other factors such as lack of exercise, and high-fat diets low in fiber, fruits, and vegetables have also been directly linked with these cancers. It could be that the same habits cause both weight gain and increased cancer risk.

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Obesity is most likely the direct cause of health problems resulting from excess weight's affect on normal body functions. For example, being significantly overweight (not just an extra 10 pounds) causes more wear on the spine, hips and knees, thus worsening development of osteoarthritis in these areas. Some types of breathing problems are made worse by obesity because of the increased demand on the lungs.

Does it really matter whether the reason behind obesity's link to health problems is a result of the weight itself or the lifestyle habits that caused it? Yes, because the answer determines how to best approach the problem.

By focusing on weight alone, a person will be more likely to give up a healthy diet and exercise program if the numbers on the scale fail to decrease significantly. However, even without weight loss, regular activity can bring about a reduction in high blood pressure, improved blood sugar control and a stronger heart. Similarly, a healthy diet may not result in a large weight loss but studies have demonstrated lower cancer risk results when we eat according to dietary guidelines provided by the American Institute for Cancer Research and other health organizations: an abundance of a wide variety of vegetables and fruit, a large number of whole grains and lean sources of protein.

Karen Collins, M.S., R.D.,C.D.N.
AICR