"Approximately one-third of cancer cases are related to smoking, one-third to poor diet and lack of exercise, and one-third to genetic or other factors," he says. "Most Americans are already aware of the detrimental effects of smoking, but the rate of obesity and poor diet in this country is cause for alarm."

Savaiano, who is chairman of the Food and Nutrition Science Alliance, or FANSA, recently worked with several of the organization's members to review scientific studies on diet and cancer. FANSA is a joint committee of the American Dietetic Association, the American Society for Nutritional Sciences, the American Society for Clinical Nutrition and the Institute of Food Technologists.

The group has issued a statement urging Americans to change their diets to help reduce the number of cancer-related deaths.

Savaiano notes that though some types of cancer are more influenced by diet than others, nutrition and food scientists agree that there are four practical diet-related ways to lower cancer risk:

• Eat plenty of fruits, vegetables, whole grains and legumes in accordance with the U.S. Department of Agriculture's Food Guide Pyramid.

• Avoid empty calories from highly processed foods that are high in fat and/or sugar.

• Choose activities that involve moderate or vigorous exercise.

• Limit or abstain from alcohol.

He says that consumers should not let fear of pesticide residues deter them from eating fruits and vegetables, because the benefits of eating these foods appear to outweigh any potential risk.

Savaiano attributes Americans' difficulty in developing a healthy lifestyle to several factors, including lack of knowledge on how to implement specific actions and a lack of marketing forces aimed at creating consumer demand for a healthy lifestyle.

"Many foods that are widely advertised tend to be high in calories and relatively low in nutrients, while few advertisements appear for less processed foods such as vegetables and fruits or whole grains and beans," he says.

Long workweeks also translate into less time for meal preparation, he says, noting that meals often are purchased as takeout or from fast-food restaurants.

Savaiano says that in order to effect a change, all food, nutrition, fitness, health and government organizations must work together to promote healthy lifestyles.

Note: If no author is given, the source is cited instead.

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