Study links obesity with Increased risk for six cancers

Super-size meals, lack of exercise and obesity can dramatically increase the risk of a variety of common cancers, a landmark study by the American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF) has found.

The new study released Wednesday says excess body fat can cause six different types of common cancers, including those affecting the colon, kidneys, pancreas, esophagus, uterus and breasts in post menopausal women.

The WCRF/ AICR report, titled “Food, Nutrition, Physical Activity and the Prevention of Cancer: a Global Perspective”, is based on an in-depth analysis of 7,000 cancer studies from around the world dating back to the 1960s.

The report also includes recommendations from a panel of 21 world-renowned medical experts, who worked for five years to analyze the studies for the comprehensive report, and concluded that body fat and obesity are far more closely associated with cancer than previously thought.

"What's new about this report is that a panel of distinguished scientists from around that world reviewed findings from multiple studies, and when we added them all together we found that excess body fat increases risk of developing cancer," said Dr. Steven Zeisel, an expert on the panel who is also a director of the Nutrition Research Institute at the University of North Carolina.

An advice for people to keep their body weight down throughout their life is at the top of the 10 recommendations for a healthier life in the report, followed by alcohol, exercise and meat consumption. Researchers say they have found convincing evidence that excess body fat as well as consumption of alcohol, red meat and processed meats like bacon can cause a range of common cancers, including the breast, bowel and pancreas cancers.

"The most striking thing to emerge from the report is the importance of overweight and obesity," said Sir Michael Marmot, professor of epidemiology and public health at University College London and head of the medical experts’ panel.

American Obesity Association (AOA) has described the obesity on its Website as a complex, multi-factorial chronic disease involving environmental (social and cultural), genetic, physiologic, metabolic, behavioral and psychological components. It is the second leading cause of preventable death in the U.S.

Obesity is normally measured by body mass index (BMI) that divides the weight by the square of the height. A person is classified as ‘obese’ if his or her body mass index (BMI) is 30 or over. BMI is a simple and frequently used method for estimating body fat:

A BMI less than 18.5 is ‘underweight’
A BMI of 18.5 - 24.9 is ‘normal weight’
A BMI of 25.0 - 29.9 is ‘overweight’
A BMI of 30.0 - 39.9 is ‘obese’
A BMI of 40.0 or higher is ‘severely (or morbidly) obese’.

The WCRF recommends a BMI at the lower end of the healthy range, which is 18.5 to 24.9 (Normal Weight)

The sequence wise top 10 recommended ways to help avoid cancer are: Stay as slim as possible; Take half an hour's vigorous exercise a day; Avoid sugary drinks and fast food; Eat at least five portions of fruit and vegetables every day and cereals/grains/pulses with every meal; Eat no more than 500g of red meat a week and no processed meat; No more than one drink a day for a woman and two for a man; No more than 6g a day of salt; Dietary supplements (vitamin and mineral pills) not recommended; Breastfeed exclusively for six months; Cancer survivors also to follow these recommendations.

Researchers say these recommendations, if followed properly by the people, could definitely help them avoid the risk of developing different types of cancers.

Approximately 127 million adults in the United States are overweight, 60 million obese, and 9 million severely obese.