Body Weight and Cancer Risk

Being overweight has been linked to a higher risk of getting 13 different cancers:

• Breast (after menopause).
• Colon & rectum.
• Esophagus.
• Stomach.
• Liver.
• Gall bladder.
• Pancreas.
• Endometrium.
• Ovary.
• Kidney.
• Prostate.
• Thyroid.
• Multiple myeloma.

How does too much body fat raise your risk of cancer?

Extra body fat leads to higher levels of some hormones and proteins that may cause cancer cells to grow. These are insulin, leptin, and estrogen, among others.

• Fat cells can cause chronic inflammation (swelling), which is linked to increased cancer risk.
• Research has also shown that people with extra fat around the waist (the “apple shape”), may be at higher risk because this fat causes even more cell growth, increasing the risk of cancer.

Bodyweight is measured using body mass index or BMI. BMI is based on your height and weight. The BMI chart classifies your body as underweight, healthy, overweight, or obese. This is a good place to start to figure out your body weight and see where you fall on the chart.

A healthy diet, regular physical activity, and keeping a healthy weight have been shown to lower cancer risk. These three things, called the prevention triangle, are important steps in cancer prevention. Not smoking is also important. A few studies have found that losing weight can help lower the risk of weight-related cancers. Studies about weight loss and cancer have been done with those who had bariatric (weight loss) surgery. In a sample of these patients, cancer death rates were lower than people who were obese and did not have surgery.

Losing weight is not easy. It takes a lot of effort to make big lifestyle changes. Seek support from friends, family, your healthcare providers, and weight loss programs. Look into websites or applications (apps) to track progress and motivate you.

Resources to learn more about how diet, physical activity, and weight are related to cancer:

• The “Prevention Triangle” Exercise, Weight Control, and Healthy Diet.
• American Institute for Cancer Research.
• Eat Healthy and Get Active at the American Cancer Society website.
• Dietary Guidelines for Americans, 2020-2025 from the USDA.
• The US Department of Health & Human Services Physical Activity Guidelines for Americans, 2nd edition (2018).
• NIH AARP Diet & Health Study: A study developed at the National Cancer Institute of the National Institutes of Health to improve our understanding of the relationship between diet and health.
• The European Prospective Investigation into Cancer & Nutrition (EPIC): A large study by the International Agency for Research on Cancer investigating the relationships between diet, nutritional status, lifestyle and environmental factors and the incidence of cancer and other chronic diseases.