Obesity and Cancer

Evidence strongly suggests that obesity is associated with an increased risk for breast, colorectal, endometrial, esophageal, and kidney cancer.  Obesity is also linked with cancers of the cervix, gallbladder, ovary, pancreas, and thyroid.  Multiple myeloma, Hodgkins lymphoma, and aggressive prostate cancer are associated with excess body fat.

In US, more than 66% of the population is considered overweight or obese.  Obesity has tripled since 1992 and projected to continue increasing.

Higher BMI associated with increased risk for:

• Thyroid
• Renal
• Colon
• Adenocarcinoma of the esophagus
• Multiple Myeloma
• Leukemia
• Non-Hodgkins Lymphoma

Men/Higher /BMI

• Rectal
• Malignant Melanoma

Women/Higher BMI:

• Gallbladder
• Pancreas
• Endometrium
• Breast (Postmenopause)

Obesity is also associated with a poorer prognosis in breast, colon, prostate, endometrial, ovarian,

Theories:

• Circulating endogenous hormones such as insulin*, insulin-like growth factors, sex steroids.
• Changes in metabolism of adipokines**
• Localized inflammation
• Oxidative Stress
• Altered Immune Response
• Hypertension
• Lipid Peroxidation

*Chronic hyperinsulinemia is known to reduce circulating levels of insulin-like growth hormone (IGF) binding protein 1 and IGF-binding protein 2 - decreases availability of IGF.  Promotes an environment that favors tumor formation.

**Adiponectin is the most abundant circulating adipokine - inversely correlated with BMI.  Women typically have greater concentrations than men.  Greater concentrations beneficial - anti-inflammatory, antioxidant, antiangiogenic, insulin-sensitizing.






Clinical Nutrition for Oncology Patients, 2010 Jones and Bartlett Publishers