The recent WHO report categorizing processed meat as carcinogenic caused a big stir in the media and increased public awareness of the importance of nutrition and lifestyle choices. It is important to keep in mind that over-consumption of any food, especially those with unnatural components, can be detrimental to your body. A balanced diet, including limiting indulgences such as processed meat, is key to maintaining your health.
At the core of overconsumption is an unhealthy lifestyle, which can lead to broader health issues such as obesity. Obesity (having a body mass index or BMI of 30 and above) is a strong risk factor for various types of cancer for both men and women. Obesity also impacts survival rates for those with cancer. According to the American Cancer Society, one of every three cancer deaths in the United States is linked to obesity, poor nutrition and a sedentary lifestyle.
The link between cancer and obesity
Adipose (fat storage) tissue is highly metabolically active, releasing hormones, growth factors and signaling molecules that influence the behavior of other cells in the body, including cancerous ones. These molecules, and those listed below, do not necessarily cause cancer themselves, but rather feed the malignant cells, enabling them to grow and multiply.
Hormones can also have an effect on cancer growth. Estrogen (produced in fat tissues as well as ovaries) and insulin in cases of those with type II diabetes, can result in insulin resistance and lead to an excess of glucose, enabling certain cancers to grow faster. Research has shown that women and men with a high BMI, who often have excess breast tissue and elevated estrogen levels, are at a greater risk for breast cancer.
The proteins, interleukins (overstimulated in obese people) and adipokines (cytokines produced by fat tissue and impacted by weight gain), have also been linked to cancer. The overactivity of C-terminal binding protein (CtBP), triggered by metabolic imbalance such as diabetes and obesity — often caused by elevated carbohydrate intake — has been connected to an increased risk of breast cancer.
What types of cancer have been linked to obesity?
According to the National Cancer Institute, endometrial cancer is the most prevalent, with an estimated 39 percent of cases linked to obesity, followed by esophageal (37 percent), kidney (25 percent), colon (11 percent) and postmenopausal breast cancer (nine percent).
Researchers continue to study molecular pathways looking for links between obesity and cancer risk as well as any genetic variants that could affect the risk factors. Clinical studies are also looking at the possibility that a common diabetes drug, metformin, might help reduce the risk of cancer for people with increased risk.
Reducing the risk of obesity-related cancer
The simplest way to reduce the risk for obesity-related cancer is to lose weight, the hardest for a majority of people. With more than one-third (34.9 percent) of American adults being obese — and another 17 percent of children under 19 also in that weight category — the odds of developing cancer continues to increase.
Here are some strategies to maintain your health:
- Know your BMI. Use the BMI calculator from the National Heart, Lung, and Blood Institute to calculate your number.
- Increase your physical activity level. The CDC recommends 30 minutes a day five days or more a week of moderate-intensity physical activity.
- Eat a healthy diet. The ChooseMyPlate website has a variety of guidelines and tips to promote healthy eating.