For postmenopausal women who are overweight, it makes sense that losing weight could reduce their risk of breast cancer because being overweight or obese increases the risk. But when overweight women are working to shed pounds, is it primarily exercise or cutting calories that makes more of a difference in lowering the risk?
Both, suggests a new study, with weight loss fueled primarily by exercise possibly leading to even more benefits – at least in the short-term for certain markers of breast cancer.
The study is one of the few randomized controlled trials that focuses on teasing apart the effect of diet versus exercise on breast cancer risk. It was published this week in Cancer Epidemiology, Biomarkers & Prevention.
The new Dietary Guidelines for Americans are out and they take a step in the right direction to help you make choices to lower your risk for cancer. Two key pieces of advice–eat a healthy diet that includes plenty of plant foods and keep sugary foods and drinks to a minimum. And that could mean fewer cases of cancer associated with poor diet and obesity.
You can put these into practice with our New American Plate model – filling at least 2/3 of your plate with vegetables, legumes, whole grains and fruit, and 1/3 or less with fish, poultry, meat and dairy.
The guidelines also recommend keeping your added sugar to 10 percent or less of your total calories. As we wrote earlier about the nutrition label and sugar, if you follow a 2000 calorie diet, you could have about one cup of fruit yogurt and one small dark chocolate bar. That’s because foods with high amounts of added sugar contribute to overweight and obesity, a cause of 10 cancers, including colorectal, postmenopausal breast and kidney.
Unfortunately, the Dietary Guidelines does not reflect the evidence-based recommendation from the independent expert committee to advise Americans to limit red and processed meat. It is disappointing that industry lobbying efforts succeeded in preventing the clear and simple message that these increase risk for colorectal cancer. AICR research has shown that red and processed meats are convincingly linked to colorectal cancer, and the World Health Organization has also recently established that link. Here’s our recommendation:
One of the most common questions we get here at AICR is about sugar. And it can be confusing. The overall body of evidence suggests that sugar’s link to cancer risk is an indirect one: diets high in sugar can lead to obesity, and excess body fat is a cause of ten different cancers.
But now comes a study performed in mice that is getting a lot of media attention. It suggests a more direct link between sugar consumption and breast cancer development. Published in Cancer Research, the study is interesting, says AICR Vice President of Research Susan Higginbotham, PhD, RD, “but it’s important to recognize, that this is a single study and it is testing diets in mice, not in people.”
“Our reports, which have reviewed thousands of studies on diet and cancer, have found no evidence that sugar or added sugar directly causes cancer in humans. “We recommend limiting energy-dense foods and avoiding sugary drinks, but current evidence suggests it is not necessary to avoid sugar altogether.”