What you eat — or don’t eat— could affect your risk of developing cancer more than you might think. When nutritional researchers looked at the modifiable risk factors associated with cancer and compared them to the typical American diet, they found that the impact of diet on cancer risk was the same as that of alcohol.

Cancer is the second leading cause of death in the U.S. Last year, approximately 1.7 million people were diagnosed with cancer, and over half a million will die from it. A poor diet, one with too little fiber and too few fruits and vegetables, raises the risk of developing cancer, so narrowing down the dietary factors that increase the risk is important; especially in light of the fact that obesity is an important risk factor for 13 types of cancer, and the obesity crisis continues to escalate.

Of all the diet-related cancers, about 16 percent were related to obesity.

Tufts University researchers studied the connection between a person's intake of seven dietary factors — eating too few fruits, vegetables, dairy products and whole grains, while eating too much red meat, processed meat and sugar-sweetened beverages — and the recorded cases of cancer in 2015. They used diet information from two cycles of the National Health and Nutrition Examination Survey (2013-14 and 2015-16) and compared that information to cancer cases diagnosed and recorded by the Centers for Disease Control and Prevention and the National Cancer Institute.

Over 80,000 new cases of invasive cancer reported in 2015, or a little over five percent of the year’s total among U.S. adults, were related to dietary factors. For comparison’s sake, alcohol is associated with four to six percent of cancer cases.

Not eating enough whole grains was associated with the greatest number of new cases of cancer, followed by not eating enough dairy foods, eating excessive amounts of processed meats, a low intake of fruits and vegetables, eating too much red meat and drinking too many sugary beverages.

How to Tweak Your Diet

Eating too few whole grains and dairy foods and too much processed and red meats were associated with having an increased risk of colorectal cancer. Diets low in fruits and vegetables increased the risk of cancer of the mouth, pharynx and larynx. A diet high in processed meats, like bacon and hot dogs, increased the risk of stomach cancer.

The greatest number of diet-related cancers were those of the colon and rectum at 38 percent of all cancers diagnosed. Cancers of the mouth, pharynx and larynx were next, at nearly 26 percent of cases. Of all the diet-related cancers, about 16 percent were related to obesity.

Looking at actual numbers, dietary factors were related to over 52,200 cases of colorectal cancer, over 14,400 cancers of the mouth, pharynx and larynx, more than 3,100 cases of uterine cancer, and over 3,000 cases of breast cancer in postmenopausal women, 2,000 kidney cancers, 1,500 stomach cancers and 1,000 liver cancers. Men, middle-aged Americans (ages 45-64), and some ethnic groups, including African Americans and Hispanics, were more often diagnosed with cancer than other groups.

Diet may be only one of several factors that affect your risk of developing cancer, but it is one that you can control.

The study underscores the importance of a healthy diet in reducing the risk of cancer. Diet may be only one of several factors that affect your risk of developing cancer, but it is one that you can control. It is a modifiable risk factor.

Yes, it is true that anyone can get cancer no matter how well they eat or how much they exercise or avoid alcohol and tobacco, but since dietary guidelines pretty much mirror the recommendations for preventing other diseases, healthy eating is a win-win.

The science is pretty clear. To reduce your risk of developing cancer eat less red meat, processed meat and sugar (including sodas); enjoy some low-fat dairy foods; and, as always, eat more fruits, vegetables and whole grains.

The study is published in JNCI Cancer Spectrum.