Researchers say the diet of many Americans is increasing their risk for developing a variety of cancers.
Americans still aren’t eating enough of the right foods and are consuming too much of the wrong ones.
And that’s increasing their risk for cancer.
“I would hope that we would be aware that a large amount of new cancer cases is preventable,” said Dr. Fang Fang Zhang, the study’s lead author and an associate professor of epidemiology at Tufts University’s Friedman School of Nutrition Science and Policy in Boston.
Unlike earlier studies that have focused on cancer risks in individuals, this one ascertained the likelihood of the illness showing up in the adult U.S. population as a whole.
It also looked at the incidence of different types of cancer in 2015.
The researchers then came up with estimates of how many of the cancer cases diagnosed each year can be attributed to diets featuring less than ideal amounts of whole grains, dairy products, fruits, vegetables, red and processed meats, and sugary drinks.
What the researchers found is that poor diets accounted for about 80,110 of the cancer diagnoses in 2015.
Most of those cases — 84 percent — were the direct result of patients either not eating enough whole grains, dairy products, and produce or too much meat that’s considered carcinogenic and sugar-sweetened beverages.
Although scientists have long suspected a relationship between diet and cancer, in recent years an explosion of data has shown there’s a direct nexus, says Dr. Anton Bilchik, professor of surgery at the John Wayne Cancer Institute and chief of general surgery at Saint John’s Health Center in Santa Monica, California.
“We now have some real science that we really haven’t had before,” he told Healthline.
He notes that previous studies probing the origins of cancer typically have looked at a combination of risk factors — not just obesity, for example, but behaviors such as smoking and lack of exercise.
Researchers also found disparities among subgroups of the population.
- cancer of the mouth, pharynx, and larynx
- uterine cancer
- breast cancer (postmenopausal)
- kidney cancer
- stomach cancer
- liver cancer
Looking at which diets were most often associated with new cancer cases, scientists determined they were those that skimped on whole grains, such as oatmeal, brown rice, and bread containing whole-wheat flour.
The study’s authors noted that although Americans have been eating more whole-grain foods over the past 14 years, the one daily serving that they were averaging in 2013 to 2014 was still significantly less than the three servings per day the federal dietary guidelines recommend.
Other dietary missteps listed according to the cancer risk they posed from high to low were:
- insufficient intake of dairy products
- eating too much processed meat
- not including enough vegetables and fruits in meals
- overconsumption of red meat
- drinking too many sugar-sweetened beverages
And although the popularity of red meat is waning, this country’s love affair with processed meats has continued unabated for the past 15 years, the study reported.
Americans are eating about 1 ounce per day of this carcinogen on average — more than twice what the American Heart Association advises.
Researchers speculated that the public doesn’t recognize the dangers of processed meats or the health benefits of whole-grain foods.
They’re hoping their findings will turn that around by prompting the government to adopt policies, such as requiring warning labels on foods containing processed meats and restricting the quantities served in school and workplace cafeterias.
Acknowledging that poor diets can start early in life, the study also suggested that policymakers formulate cancer prevention strategies that young people can understand, require schools to limit the availability of sugary drinks, and serve meals that meet higher standards.
“It really is sending a message that you can be physically active (and not) smoke, but if you’re eating poorly, you’re still putting yourself at risk of getting cancer,” he said.
- Grains, especially whole grains (examples are foods containing wheat, corn, rice, or oats): 9 servings
- Dairy products: 2 to 3 servings
- Vegetables: 4 servings
- Fruits: 3 servings
- Low-fat meats, eggs, dry beans, nuts: 2 servings for a total of 6 ounces