Somkiat.cgs/ShutterstockAround 140,000 Americans are diagnosed with colon cancer every year. (Here are the signs of colon cancer you need to be aware of.) Colon and rectal cancers are striking adults at younger and younger ages, and millennials born starting in 1990 and have more than twice the risk of developing colorectal cancer than those born in 1950. “Colorectal cancer is one of the most common cancers,” according to Edward L. Giovanucci, MD, ScD, in a press release by the American Institute for Cancer Research (AICR).
An exciting new report by the AICR and the World Cancer Research Fund (WCRF) yields some good news: “There is a lot people can do to dramatically lower their risk.” The findings are “robust and clear,” Dr. Giovanucci says: “Diet and lifestyle have a major role in colorectal cancer.”
Specifically, the report demonstrates that eating whole grains daily reduces the risk of colorectal cancer by a whopping 17 percent. This adds to previous scientific evidence that foods containing fiber decrease the risk of this particular cancer. The report consisted of a comprehensive analysis of 99 existing scientific studies, including data on 29 million people, of whom over a quarter of a million had been diagnosed with colorectal cancer.
So what exactly qualifies as whole grains?
Our colorectal cancer expert, Darrell Gray, MD, MPH, of The Ohio State University Comprehensive Cancer Center, who was not directly involved in the study but who specializes in gastroenterology and colorectal cancers, explained to Reader’s Digest that whole grains include both the grain’s bran and germ.” The bran is the multi-layered outer skin of the edible kernel. It contains important antioxidants, B vitamins, and fiber. The germ is the part of the grain that has the potential to sprout into a new plant. It contains many B vitamins, some protein, minerals, and healthy fats. “The whole grain is a rich source of phytochemicals and antioxidants that have anticancer properties,” Dr. Gray explains. Further making sense of the connection between eating whole grains and reducing cancer risk, he adds that “whole grains are thought to exert beneficial effects in colorectal cancer prevention by lowering fasting insulin levels.”
How much do we have to eat in order to see these amazing benefits?
According to the study, three servings of whole grains per day (a total of 90 grams) is the magic number associated with the 17 percent decreased cancer risk. The Whole Grains Council, a not-for-profit consumer advocacy group, states that a single serving of whole grain is equal to a 1/2 cup of cooked brown rice, oatmeal, or other whole grain, or a cup of whole grain cereal. Dr. Gray suggests bran-flake cereal, but there are many other options. For foods that contain not only whole grain but also other ingredients (for example, whole grain crackers, granola bars, bread, and muffins), you’ll have to eat a larger amount to get the optimal dose of whole grain.
In addition to eating whole grains daily, the report warns against these habits, which can raise your risk of colorectal cancer:
- Eating lots of red meat such as beef or pork (more than 500 grams, or a little over 1 pound, cooked, per week)
- Eating hot dogs, bacon, and other processed meats on a regular basis (these are the among the foods cancer docs never eat)
- Being overweight or obese
- Consuming two or more daily alcoholic drinks (30 grams of alcohol), such as wine or beer
In addition, the report states that people who are more physically active (at least 30 minutes of physical activity per day) have a lower risk of colon (but not rectal) cancer compared to those who do very little physical activity. It also found limited evidence that eating fish and foods containing vitamin C (such as oranges, strawberries, and spinach) can lower the risk of colorectal cancer, in spite of some claims otherwise.
“All of this points to the power of a plant-based diet,” says Alice Bender, MS, RDN, AICR Director of Nutrition Programs. “Replacing some of your refined grains with whole grains and eating mostly plant foods, such as fruits, vegetables, and beans, will give you a diet packed with cancer-protective compounds and help you manage your weight, which is so important to lowering risk.”
“When it comes to cancer there are no guarantees,” she adds, “but it’s clear now that there are choices you can make and steps you can take to lower your risk of colorectal and other cancers.”
Thinking about changing to a plant-based diet? Plant-based diets have many health perks.