Hamburgers, fries, sugary sodas, and other less healthy foods may cause inflammation, a key player in the formation of artery-clogging plaque.
Eating foods such as red meat and sugary treats may trigger inflammation, raising your risk of cardiovascular disease. But a diet rich in fruits, vegetables, and other anti-inflammatory foods reduces the risk, according to a large Harvard study.
“These new findings help explain why certain foods we consider unhealthy may be contributing to plaque buildup inside arteries,” says Dr. Kathryn Rexrode, associate professor of medicine at Harvard Medical School and a co-author of the study, published last year in the Journal of the American College of Cardiology. Inflammation is marked by the release of molecules called cytokines into the bloodstream. These attract immune cells to artery walls, contributing to the development of plaque, she explains.
Markers of inflammation
The study included more than 210,000 women and men who filled out dietary questionnaires every four years. After a follow-up that lasted up to 32 years, people with the most pro-inflammatory diets had a 46% increased risk of heart disease and a 28% increased risk of stroke compared with those who had the most anti-inflammatory diets (see “Food and drinks that cause or prevent inflammation”). In a subset of just over 33,700 of the participants, pro-inflammatory diets were linked to higher blood levels of three inflammatory markers.
Exactly why some foods cause an inflammatory response in the body isn’t fully understood. But there’s been increasing interest in how foods affect the gut microbiome, says Dr. Rexrode. The food we eat influences the types of bacteria that populate our gut and the resulting chemical byproducts. While certain foods encourage the growth of populations of bacteria that promote inflammation, others foster the growth of bacteria that suppress it.
Another problem may be that filling up on fatty, sugary foods reduces intake of healthful foods with anti-inflammatory properties. Most fruits and vegetables are rich in compounds known as antioxidants and polyphenols that may dampen inflammation. Coffee and tea (especially green tea) are also brimming with these potentially protective substances. And studies show that swapping whole grains for refined grains lowers levels of inflammatory markers in the blood.
Foods and drinks that cause or prevent inflammation
A long-running dietary study documented that people whose diets included more pro-inflammatory foods had a 38% higher risk of cardiovascular disease compared with people who had the most anti-inflammatory diets.
Making the switch
It’s not always easy to transition from a pro-inflammatory to an anti-inflammatory diet. “Many processed foods, especially salty, fatty, or sweet snacks, are designed to make you want to eat more of them,” says Dr. Rexrode. Food manufacturers do that on purpose because they want you to buy more of their products.
People who don’t like to cook and rely on takeout food for the bulk of their meals tend to have the hardest time changing their diets, Dr. Rexrode says. Changing your shopping habits is the first step. She also advises her patients to start with a few small changes and build gradually from there. Here are some suggested swaps:
- Breakfast: Instead of a bagel, try oatmeal. To save time, make a big batch and divide it into containers that you can pop in the microwave each morning. Add cinnamon, berries, and chopped nuts for extra flavor and anti-inflammatory nutrients.
- Lunch: Switch the deli meat on your sandwich with sliced chicken breast you roast yourself. Better yet, try a bean-based spread such as hummus, plus avocado and other sliced vegetables. Use whole-grain bread.
- Dinner: Choose brown rice, quinoa, or farro instead of white rice. Have sweet potatoes instead of white potatoes.
- Dessert: Reserve cake, pie, ice cream, and similar treats for special occasions instead of indulging every night. Have fruit for dessert, but try something more exotic than you normally get, such as a peach, pineapple, or mango.
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