Inflammation is a natural body response. It kicks in when you are trying to recover from a wound or illness, or when you are stressed. But when inflammation becomes chronic, it can lead to diseases like rheumatoid arthritis, heart disease, bowel disorders or cancer.

One good way to reduce inflammation, a new study shows, is by eating nuts — and that's in addition to all the other good things nuts do for you. Nuts contribute to healthy fats, protein, essential vitamins and minerals, fiber and antioxidants to your diet. The result is improved blood pressure, better heart health, a lower risk of diabetes and greater longevity.

People who ate five or more servings of nuts a week had lower levels of inflammation than people who never or rarely ate nuts, even after adjusting for variables such as age, lifestyle and medical history.

Researchers at Brigham and Women's Hospital (BWH) looked at data from 5,000 of the participants in the Nurses’ Health Study and the Health Professionals Follow-up Study. The participants’ dietary questionnaires were compared to their levels of biomarkers of inflammation from blood specimens. Three proteins that act as biomarkers of inflammation were measured: C-reactive protein (CRP), interleukin 6 (IL6) and tumor necrosis factor receptor 2 (TNFR2).

Those people who ate five or more servings of nuts a week had lower levels of CRP and IL6 than people who never or rarely ate nuts, even after adjusting for variables such as age, lifestyle and medical history, the researchers found. And among those who ate nuts in place of meat — whether red or processed — eggs, or refined grains, the levels of these biomarkers of inflammation were significantly lower still.

It's useful to keep in mind that more is not better when it comes to nuts, given the calories they pack, and that peanut butter may not offer the same protective benefits.

“Population studies have consistently supported a protective role of nuts against cardiometabolic disorders such as cardiovascular disease and type 2 diabetes, and we know that inflammation is a key process in the development of these diseases,” said Ying Bao, one of the study authors, in a statement. “Our new work suggests that nuts may exert their beneficial effects in part by reducing systemic inflammation.”

It is not yet known which of the components in nuts are responsible for the positive effect on biomarkers of inflammation. It could be any of the vitamins or minerals they contain, the amino acids, antioxidants, unsaturated fatty acids or any combination of these.

There is also more to learn about the effect of diet on inflammation and the risk of disease in general, according to Dr. Bao, an epidemiologist in BWH's Channing Division of Network Medicine, but this study supports the idea that nuts' ability to reduce inflammation could explain how they work to protect us from cardiovascular disease.

The study is published in the American Journal of Clinical Nutrition.