Does Eating Plants Help Fight Inflammation?

Rania Dempsey, MD, MS | August 11, 2021

What is inflammation?

When the body suffers an offense (whether from infection, toxin, or injury), it activates the immune system. The immune system sends out inflammatory cells and cytokines (substances that stimulate more inflammatory cells) as first responders to clear infection, neutralize an offending agent, or help heal injured tissue.

Acute inflammation occurs in the short term, when the immune response acts to counteract a sudden insult or injury. When the immune system continues to send out inflammatory cells and cytokines even after the initial offense or injury is addressed, it is chronic inflammation.

Chronic inflammation is involved in the process of many diseases. Previously we thought chronic inflammation contributed only to “inflammatory” conditions such as rheumatoid arthritis and inflammatory bowel disease. But scientists understand now that inflammation plays a role in many chronic diseases such as Type 2 diabetes, heart disease, cancer, obesity, and Alzheimer’s disease.

What causes chronic inflammation?

Chronic inflammation occurs in response to untreated infections (such as bacteria and viruses), toxins, and autoimmune diseases. Lifestyle factors, such as smoking, stress, alcohol, too little or too much exercise, and nutrition also contribute to chronic inflammation.

Does diet affect inflammation?

While current research is inconclusive, studies suggest that blood markers indicating chronic inflammation may be higher in people eating a meat-rich diet compared to those eating lots of fruits and vegetables, and that switching to a whole food plant-based diet may decrease markers of inflammation.

Other studies have found that, in people at high risk for heart disease, a plant-rich Mediterranean diet decreases inflammation compared to controls, and that people with rheumatoid arthritis report a significant reduction in their inflammatory symptoms after 4 weeks on a plant-based diet.

How might eating plants impact inflammation?

There are several potential pathways by which eating plant foods may be linked with reduced inflammation. Whole plant foods are loaded with anti-inflammatory phytonutrients. They also supply the fiber needed to support a healthy gut microbiome, understood to be an important mediator in inflammation. It is also possible that eating lots of plant foods simply means eating less of the pro-inflammatory substances potentially found in meat, including saturated fat, bacteria, and industrial toxins. 

Bottom Line

Whatever the mechanism, eating a variety of whole plant foods including vegetables, fruits, legumes, intact grains, seeds and nuts is a powerful tool for protecting against inflammation-related chronic diseases.