A recent study reveals that depression — a mental disorder that affects up to 20% of the population at one time or another — may be caused by inflammation. The study published in the journal Brain, Behavior, and Immunity found striking evidence that people who were depressed had higher markers of inflammation in their blood than the healthy control group.

According to the researchers, these results clearly show that depression is linked to inflammation.

"In the last several decades, we've increasingly understood that chronic inflammation plays a major negative role in our health, contributing to the risk of developing diseases such as diabetes, hypertension, and dementia," Dr. Austin Perlmutter, M.D., co-author with his father, Dr. David Perlmutter, of the blockbuster new book "Brain Wash," tells Newsmax.

"So, we know that inflammation affects our brains and multiple studies have shown that people with depression have significantly elevated levels of inflammation in their blood. More to the point, volunteers injected with chemicals that induce inflammation demonstrated increased symptoms of depressions, indicating that inflammation may actually cause depressive symptoms."

Dr. Gary Small, M.D., author of "The Mind Health Report" and many bestselling books on brain health, tells Newsmax that while anti-inflammatory drugs have been shown to have an antidepressant treatment effect, these medicines are limited because of their potential side effects.

"By contrast, several lifestyle factors have been shown to reduce inflammation and may thus lift mood levels," he says. "People can make sensible choices each day to opt for habits that combat chronic inflammation."

For example, aerobic exercise has a strong anti-inflammatory effect and Small says that some people even notice fewer aches and pains after a brisk cardiovascular workout.

"Maintaining a healthy body weight, getting enough restful sleep, reducing stress, and eating a healthy diet can all help reduce inflammation," says the author of "2 Weeks to a Younger Brain."

"It is also possible to reduce inflammation levels by consuming omega-3 fats from fish or nuts. These healthy fats lower the inflammatory reaction throughout the body and some studies have shown a connection between a diet rich in anti-inflammatory omega-3 fats and better mood."

Perlmutter says that according to research, inflammation also changes the way we think.

"The more inflammation that is present, the more we are more likely to make impulsive, present-focused decisions," he says. "That's why it is more important than ever to take control of sources of chronic inflammation in our lives which includes not only changes in diet and exercise patterns, but also our environmental exposures and stress reduction activities. In 'Brain Wash,' we cover the science linking all of this together, as well as providing an action plan for reducing chronic inflammation and its many consequences."

Dr. David Perlmutter, a board-certified neurologist and author of "Grain Brain," adds: "The leading-edge research linking depression to inflammation totally changes the landscape as it relates to both treating and even preventing this pervasive mental disorder. If indeed inflammation is playing a causal role, it certainly further highlights the potential for lifestyle modification to reduce the risk for a disease for which pharmaceutical intervention has only marginal effectiveness."