Fiber — it’s not just good for your digestive tract. For people who have survived a heart attack, eating more fiber could make the difference between dying sooner or living longer.

A new Harvard School of Public Health study found that people who survive a heart attack can reduce their chance of dying over the next nine years by 25 percent simply by eating more fiber, especially cereal fiber.

Even increasing fiber intake by 10 grams per day (the equivalent of eating a cup of whole wheat pasta and a serving of oatmeal) cut the risk of dying by 15 percent over the same time period.

Fiber helps regulate blood sugar levels, and it keeps you feeling full longer after eating which can help with weight control

Researchers analyzed data on nearly 175,000 people from the Nurses’ Health Study and the Health Professional Follow-up Study. Participants complete questionnaires on their health lifestyle habits every other year.

Of the almost 4,000 people who had survived a heart attack, those who ate the most fiber had a 25 percent lower chance of dying from any cause over the next nine years compared with those who ate the least amount of fiber.

Those who ate the most fiber also had a 13 percent lower risk of dying from cardiovascular disease, such as another heart attack, stroke, or coronary heart disease.

Three different types of fiber were compared — fruit, vegetable, and cereal — and only cereal fiber seemed to contribute to longevity after a heart attack, with breakfast cereal being the main source of fiber in the diets of the study participants. Cereal fiber is found in foods like oatmeal, barley, and whole-wheat breads, pasta, and cereals.

While the study points to cereal fibers, all types of fiber play a role in a heart-healthy diet. Fruits, vegetables, legumes, and nuts not only provide fiber, but they are also good sources of key vitamins, minerals, and phytochemicals important to heart health.

Foods rich in fiber help to reduce inflammation in the body, a possible trigger for heart attacks. Fiber also helps keep levels of LDL (the bad cholesterol) down, and this can reduce buildup of plaque in the arteries. And it plays a role in regulating blood sugar levels, keeping you feeling full longer after eating, which impacts weight control and all the diseases and health problems associated with being overweight.

The recommended intake of fiber for women up to age 50 is 25 grams per day, and 21 grams for women over age 50. Men should consume 38 grams per day up to age 50 and 30 grams if they are over 50. Less than five percent of Americans eat the recommended amount. On average, Americans consume only about 15 grams per day.

Lifestyle changes are a cost-effective, low-tech way to increase longevity among heart attack survivors. But their heart benefits have been slow to catch on and most physicians emphasize instead drug therapy, but this study should help change that.

Luckily, people who survive heart attacks are often especially motivated to make lifestyle changes to improve their long-term health, and eating more fiber is an easy change to make.

The study is published online in the British Medical Journal.