The Secret Power of Fiber

by Carole Jackson>, Bottom Line Health

When we think about making sure that we have the healthiest hearts possible, the first thing that comes to mind is what not to eat. Bye-bye, ice cream sundaes, big steaks and fried chicken! But a new study suggests that what we add to our diets — not what we eliminate — may be even more important.

To find out what our hearts (if not our minds) really want us to eat, I spoke to Joseph Carlson, PhD, RD, director of the division of sports and cardiovascular nutrition at Michigan State University’s College of Osteopathic Medicine in East Lansing and the lead author of the study. His research was published in the November 2011 issue of Journal of the American Dietetic Association.

IT WASN’T THE FAT

Dr. Carlson told me that he and his colleagues chose to study teens, in particular, because of the dramatic increase over the past few decades in the number of adolescents with cardiovascular risk factors. And his findings echo what other studies have discovered in terms of adult heart health. They evaluated data from a large federal survey on the health and nutritional status of adults and children. During one part of the survey, 2,100 participants ages 12 to 19 were asked to list everything that they had eaten and drunk in the 24 hours before having a physical exam. Based on their answers, the researchers calculated how many grams of fiber and saturated (“bad”) fat and how many milligrams of cholesterol the youngsters had eaten per 1,000 calories. Then, during the physicals, their cardiac risk factors were assessed.

The results: Compared with those who consumed the most fiber, those who consumed the least fiber were three times more likely to have what’s called metabolic syndrome, which means having at least three of these cardiovascular risk factors — excess abdominal fat… high blood pressure… elevated blood sugar… high amount of triglycerides (blood fats)… and low HDL (“good”) cholesterol. What was even more interesting: Eating less of what we all tend to think of as “bad” foods filled with saturated fat and cholesterol was not associated with a lower risk for metabolic syndrome.

Wait a minute… does that mean that you can throw as much cheese on your omelet as you want — as long as you eat it with whole-grain toast? Unfortunately, no, said Dr. Carlson. Consuming saturated fats and cholesterol can raise your LDL “bad” cholesterol, increase inflammation and hurt your circulation. But these were not components used to evaluate metabolic syndrome in this study. In other words, this research did not show that overdoing saturated fat and cholesterol hurts your cardiovascular health — but we already know that it can. What the study did show, however, is that consuming foods rich in fiber is very powerful for maintaining heart health.

WHY FIBER IS A DIET “MUST”

There are many reasons that adding fiber to your meals may lead to better heart health, Dr. Carlson noted. For one thing, he said, it’s very filling — when you eat more of it, you tend to eat less overall, so you are less likely to be overweight. High-fiber diets, he continued, may also improve glycemic response (the effect of food on blood sugar) and dyslipidemia (an abnormal concentration of cholesterol or triglycerides in the blood). Minerals that may reduce the risk for metabolic syndrome, such as potassium and magnesium, are plentiful in a fiber-rich, plant-based diet, he said. And plant-based foods tend to be high in antioxidants, which may offset oxidative stress and inflammation that are elevated in people with metabolic syndrome.

I know it isn’t news to you that fiber is good for you — but really, before reading this, did you appreciate just how important fiber is? Dr. Carlson told me that Americans’ average fiber intake is less than 15 grams a day, well below the recommendation of 25 grams and 37 grams for females and males, respectively. But this goal can be reached by choosing a variety of fiber-rich foods daily, including fruits, vegetables, whole grains, beans, nuts and seeds. Remember, as a bonus, high-fiber foods fill you up, making you less likely to reach for fatty foods — a win-win for your heart.

Source:
Joseph Carlson, PhD, RD, associate professor and director, division of sports and cardiovascular nutrition, College of Osteopathic Medicine, Michigan State University, East Lansing.