High-fiber Diets and Weight Loss
By Kathleen M. Zelman, MPH, RD, LD
Reviewed By Brunilda Nazario, MD
If you’re overweight and want some help losing weight, start eating foods high in fiber. Dietary fiber is not a magic weight loss weapon, but it has the power to help fill you up without filling you out.
Here’s why: One of the most effective ways to lose those extra pounds is to control hunger, the dieter’s Achilles heel. Hunger is affected by many things, including when you eat, and the composition of your meals – the amount of fats, carbohydrates, protein, fiber, and water content.
Eating healthy high-fiber foods makes you feel full, so you can resist eating more food than you need. Fibrous foods also can take longer to chew, giving your brain time to get the signal that you have had enough to eat.
Read on to learn about losing weight by eating a high-fiber diet.
How Dietary Fiber Helps Weight Loss
Studies show that most people eat about the same weight of food each day, says Barbara Rolls, PhD, author of The Volumetrics Eating Plan. If you choose high-fiber, water-rich foods – such as broth-based vegetable soups, salads, fruits, and vegetables – instead of foods without fiber and water, you can eat the same weight of food but feel full on fewer calories.
A 2009 study in the journal Appetite compared the satiety or fullness factor of apples, applesauce, and apple juice with added fiber before lunch. People who ate an apple before lunch ate 15% fewer calories than those who ate the applesauce or drank apple juice. This suggests that the fiber in the whole apple was more filling even when compared to the juice that had added fiber.
Beyond the fiber content, crunching and chewing a whole piece of fruit stimulates your senses and takes longer to eat. So psychologically, it may also be more satisfying than beverages or soft foods. Chewing also promotes saliva and the
production of stomach juices that help fill the stomach.
Fiber at Breakfast Is a Healthy Weight Loss Habit
In its tracking of the eating habits of successful dieters – those big losers who have kept weight off for years – the National Weight Control Registry has found that most eat breakfast regularly. And cereal is one of their morning rituals.
In general, eating cereal – especially high-fiber cereals – is beneficial for weight loss, says fiber expert Joanne Slavin, PhD, RD, a professor at the University of Minnesota in St. Paul and member of the 2010 Dietary Guidelines Advisory Committee. “Studies that look at what people eat show those who eat more carbs, more fiber, and cereal in general weigh less than those who eat less fiber, carbs, and cereal.”
How Much Dietary Fiber Do You Need?
Most women should get at least 25 grams and most men 38 grams each day to gain all the health benefits of fiber, according to the Institute of Medicine’s Dietary Reference Intake. The problem is that most Americans get only about half that when not on a diet and even less when dieting, especially on low-carb diets.
Tufts University researcher and professor of nutrition Susan Roberts, PhD, has shown that people who eat 35 to 45 grams of fiber a day are less hungry when losing weight and lose more weight than people who eat less fiber. (But beware of consuming fiber as a bulk laxative; it can sap your body of needed nutrients and vitamins.)
“There is no downside to eating a diet rich in fiber,” Slavin says. “And the potential health gains are significant.”
Does Type of Fiber Affect Weight Loss?