Making one change — getting more fiber — can help with weight loss

Nancy Ferrari

Managing Director and Executive Editor, Harvard Health Publishing

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Getting to a healthy weight and staying there is an important way to prevent heart disease, diabetes, some cancers, and other serious conditions. Many of us know firsthand just how hard it can be to reach and maintain that healthy weight. And there’s no shortage of ways to try to get there: You can count calories, carbs, or points. You can cut back on fat or sugar. You can try any number of popular diets that forbid certain foods, or focus on just one (the grapefruit diet, anyone?). Any of these approaches might work for you. Or they might not — in large part because they are complicated.

A study published in today’s Annals of Internal Medicine suggests that something as simple as aiming to eat 30 grams of fiber each day can help you lose weight, lower your blood pressure, and improve your body’s response to insulin just as effectively as a more complicated diet.

Researchers from the University of Massachusetts Medical School compared the effectiveness of two diets with help from 240 volunteers. Half were asked to follow the American Heart Association’s (AHA) diet for preventing heart disease, in which you try to eat more fruits, vegetables, high-fiber foods, fish, and lean protein but also cut back on salt, sugar, fat, and alcohol. The other half were asked to follow a diet in which the only goal was to eat 30 grams or more of fiber each day. Neither group received advice or recommendations for exercise. All of the volunteers had metabolic syndrome — that is, all of them had high blood pressure, high blood sugar, and high cholesterol, and were overweight. This cluster of health issues greatly increases the risk for developing diabetes, heart disease, and stroke.

The participants in each group averaged 19 grams of fiber a day. Both groups lost weight, lowered their blood pressure, and improved their response to insulin. Those following the AHA diet lost a bit more weight (5.9 pounds) than those on the high-fiber diet (4.6 pounds), but both groups were able to maintain their weight loss for 12 months.

The results of the study don’t prove that a high-fiber diet is necessarily as good (or better) for health than the AHA diet or the highly in-vogue Mediterranean diet. What it does tell us is that one simple step can make a difference and that encouraging healthy behaviors may be more effective than discouraging unhealthy ones.

“In addition to weight control, higher fiber diets can also help to prevent type 2 diabetes and cardiovascular disease,” says Dr. Frank Hu, professor of medicine at Harvard Medical School and professor of nutrition and epidemiology at the Harvard School of Public Health. But, he cautioned, it’s best to get fiber from food, not from supplements.

Adding fiber to your diet can be easy and delicious (see “Good sources of fiber,” below). A high-fiber cereal or oatmeal with berries on top is a great way to start the day. For lunch, enjoy a salad sprinkled with chickpeas or kidney beans and some nuts (almonds, peanuts, walnuts, or pecans). Make a stir-fry for dinner using a variety of vegetables, and top with pumpkin or sunflower seeds.

Snacks offer another opportunity to get fiber. Whole fruit, nuts, and seeds, or a berry smoothie with wheat bran or flaxseed are good options, as are dried fruit (prunes, raisins), popcorn, and bean dips paired with veggies or whole-grain crackers.

Good sources of fiber

Food Serving size Fiber (grams)
Fiber One ½ cup 14
All-Bran ½ cup 10
Shredded Wheat 1 cup 6
Oatmeal (cooked) 1 cup 4
Barley (cooked) 1 cup 9
Brown rice (cooked) 1 cup 4
Whole-wheat bread 1 slice 3
Bran muffin 1 2
Spinach 1 cup cooked 4
Broccoli ½ cup 3
Brussels sprouts ½ cup 2
Carrots 1 medium 2
Green beans ½ cup 2
Kidney beans (cooked) ½ cup 6
Lima beans (cooked) ½ cup 6
Baked beans (canned)* ½ cup 5
Pear (with skin) 1 medium 6
Apple (with skin) 1 medium 4
Banana 1 medium 3
Prunes 6 12
Raisins ¼ cup 2
Peanuts* 10 1
Popcorn* 1 cup 1
* Choose no-salt or low-salt versions of these foods.



  1. Lisa Ryan

    Taking pills for losing weight is not good I think. But, good foods and healthy diet can help us to loss extra fat naturally. Anyway, thanks for this awesome article!

  2. Luis

    Read the fine print. When you are grocery shopping, don’t be fooled by packaging that gives the impression of containing healthy food. Don’t assume that because it is “low-fat” or “organic”, that it is healthy. Take a second to flip the box over and read the nutrition information panel and ingredient list to determine its nutritional content for yourself.

  3. Angelmeds

    Thanks for this nice blog post.

  4. Joao

    Interesting stuff here…thank you very much!
    Of course with nice food and praticing exercises, we can lose weight healthy, without using remedy…

  5. The HCG Institute

    Wow! Nice suggestions, I believe that natural fiber is one of the best things to have. I would like to add something about water. A daily intake of 7 to 8 glasses can do wonders for your health especially with the weight loss. Keep posting such nice suggestions. Thanks!!!!

  6. jivko

    Of course with good food, we can lose our weight healthy without pills and something like that.
    With good food and with more practise we can be in a good shape.

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