FiberOne of the most tragic casualties of a strictly low-carb, low-fat diet is the dismal disappearance of the dieter’s fiber intake. So what’s a dieter to do? Sacrifice their carb count for a fiber count? What is fiber, anyway? How important is it to nutrition and weight loss? Or, put simply: if I’m trying to lose weight, should I avoid or aim for fiber?

What is Fiber?

Fiber is the undigested plant material that, while found in a beautifully broad range of foods—from beans and nuts to oats and broccoli—is, ironically, consistently underrepresented in the typical American’s diet.

The average American adult consumes about half of the USDA’s daily recommendation of roughly 25 grams of fiber; for men under 50, the USDA recommends 30-38 grams, to reflect guys’ higher daily calorie intake. (Check out Table 1, below).

There are two kinds of fiber: soluble and insoluble. Soluble fiber—found in foods like oatmeal, lentils, apples, strawberries, flax, and beans—attracts water and forms a gel, which slows down digestion and keeps you feeling fuller, longer. Insoluble fiber—found in whole grains, broccoli, nuts, and dark leafy veggies—act as a natural “broom” for your digestive track, speeding up the passage of food and waste in a timely and—shall we say—regular manner.

Both types of fiber are therefore a key nutrient in a smart, healthful weight loss program.

Beyond Better Bowels

More than helping to keep your bowel movements healthy and regular, some fibers have been shown to possess important anticancer, antibacterial, and antiviral properties. These soluble fibers, called lignans, also demonstrably combat type 2 diabetes by slowing down the absorption of glucose, increasing the sensitivity to insulin, and thereby improving glucose metabolism overall.

With increasing attention paid these days to “gut health”—measured by the robustness and diversity of beneficial bacteria in our digestive tracks—and the role that this community of microbes plays in our overall health (including our individual propensity toward weight gain and retention), fiber fans are vindicated again. In your gut, bacteria ferment a type of soluble fiber called inulin, and uses it to fight pathogens, which is why inulin is referred to as a “prebiotic.” Artichokes, leeks, garlic, onions, and tofu are all sources with high levels of inulin (see Table 2, below), but be careful how you cook them: overcooking these foods can drastically undercut the presence of fiber.

Fiber Fill-Up

Even though at first it may seem daunting to aim to double your usual fiber intake, your emphasis should be on diversity of foods, not fiber counting per se. By incorporating a broad range of fiber-rich foods (again, Table 2 is your guide), you will not only likely hit your fiber intake goal, but you will also improve the diversity and health of your gut, as well as reaching a variety of other daily nutritional goals. Plus, the added benefit that fiber leaves you feeling fuller, longer, will leave you less likely to reach for that mid-afternoon bag of chips or snack bar.

Here are some tips on how to work more fiber, effortlessly, into your day:

•      Start the day with a good dose of fiber. Choose a cereal with “whole grains” as the first listed ingredient, with at least 5 grams of fiber        listed on the label. Bran, flax, and oats are usually good signifiers.

•     Ditch the juice and eat a piece of whole fruit—skin included—instead.

•     Add a tablespoon of ground flaxseed to soups, salads, stews, and smoothies.


Table 1. USDA Fiber Recommendations*

Men, below 50 years old

38 grams

Men, above 50 years old

30 grams

Women, below 50 years old

25 grams

Women, above 50 years old

21 grams

*based on the average healthy adult. Always check with your medical provider or nutrition adviser if in doubt.


Table 2. Fiber-rich foods


Total Fiber (in grams)

Bran cereal

1/3 cup


Split peas, cookd

1/2 cup


Kidney beans, cooked

1/2 cup


Lentils, cooked

1/2 cup


Black beans, cooked

1/2 cup


Chickpeas, canned

1/2 cup






1/2 cup



1/2 cup


Sweet potato, baked, with skin

1 medium


Potato, baked, with skin

1 medium



1/4 cup



1/2 cup



1/2 cup



1 ounce


Cooked spinach

1/2 cup



1 medium