Fiber’s Dubious Benefits

Wrote this in response to someone attempting to paint low-carb as nutritionally deficient yet again. In the tradition of “low-carb makes Matt all ranty”, I’ll toss it over the wall yet again.

Because [low-carb] avoids Grains,Fruits and Vegetables, so you don’t take sufficient micronutritients.

That question is based on an incorrect assumption. If you aren’t eating huge amounts of green leafy veggies — among other vegetables — you aren’t low-carbing right. According to my Fitday profile, the only deficiency I have regularly just from dietary sources is Potassium. This is common among Americans, and most of the very potassium-rich foods are also carbohydrate-rich. I work around this through supplementation, and comparing my pre-TSPA diet to my post-TSPA diet, I’m way way way way more covered on all the nutritional bases.

It’s a common fallacy that low-carbing is nutritionally incomplete.

There is one other dietary fallacy that I want to address: fiber. The only benefit of fiber for a low-carber* is the slowdown of the absorption of carbohydrates in the bowel and relief from constipation. There’s no benefit to colon cancer or overall health other than steadying blood insulin… which low-carb does better. Here are the so-called benefits of a high-fiber diet: * Reduction of heart disease. Fiber slows the absorption of carbohydrates, which steadies blood sugar. Low-carb reduces carbohydrate entirely, which also steadies blood sugar. * Reduction of cancer rates. Shown false this year in a Harvard study once you eliminate the variable of obese people. Obesity increases cancer risk, and obese people tend to eat less fiber. Low-carbing reduces obesity in far superior numbers to eating more fiber (viz: “Good Calories, Bad Calories” by Gary Taubes stresses this topic). * Reduction of diabetes. Once again, this is because fiber slows down sugar absorption rates… a redundant function for a low-carber! * Reduction of diverticulitis. A high-fat, low-fiber diet is among the healthiest treatments for diverticulitis or Crohn’s disease (see: Lutz, “Life Without Bread”). * Reduction of gallstones & kidney stones. These are both responses to the release of large amounts of glucose into the bloodstream, which low-carb controls. Consumption of large quantities of water — also advocated by virtually all low-carb eating plans — dramatically reduces both types of stones.

So for the low-carber, fiber is redundant and unnecessary unless you get stopped up. Period. Every benefit of fiber is reproduced by a low-carb, high-fat diet, and there is no further health benefit for a low-carber other than fixing irregularity. For many of us — self included — eating low-carb stabilizes stools with or without meeting the US RDA for fiber.

Regards, Matt B.

* Note: Thank you, Marochka Raduga, for pointing out that fiber also increases satiety with meals, and for those who have trouble maintaining satiety on low-carb fiber may help them feel fuller longer.