#170 Should I Avoid Carbs?

Should I Avoid Carbs?

Should I avoid carbs is something I am asked all the time.  Indeed, the low-carb craze today differs little from the fat-free craze a generation ago and, for that matter, the low-protein craze a hundred years ago.

Diets are like fads, they go in and out of style because they aren’t based on science. That’s why I hate the word “diet.” It turns something that couldn’t be more natural, food, into something harsh and rigid.

Not All Carbs Are Created Equal

Here’s the thing: Not all carbs are created equal. While it is true that carbs from sugar and processed foods cause weight gain — and lots of it — carbs from vegetables, legumes and fruit have the exact opposite effect.

In general, what determines whether a carb causes weight gain or weight loss is determined by how fast it is converted to sugar in our bodies. The flour in even a slice of whole wheat bread, for example, is converted to sugar faster than a Snickers bar. In contrast, broccoli carbs — yes, there are carbs in broccoli — take hours to digest. Those are good carbs.

The Science on Weight Gain and Carbs

In a study that looked at more than 130,000 people over nearly a quarter century of food consumption, researchers from Harvard and Tufts University found that the more carbs you get from vegetables, fruits and legumes the less you will weigh. Meanwhile, another Harvard study — this one including 120,000 people — showed that the more carbs you get from sugars, sweets and processed foods the more you will pack on the pounds.

Want more proof?  The longest lived people in the world, the people of Okinawa, Japan, who also happen to probably be the healthiest and leanest people as well, eat mostly carbs – the good ones.

Avoiding all carbohydrates because things like processed bread can contribute to weight gain is like avoiding all liquids because soda pop is a scourge to public health. In my experience, the number one factor of weight gain or weight loss is the type of carb you pick.

Tip: Get to know your carbs.

There’s a tremendous difference between filling carbs and hunger carbs. And once you understand the difference, it makes it a lot easier to decide which is which.

The Filling Carbs

Filling carbohydrates are a part of “real food,” which is how I think about food that isn’t highly processed (or processed at all, for that matter.) Sweet potatoes have good carbs. So do vegetables, fruits, beans, lentils, and unprocessed grains. These carbs fill you up and keep you satiated for a long time.

The Hunger Carbs

Hunger carbohydrates are a very big part of “fake food,” which includes just about anything that doesn’t look like the ingredients from which it is made. This includes processed breakfast cereals, potato chips and most breads — especially those that are made from pulverized, very fine flour.

Take Home Message on Carbs

The best way to get to know your carbs is to memorize a very simple mantra from food guru Michael Pollan: “If it came from a plant, eat it. If it was made in a plant, don’t.”

Do you limit carbs?  If so, which carbs?

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  1. Hi Dr Day,
    I have had the type eating plan you recommend for about 10 years. I figured it out myself when I became diabetic. I tested every food on my blood to see it’s effect. I do not eat my own whole grain bread as it raises my blood sugar too much. (I have a small bakery and make lower carb high fiber bread.) After 25 years of type two diabetes, I have no heart disease, nerve damage and am in very good health and have been normal weight for many years. When diagnosed I was 55 lbs over weight. In addition to the type carb diet you recommend, I would add fiber especially soluble fiber. I use High maize 260
    resistant starch fiber because I can add it to other foods. The added fiber keeps my blood sugar steady, lowers cholesterol and feeds my gut bacteria. I also increased the fat content of my diet. I have no trouble keeping my weight down as I am never hungry. I swim laps 3 days of week do weight machines 3 days a week along with aerobic exercise. I take 16 units of Lantus as I don’t make enough insulin. I am 78 years old and have lots of energy.

    • Hi Rosalie,

      Thanks for sharing! I agree, eating high fiber and low glycemic foods can be very helpful for diabetes, weight loss, etc.



  2. I find the glycemic index/glycemic load concept to be particularly helpful in managing carbs. 14 years ago I was diagnosed as a type 2 diabetic. At the time my A1c was 6.2. After controlling carbs via the glycemic index (and losing weight) I managed to keep my A1c below 6 for 13 years. (It has finally gone up slightly above, but I’m fighting it hard.) The link below provides a good overview. (Note how outrageous baked potatoes are…and how powerful peanuts are in reducing the glycemic load. I always add peanuts to yogurt, ice cream or rice…all of which I generally avoid, however 😉


    • Hi John,

      I agree, keeping the glycemic index/load as low as possible is a healthy way to eat not just for diabetics but for everyone else as well.

      Thanks for sharing!