The Truth About Carbs And Calories Carbs get a bad rap. Here's the science behind why eating too much starch isn't good for you — and smart tips to integrate more slow carbs into your diet.
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The Truth About Carbs And Calories

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The Truth About Carbs And Calories

The Truth About Carbs And Calories

The Truth About Carbs And Calories

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C.J. Burton/Corbis/Getty Images
A loaf of bread made out of sugar cubes.
C.J. Burton/Corbis/Getty Images

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We are not here to vilify carbs — they're fuel for our bodies — but not all carbs are created equal. We look at the science behind why eating too much starch isn't good for you and share four tips to help you integrate grains into your diet.

1. Not all calories act the same in the body.

Just because two foods have the same number of calories doesn't mean they're equal health-wise. "We've known for decades, if not a century, that different foods affect the body differently, apart from their calorie content," says David Ludwig, a professor of nutrition at the Harvard T.H. Chan School of Public Health and the founder of a weight loss center at Boston Children's Hospital.

If you take white bread and whole-grain wheat kernels that have about the same number of calories, the whole grain has so much more going for it. Eating minimally processed grain like wheat berries, whole oats, barley and rye is better for you than superprocessed white bread. Ludwig says that's because they take longer to digest. "Blood sugar rises relatively more gently. You produce less insulin, calorie for calorie."

When you eat white bread, on the other hand, all the good-for-you stuff is processed out of the bread, leaving a bunch of starch, which can raise blood sugar and insulin, potentially stimulating hunger and maybe even slowing down your metabolism.

2. Refined carbs quickly turn to sugar in your body.

You've heard to cut back on sugar. But consider this: Ultra-refined grains (whether it's crackers, baguettes or white bread) are just one step away from turning into sugar in our bodies. And as we just outlined, ultra-processed, starchy foods can raise blood sugar and insulin. Ludwig says this can direct calories more into storage and fat cells, meaning "there are fewer calories available for the rest of the body, for the organs, the muscles and the brain," he says. "That's why we get hungry."

Don't worry — you can still eat bread. There are just much better options than white bread. For example, traditional pumpernickel, sourdough or other whole grains.

What does the phrase "whole grains" really mean? Whole grains have three parts. In the center, there is a germ. Think of it as a tiny packet of nutrients — it has protein and a few essential fatty acids. Then there is the bran, which is fiber — that's good for digestive health. The third part of the grain is called endosperm, which is usually what's left in processed carbs. It's really just starch. However, when you eat whole grains, you get all three parts.

3. Treat bread like dessert. (Eat it last.)

A study a few years back gave people bread rolls at the end of a meal versus the beginning of a meal. The researchers found, on average, that the people who ate those rolls at the end had about a 30% lower peak in their blood sugar. If you love breads and muffins, save them for the end of your meal.

"There's that expression, 'Life is short — eat dessert first.' Not in this case," says Ludwig. "Dessert is designed to come after the meal, when your stomach has already got protein, healthy fats and fiber slowing down digestion."

4. Eat whole foods, healthy fats and protein.

Focus on reducing highly processed carbohydrates and replacing them with whole fruits, beans, nuts and a variety of healthy fats, making sure to get enough protein. And remember not to be afraid of minimally processed "slow" carbs.

So how do we put this into practice in the kitchen? Dawn Ludwig, a professional chef, takes David Ludwig's science and translates it into practical meal tips. (They also happen to be married.) She shared some sauce recipes with us that she uses to dress up veggies, protein or whole grains — her secret sauces, if you will.


Recipes: Dawn Ludwig's 5-Minute Sauces

From Always Delicious, by David and Dawn Ludwig, and Always Hungry?, by David Ludwig. Used with permission.

Cashew Balsamic Dressing

Prep time: 5 minutes. Makes about 1 cup.

2 1/2 tablespoons soy sauce
1 1/2 tablespoons balsamic vinegar
2 tablespoons water
1/2 cup neutral-tasting oil, such as high-oleic safflower or avocado oil
1/4 cup cashews

Place all the ingredients in a wide-mouthed Mason jar or cup that will fit an immersion blender without splashing. Pulse a few times to blend until the cashews are in small pieces but still chunky.

Place a lid on the jar. For best results, set aside for at least one hour to allow the flavors to develop. The dressing will keep in the refrigerator for one to two weeks.

Ginger Tahini Dressing

Prep time: 5 minutes. Makes about 1 cup.

1/4 cup tahini
2 tablespoons white miso paste
1 2-inch piece ginger, peeled and thinly sliced
2 teaspoons rice vinegar
1 teaspoon soy sauce
1/2 cup warm water

Place all the ingredients in a wide-mouth Mason jar or cup that will fit an immersion blender without splashing. Blend, working the blender into the pieces of ginger until smooth. Add additional water as needed to reach the desired consistency.

Place a lid on the jar. For best results, set aside for at least one hour to allow the flavors to develop. The dressing will keep in the refrigerator for one to two weeks.

Moroccan Sauce

Prep time: 7 minutes. Makes 2/3 to 3/4 cup.

1 2-inch piece fresh ginger, peeled and sliced into thin rounds
3 medium cloves garlic
1 3- to 4-inch piece fresh turmeric, peeled, or 1 teaspoon ground turmeric (optional)
2 teaspoons paprika
1 teaspoon ground cumin
1 teaspoon ground coriander
1/2 teaspoon ground cinnamon
1/4 teaspoon ground cloves
Dash of freshly grated nutmeg
1/4 teaspoon ground white or black pepper
9 or 10 sprigs cilantro, stems and leaves coarsely chopped
1/4 cup extra-virgin olive oil
1/4 cup water
1/2 teaspoon salt
Dash of cayenne pepper, or to taste (optional)

Place all the ingredients in a wide-mouth Mason jar or cup that will fit an immersion blender without splashing. Blend, working the blender in the jar until the garlic, ginger and turmeric are smooth.

Place a lid on the jar. For best results, set aside for at least one hour to allow the flavors to develop. The dressing will keep in the refrigerator for up to two weeks.

Thai Peanut Sauce

Prep time: 5 minutes. Makes about 1 3/4 cups.

1 large orange, 4 small clementines or 2 large tangerines, peeled, seeded and cut into 1-inch pieces
1 1/2-inch piece fresh ginger, peeled
1 teaspoon fresh lime juice
1/2 cup peanut butter (no sugar added)
1 teaspoon unseasoned rice vinegar
2 tablespoons water
1 tablespoon soy sauce
1/4 teaspoon salt
1/4 to 1/2 teaspoon cayenne pepper, or to taste

Place all the ingredients in a wide-mouth Mason jar or cup that will fit an immersion blender without splashing. Blend until the orange is fully blended and the sauce is thick and creamy. Adjust seasoning to taste.

Place a lid on the jar. Allow the flavors to develop for one hour or more in the refrigerator. The dressing will keep for about a week.


Here's what to remember:

  1. Not all calories act the same in the body.
  2. Refined carbs quickly turn to sugar in your body.
  3. If you love breads and muffins, save them for the end of your meal. Treat bread like dessert.
  4. Focus on slow carbs that take longer to digest. Think whole fruits, beans and whole grains.

Chloee Weiner produced the audio portion of this story, which was originally published on Jan. 21, 2019.