Everything You Think You Know About Carbs Is Wrong

For starters, eating carbs won't make you gain weight.

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It's easy to write off carbohydrates as the enemy. After all, many of us grew up hearing the praises of Atkins, and you probably know at least one person who won't shut up about how going keto gave them the body of their dreams. What do both diets have in common? Cutting carbs.

But don't fall for it — forgoing carbs is not the golden path to weight loss, and certainly not the answer to feeling less bleh after indulging in some of your favorite foods. In fact, you're less likely to gain weight — and even develop some serious diseases — if you eat more carbs, says nutritionist Lisa Young, Ph.D., R.D.N., adjunct professor of nutrition at New York University and author of Finally Full, Finally Slim. Here, experts explain what you really need to know about incorporating carbs into a healthy diet.

Not All Carbs Are Created Equal

First thing's first: Even though most of us automatically associate carbs with grains, they are just one type of carbohydrate — as are fruits, vegetables, sugars, alcohol, and even some dairy. (A carbohydrate actually just refers to a type of organic compound found in foods that contains two parts hydrogen to one part oxygen.)

You can divide carbs up a few ways, such as sugars, fiber, and starch; but in terms of healthy and unhealthy, there are two categories: whole and refined.

"Whole" refers to anything that still has its original chemical composition. With, say, a kernel of wheat, it has an endosperm, bran, and germ, the latter two being where all the fiber, vitamins, and minerals are stored. For refined carbs, though, manufacturers strip out the healthy germ and bran and just leave the endosperm center.

Science lesson aside, this distinction is crucial. "Processed carbs are rightly vilified. They're missing the fiber, which helps you feel full, along with the micronutrients and antioxidants that help protect against diseases," Young explains. They're also crucially helpful for digestion.

Eating Carbs Is Way Better Than Cutting Them

A study in The Lancet found that over the course of 25 years, people who scored 50 to 55% of their diet from carbs were the least likely to die. (For perspective, a low-carb diet caps that intake at roughly 30% and keto somewhere between 5 and 10%.)

Now, there is a limit — people who ate either low-carb or high-carb in The Lancet study had a higher mortality risk, so too much is just as bad as too little.

But there's something to be said of the risk of too little, like what chronic Keto-ers consume: A study in the European Heart Journal involving some 25,000 people found folks with the lowest carb intake actually had the highest risk of cardiovascular disease, stroke, cancer, and overall mortality. What's more, despite these diseases often being tied to those who are heavyweight, non-obese people were actually the most at risk for overall mortality.

Why? Because low-carb dieters are cutting carbohydrates and upping their fat and protein, they often eat more animal products and fewer vegetables and fruit, Young says. That means an increase in saturated fat which is tied to heart disease and a decrease in antioxidants that help fight disease-causing free radicals.

FWIW, The Lancet study does distinguish that low-carbers who swapped in plant proteins and fats had a lower risk of disease than their counterparts who loaded up on animal products. But moderate carb intake was still tied to the lowest disease risk, and other studies have reported that people on a low-carb diet are more likely to be deficient in certain nutrients like thiamin, folate, vitamin C, calcium, magnesium, and iron.

Healthy Carbs Will Help You Lose Weight

Avoiding serious illness and even premature death feels like reason enough to include carbohydrates in your diet, but let's address the elephant in the room, which is that most people who cut carbs in the first place are doing so in an effort to lose weight. Pretty much anyone who tries the keto diet raves about how easy it is to drop pounds. And it's true that cutting carbs reduces water weight, says Maggie Moon, MS, RD, Los Angeles-based registered dietitian and author of The MIND Diet. But carbohydrates don't make you retain fat.

"Keto-style diets may seem effective at reducing body fat for a variety of reasons," she says. "But long-term studies don't show keto holds any magical benefits over low-fat diets for maintaining weight loss."

In fact, a Stanford study of more than 600 adults found people who followed a healthy, low-fat diet — eating about 50% carbs, 30% fat, and 20% protein — lost the same amount of weight in three months as folks who ate a healthy, low-carb diet (30% carbs, 45% fat, and 25% protein). That's probably because they ended up eating about the same number of calories naturally.

The consequences of unhealthy carbs are what give us this false association: A small study in American Journal of Clinical Nutrition had 12 people eat the same number of calories, but from foods that vary on the glycemic index (a measure of how quickly your blood sugar shoots up).

Researchers found that after people ate foods high on the glycemic index (i.e., white bread, white pasta, and processed carbs), they were hungrier and had more activity in the parts of their brain associated with reward and cravings in the hours after eating, which directly influences what you'll eat at your next meal. When they ate non-processed foods low on the glycemic index, this wasn't a problem.

At the end of the day, gaining weight is still about excess calories in, Young says. And healthy carbs are loaded with fiber, which aids in satiety, helping you feel full and signaling to you when to stop eating so you don't overeat, she explains.

Carbs Help You Work Out Harder

Of course, if weight loss (or weight maintenance) is your goal, exercise is the other part of the equation. But daily exercise is also directly tied to heart health and lower disease risk — and carbohydrates are the body's preferred source of fuel for said exercise.

Yes, your body can learn how to become fat-adapted and convert fat to fuel as every low-carber argues — but it's way harder. Even if you become fat-adapted, you can't convert fat to fuel at the same rate you can carbs to fuel, Young explains. For example, athletes who followed a super low-carb, ketogenic diet had less power output during short, high-intensity bursts of exercise, says a study in the Journal of Sports Medicine and Physical Fitness.

That efficient conversion makes carbs just as important for endurance exercise, Moon adds. An hour into your run or bike when your carb/glycogen stores have been completely depleted, replenishing them can give you more energy to stick with the cardio for longer, far better than the slow-burning fat. And reloading depleted glycogen stores ASAP post-workout will help you recover and perform better for the next workout, she adds.

How to Overcome Carb-Phobia

So, some carbs are better than none — but how do you tell which are healthy and which are a sugar trap? If you're worried about navigating this carb-heavy time of year or thinking about reevaluating your diet in the new year, these six guidelines can help keep you on the right track:

1. Don't Assign Emotional Baggage to Food

"Foods, including carbs, aren't morally good or evil — they're just food," Moon says. Take away the emotional load and you're left with science: What will and won't make my body feel good.

2. Steer Clear of Anything White, Unless It's a Whole Vegetable

"For the most part, white means refined," Young says. The next step is to read the ingredients, but generally, the only good food that's white comes from potatoes, turnips, cauliflower, or tofu — and it's usually pretty easy to tell if what you're holding is the blank color because of that or because it's been uber-processed.

3. Eat Closer to Nature

You've heard this before, but it's honestly the best rule in differentiating healthy carbs from unhealthy ones, Moon says. Opting for a baked sweet potato instead of sweet potato chips or an apple over apple juice not only guarantees you're choosing healthy carbohydrates instead of the refined version, but feeling energized and fueled with the cleaner variety can help rewrite your associations that carbs are bad.

4. Only Eat Grains That Say "Whole"

Packaging that says "multi-grain" or just "wheat" are taking you for a sucker. "If it doesn't say 'whole' before a grain on the nutrition label, it's been processed and is missing that optimal nutrients and fiber," Young says.

5. Fill One-Quarter of Your Plate With Whole Grains or Starchy Vegetables

Remember, eating too many carbs regularly ups your risk of major diseases just as much as too few carbs. Don't miss out on the good, but try not to have too much of a good thing, either.

6. Eat as Many Vegetables and Fruit as You Want

Produce is super low in calories and incredibly high in fiber to help you avoid overeating, making it a great addition to any meal. Unless you're following a specific macro plan, the carbs in fruits and vegetables won't topple your plate portions — and should actually comprise half of every meal, Young says. (That last quarter should be protein.)

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