In recent years, keto and other low-carb diets have become popular among many people trying to drop unwanted pounds. The eating regimen has been touted by some celebrities, including Kourtney Kardashian, Halle Berry and Vanessa Hudgens. In 2014, basketball superstar LeBron James revealed that a low-carb eating regimen had helped him drop weight and posted photos on social media showing his leaner frame.
Whether you’re a celebrity or not, if you’re adhering to the keto diet or another low-carbohydrate eating regimen, the only carbs that matter are net carbs, says Colette Heimowitz, vice president of nutrition communication and education for Simply Good Foods Company. The company is the parent company for Quest Nutrition and Atkins. She’s also the author of “The Atkins 100 Eating Solution: Easy, Low-Carb Living for Everyday Wellness.”
[See: Favorite Keto Recipes From America’s Test Kitchen.]
What Are Net Carbs and Why Do They Matter?
Net carbs refers to the total number of carbs in food, minus carbs that your body won’t absorb, says Natalia Groat, a registered dietitian with UW Medicine at Harborview Medical Center in Seattle. The center is managed by UW Medicine, the formal brand name of the University of Washington’s health care system. The categories that you’d subtract because your body won’t absorb much of fiber and sugar alcohols (though some are partially absorbed by the body), Groat says.
Adherence to the keto diet or another low-carb eating regimen calls for strictly limiting your intake of net carbs, to about 20 net carbs a day or less, depending on the diet.
In addition to keto, other well-known low-carb eating regimens include:
— Atkins diet.
— Paleo diet.
If you’re a newcomer to the keto diet or another low-carb regimen, a quick summary of why proponents say these diets are good for weight loss may be helpful.
Keto diet advocates say that by slashing your intake of carbs and consuming more fats, your body can safely enter a state of nutritional ketosis. That’s when the body breaks down dietary and stored body fat into substances known as ketones. At that point, your body’s fat burning system primarily uses fat — rather than sugar — for energy.
It’s good to keep in mind that a low-carb/keto eating regimen is inconsistent with federal eating guidelines. The 2020-2025 Dietary Guidelines for Americans recommend consumers get 45% to 65% of total calories from carbohydrates. With a low-carb diet, the percentage of your calories from carbohydrates is lower than what is normally advised for individuals. Usually, on a low-carb diet, one would get about 25% of their caloric intake from carbs, Heimowitz says.
[SEE: 7 Habits for a Long, Healthy Life.]
How to Calculate Net Carbs
Figuring out your net carb intake requires doing a little bit of math, Groat says. A food label may tell you the total number of carbs in a package of nuts or a serving of broccoli, both of which are foods you can eat on a keto or low-carb diet. But the labels won’t tell you the number of net carbs. That’s because net carbohydrates are the total grams contained in a particular food minus its grams of fiber and sugar alcohols.
Therefore, to calculate net carbs you have to deduct the grams of fiber and sugar alcohols, because they aren’t digested by the body, Heimowitz says.
You can calculate your net carb intake by:
— Reading food labels and measuring.
— Using apps.
— Using the Food and Drug Administration website on how to read food labels.
1. Reading food labels and measuring. This is the easiest way to count carbs, Groat says. For example, suppose a good contains 11 grams of carbs per 1/3 of a cup, and 4 grams of fiber. Subtract the 4 grams of fiber and you end up with 7 grams of total, or net, carbs.
2. Using apps. There are a number of free apps you can download onto your smartphone that will help you determine carbs per serving of foods that may not have labels. For example, the app CalorieKing provides this information. (Many food apps count sugar alcohols as carbs).
3. Using the USDA website. The Department of Agriculture is a great resource, Groat says. It includes helpful tips about how to read food labels, which can be confusing. The USDA website FoodData Central can also be a good resource for providing data that helps you count net carbs.
Following a Low-Carb Diet
Research suggests that adhering to a keto diet may help you drop pounds initially. For example, a study published in the journal Canadian Family Physician in 2018 concluded that “ketogenic diets can help patients lose about 2 kg (kilograms, about 4.4. pounds) more than low-fat diets do at one year, but higher-quality studies show no difference.” Difference or not, the study suggests following a keto diet is effective for weight loss.
Different low-carb diets call for varying low levels of carb consumption. The keto diet, which is rated No. 37 in U.S. News’ Best Diets rankings, calls for extreme carb restrictions — about 20 net carbs a day or less, depending on the version.
Foods you can eat on the keto diet include:
— Avocados.
— Cocoa butter.
— Instead of skinless poultry and lean cuts of meat, protein sources include ribeye steak, skin-on chicken thighs, pork roast and snacks like bacon.
— Whole-dairy foods are encouraged.
— You counter sugar cravings with desserts like dark chocolate and nut butter.
— For a salad, greens such as spinach, kale and lettuce, along with broccoli, cauliflower and cucumbers, are OK, but starchy veggies — such as corn and sweet potatoes — are too high in carbs.
— Salad dressing could consist of oils like avocado, olive, canola, flaxseed and palm, or even mayonnaise.
— Nuts (walnuts, almonds, cashews).
— Seeds (pumpkin, sunflower, flaxseed, chia seeds).
— Olives.
— Nut butters (peanut, cashew, almond butters).
— Oils (avocado, olive, MCT, sesame, flaxseed, fish and coconut oils).
— Tahini.
As there are different low-carb diets, there also various versions of the keto eating regimen, including:
— Dirty keto. You have a bit more latitude to eat what you want on the dirty keto diet, so long as you keep overall carb intake low. You can occasionally consume foods like chocolate, potato chips and processed proteins.
— Modified keto. Compared to the classic keto eating regimen, you can get a slightly lower percentage of your calories from fat and more from protein and carbs.
— Several commercial diets that incorporate keto-friendly products.
[See: 13 Best Fish: High in Omega-3s — and Environment-Friendly.]
Benefits vs. Risks of Low-Carb Eating
Some studies suggest adhering to a low carbohydrate eating plan can be helpful for people with certain conditions.
A study published in September 2021 in Nutrients states that there’s a large body of scientific literature that suggests that people with obesity, prediabetes and Type 2 diabetes are “highly responsive” to a low-carbohydrate eating regimen.
On the other hand, some research suggests that some low-carb diets may be associated with health risks. For example, research published in July 2021 in Frontiers in Nutrition suggests that very low-carb diets (which could be considered keto regimens) are associated with myriad health risks.
Those risks include:
— Pregnant women on such diets are more likely to have a child with a neural tube defect, even when supplementing folic acid.
— Increased risk of cardiovascular disease.
— Higher risk of cancer.
Other potential risks with the keto diet include:
— Nutrient deficiency.
— Constipation.
— Liver issues.
It’s helpful to keep in mind that you don’t have to be a math whiz to count net carbs, Heimowitz says. “The only math you need to do on your own is with whole foods by just subtracting fiber grams from total carbs to get to net carbs,” she says. “Products low in carbs usually do the math for you on the package, so you just need to look for the net carb call out, usually outside the nutrition facts panel and/or on front of the package, and just count the net carbs listed.”
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How to Calculate Net Carbs in Your Diet originally appeared on usnews.com
Update 04/05/22: This story was published at an earlier date and has been updated with new information.