Here’s How Many Carbohydrates You Really Need in a Day

Plus, if you're trying to translate the meaning of your nutrition labels, here's how many calories are inside one gram of carbohydrates.

A diet is highly personal. One person might feel healthiest when they’re regularly enjoying the benefits of sweet potatoes, whole grain bread and brown rice…while another feels best with clean, lean proteins and vegetables. Some modern diets, like Atkins and the ketogenic (keto) diet, promote weight loss by limiting carbohydrates, which can shift the physiology into a state of “ketogenesis”—a period when the body uses fat as a source of energy, instead of carbs.

Most licensed nutrition experts will flag a warning about going to any extreme with nutrition. The buzz around limiting carbohydrates, in particular, concerns some because when you remove foods like grains, you’re also taking away one of the body’s main sources of energy…and some solid nutrients. When that becomes problematic, signs you’re not  eating enough carbs can include headaches, constipation, fatigue, poor athletic performance, and more.

So how many grams of carbohydrates do you really need in a day? We looked to a few key sources for the answer.

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What are carbohydrates?

“Carbohydrates are the body’s primary source of energy,” says registered dietitian Maggie Michalczyk, RDN, who also describes carbohydrates as “the primary fuel for the brain and cells.” This nutrition expert continues: “It is essential to have adequate amounts of carbs for maintaining mental clarity, alertness, and many other critical body functions, including proper digestion, immunity, energy, and growth.”

The United States Department of Agriculture’s Dietary Guidelines for Americans recommends that up to 45% to 65% of your daily calories should come from carbohydrates. To figure out how exactly that percentage adds up in terms of what you eat in a day, keep in mind that caloric intake will vary person-to-person—but, for an average 2,000-calorie diet, this would equate to around 900 to 1,300 calories a day coming from carbohydrates.

One gram of carbohydrates contains four calories, so if you’re counting your macronutrients, that would equal somewhere between 225 and 325 grams of carbohydrates per day. However, this isn’t a red light to eat a massive serving of pasta. According to Michalczyk, your carb intake should have a major focus on complex carbohydrates.

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What are complex carbohydrates?

You’ve probably heard there are different types of carbohydrates: Simple carbs, and complex carbs. Here’s a refresher on which carbs are “good,” and which you should consider more occasional treats.

“Simple carbohydrates are more refined and processed, making them less nutrient-dense,” Michalczyk says. Foods with simple carbs include like white pasta, bread, and packaged snack foods. “They are referred to as ‘simple’ because they are easily digested and absorbed, which can also elevate your blood sugar faster, causing a spike and crash.”

Complex carbs, on the other hand, help to slow down the blood sugar spike and help you feel fuller for longer. “Complex carbohydrates provide more sustainable energy and nutrients,” Michalczyk explains. “They also contain fiber, which helps them to be digested slower, preventing a spike in our blood sugar.”

Michalczyk suggests eating enough fiber can easily be achieved if you’re adding more sources of complex carbohydrates into your diet. Get more specifics: Here’s How Much Fiber You Really Need in a Day

What are net carbs?

Because fiber is an indigestible carbohydrate, it doesn’t really break down in your system. Instead, fiber moves through your system, while simultaneously benefiting your gut health, digestive health, and colon health.

This means that complex carbohydrates, which tend to have a high amount of dietary fiber, would also have a total net carb count. Net carbs are the total amount of carbs you consume when you subtract the grams of fiber from the overall carbohydrate count. For example, if a slice of whole-grain bread has 20 grams of carbs but five grams of fiber, that would mean the net carb count is 15 grams for that slice.

If you’re getting enough fiber in the diet, your net carb count is something that typically shouldn’t be a concern. Net carb count tends to be important for low-carb diets, like keto—which allows a conservative 20 grams of net carbs per day or less. Any diet with less than 130 grams of carbohydrates (or less than 26% of your daily calories) would be considered “low-carb.”

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What types of foods contain complex carbs?

If you’re looking to add healthy sources of complex carbs into your diet, Michalczyk shared a list:

  • Whole grains: Brown rice, quinoa, whole wheat breads, and oats
  • Legumes: lentils, chickpeas, black beans, peas
  • Vegetables: sweet potatoes, squash, broccoli
  • Fruits: apples, bananas, and berries
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Medically reviewed by Latoya Julce RN, BSN, on May 04, 2023

Kiersten Hickman
Kiersten Hickman is a journalist and content strategist with a main focus on nutrition, health, and wellness coverage. She holds an MA in Journalism from DePaul University and a Nutrition Science certificate from Stanford Medicine. Her work has been featured in publications including Taste of Home, Reader's Digest, Bustle, Buzzfeed, INSIDER, MSN, Eat This, Not That!, and more.