MacronutrientMacronutrient

Carbohydrates

Also known as Carbs, Total carbohydrate

Carbohydrates are the body's primary and preferred energy source, and the only fuel the brain and red blood cells use efficiently. The RDA is 130 g/day for adults and children, set to cover the brain's glucose needs, while the acceptable range is 45 to 65 percent of daily calories. Quality matters: whole grains, fruits, vegetables, and legumes are preferred over refined starches and added sugars.

Recommended
130
Upper limit
Not established
Type
Macronutrient
Measured in
grams/day
Intake values verified against the NIH Office of Dietary Supplements and the IOM/NASEM Dietary Reference Intakes.

Why it matters

What it does in your body

  • Provides the body's main energy source
  • Fuels the brain and red blood cells with glucose
  • Spares protein from being burned for energy
  • Supplies dietary fiber and plant compounds
  • Supports gut health through fiber and resistant starch

By age, sex, and life stage

How much you need

The carbohydrate RDA is 130 g/day for adults and children, based on the average minimum glucose the brain uses. The acceptable range is 45 to 65 percent of daily calories. Needs rise in pregnancy (175 g/day) and lactation (210 g/day).

Recommended intake across life

in grams/day
Children 1-18
130
Adults 19+
130
Pregnancy
175
Lactation
210

Bars scale to the highest recommendation shown. Where men and women differ, both values are listed.

Full reference table

Life stageMaleFemale
Children 1-18130130
Adults 19+130130
Pregnancyn/a175
Lactationn/a210

Values in grams/day. AI marks an Adequate Intake, used when there is not enough evidence for a formal recommendation.

What moves the number

What changes your needs

Activity level

Endurance athletes and highly active people need more carbohydrate to refuel glycogen stores.

Total calorie needs

Because the target is a percent of calories, gram amounts rise with a larger overall diet.

Pregnancy and lactation

Needs rise to 175 g/day in pregnancy and 210 g/day during lactation.

Blood sugar management

People managing diabetes may adjust carbohydrate amount and type with medical guidance.

Running low

Signs you might not get enough

Low energy and fatigueDifficulty concentratingKetosis and bad breath on very low intakeBreakdown of muscle for energy over time

Most at risk: Uncommon on typical diets. Seen with very low-carbohydrate or ketogenic diets, prolonged fasting, or severe food restriction.

Too much

Can you get too much?

Weight gain from excess caloriesBlood sugar spikes with refined carbohydratesHigher triglycerides with heavy added-sugar intakeCrowding out of nutrient-dense foods

Excess comes mainly from refined grains and added sugars rather than total carbohydrate. Emphasize whole, fiber-rich sources and keep added sugars under 10 percent of calories.

Where to get it

Best food sources

Brown rice, cooked, 1 cup45 g
Black beans, cooked, 1 cup41 g
Cooked oats, 1 cup28 g
Banana, 1 medium27 g
Sweet potato, 1 medium26 g
Whole wheat bread, 1 slice13 g

The bottom line

Get most of your carbohydrates from whole grains, fruits, vegetables, and legumes, aiming for 45 to 65 percent of calories, and keep refined starches and added sugars low.

Track carbohydrates automatically

Carbohydrates is one of the 92 nutrients Vora reads from a photo of your meal, so you can see where you stand without weighing or logging by hand.

Sources and method

The recommended intakes, upper limits, and food-source amounts on this page come from the primary references below. Numbers were checked against the current NIH Office of Dietary Supplements fact sheets and the Institute of Medicine (now the National Academies) Dietary Reference Intakes.

  • Institute of Medicine, Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2005)
  • Dietary Guidelines for Americans, 2020-2025

This page is for general education, not medical advice. Reference intakes are population averages for healthy people and do not replace guidance from your doctor or a registered dietitian, especially if you are pregnant, managing a health condition, or considering supplements.