How many calories should I eat?
There is no single number. The Dietary Guidelines for Americans lay out 12 calorie levels for ages 2 and older, running from 1,000 to 3,200 calories a day, because needs vary with age, sex, body size, and activity. To get an estimate for yourself rather than a population average, use the NIH Body Weight Planner or the DRI Calculator.
Where does the 2,000-calorie figure come from?
It is the reference value used to calculate the percent Daily Values printed on Nutrition Facts labels, chosen so labels have a consistent basis. It was never meant as a personal target. Many adults need meaningfully more or less.
What is a calorie deficit?
A calorie deficit means taking in less energy than you use, so the body draws on stored energy. The conventional estimate is that about 3,500 calories corresponds to roughly one pound of body fat, which is why a deficit of about 500 calories a day is often described as producing about one pound a week. It is a useful approximation, not a precise law: energy expenditure adapts as you lose weight, which is why loss usually slows over time.
How fast should I lose weight?
The CDC's guidance is gradual and steady, about 1 to 2 pounds a week, and notes that people who lose weight at that pace are more likely to keep it off than those who lose faster. Very low intakes are harder to sustain and make it harder to meet nutrient needs.
What are BMR and TDEE?
Basal metabolic rate is the energy your body uses at complete rest to run basic functions, and it is the largest share of daily expenditure for most people. Total daily energy expenditure adds the energy used for digestion, daily movement, and deliberate exercise. Online calculators estimate both from equations; they are starting points to adjust from, not measurements.
Do calories from different foods count the same?
For energy accounting they are broadly comparable, but the foods behave differently. Protein and fiber increase fullness and protein costs more energy to digest, so the same calorie total can leave you more or less hungry depending on composition. Calorie quality also determines whether you meet nutrient needs while eating less.
Are the calorie counts on labels and apps accurate?
They are estimates with real margins of error. Manufacturer labels are permitted a tolerance, restaurant figures are calculated from standard recipes rather than the plate in front of you, and crowd-sourced app databases contain user-entered errors. Use them for consistent relative tracking rather than treating any single number as exact.
Should I eat back the calories I burn exercising?
Wearables and cardio machines commonly overestimate calories burned, sometimes substantially, so eating back the full displayed amount can erase a deficit. A common approach is to plan intake around your overall activity level rather than adjusting meal-by-meal for each workout.
Why has my weight loss stalled?
Two ordinary explanations cover most stalls. Energy expenditure falls as body mass falls, so the deficit that worked at the start is smaller now. And portion estimates drift upward over weeks without anyone noticing. Day-to-day scale movement also reflects water, sodium, and digestive contents, so a flat week is not necessarily a stall at all.
What do the current Dietary Guidelines recommend?
The 2025-2030 Dietary Guidelines for Americans were released on January 7, 2026 by USDA and HHS. The core message is to eat real food: prioritize whole, minimally processed foods, high-quality protein, healthy fats, fruits, vegetables, and whole grains, and limit ultra-processed foods, added sugars, and refined carbohydrates. The edition is much shorter than previous ones and is published at realfood.gov.