Average Calories per Day: What Adults Eat and Burn

Average calories per day is really two numbers: what people report eating and what they burn. US men report eating 2,330 kcal a day and women 1,760 kcal, while the average adult burns about 2,437 kcal. The eating figures come from the latest federal survey, run from 2021 to 2023, and the burning figure from the NASEM 2023 dataset. Under-reporting explains much of the gap: people forget food, and that is why the eating averages look low next to the burning one.

What is the average number of calories per day?

It depends on the country, the age band and how the survey asked. The US numbers rest on a single day of recall at the interview for the 2021 to 2023 USDA survey, which covers adults 20 and over. The other three markets publish their own surveys, and I converted kilojoules to kcal where needed.

Country and survey	Adults covered	Men (kcal a day)	Women (kcal a day)	Reported shortfall
US, NHANES 2021–2023	20 and over	2,330	1,760	12–14% men, 16–20% women (OPEN study, 1999–2000)
UK, NDNS 2019–2023	19 to 64	1,883	1,491	around 30% overall (NDNS)
Australia, 2011–12 survey	31 to 50	2,443	1,802	up to 17% men, 21% women (ABS estimate)

The UK row comes from the NDNS report, published in June 2025. The ABS reports 10,220 kJ for Australian men aged 31 to 50 and 7,540 kJ for women, and dividing by 4.184 gives the kcal shown. The Canadian release I read does not split by sex. Statistics Canada gives 1,978 kcal for adults aged 19 to 50 and 1,762 kcal from age 51. The age bands differ, so compare along a row, not down a column.

Two official reference figures come with them. The NHS guide says an average man needs 2,500 kcal a day and an average woman 2,000 kcal. On US food labels, 2,000 calories a day is a general guide for nutrition advice.

Men sit 330 kcal above that label figure and women 240 below. That puts the two groups 570 kcal apart. One national figure hides all of it. This gap is why how many calories a man should eat gets its own answer.

How many calories does the average adult burn a day?

About 2,437 kcal, with a standard deviation of 592 kcal. That is the mean total energy expenditure in the NASEM 2023 dataset, measured with doubly labeled water in 5,456 adults aged 19 and over. About 66% were women, the mean age was 52.6 and the studies came from high-income countries.

Basal metabolic rate, the energy of complete rest, averaged 1,487 kcal in the 2,364 adults who had it measured, which is roughly 61% of the day’s burn, and movement, digestion and everything else the body does make up the other 39%.

A pooled average blends men and women, and you are one of them rather than the blend. To see how far apart real people sit, I ran two adults through the NASEM equation. Both are 35 and low active.

Person	Height and weight	Maintenance calories (kcal a day)
Woman	165 cm, 55 kg	2,087
Man	178 cm, 90 kg	3,024

That is a gap of 937 kcal between two ordinary adults. No average shows it. Your own number comes from the equation, then from your weigh-ins.

Why do the average calories eaten and burned not match?

Because surveys run on memory. People are asked to recall what they ate, and recall loses energy. The OPEN study checked 24-hour recalls against doubly labeled water in 484 adults aged 40 to 69. Men underreported energy intake by 12 to 14% and women by 16 to 20%.

The UK survey measured it too. A doubly labeled water sub-study from 2019 to 2022 found intake underreported by around 30% on average. The NDNS authors call this common to all dietary surveys. Australian statisticians took a different route. They estimate that reported intake may be understated by as much as 17% for men and 21% for women.

Here’s my rough correction. Reported intake is the true intake minus the missing share, so true intake is the reported figure divided by one minus that share. For US men, 2,330 ÷ 0.88 to 2,330 ÷ 0.86 gives 2,648 to 2,709 kcal. For US women, 1,760 ÷ 0.84 to 1,760 ÷ 0.80 gives 2,095 to 2,200 kcal. For the UK I applied the overall 30% to both sexes.

Group	Reported (kcal a day)	Corrected, my estimate (kcal a day)
US men	2,330	2,648–2,709
US women	1,760	2,095–2,200
UK men	1,883	about 2,690
UK women	1,491	about 2,130

The OPEN adults were 40 to 69 and the survey years differ, so read these as a sense of scale, not a measurement. The corrected US figures land a little above the NHS guides of 2,500 and 2,000 kcal. I treat the raw survey means as understated.

How does the average change with age?

Reported intake falls with age, though the curves differ by sex. Men peaked in their 40s and women in their 20s.

Age (years)	Men (kcal a day)	Women (kcal a day)
20–29	2,354	1,939
30–39	2,368	1,757
40–49	2,499	1,817
50–59	2,373	1,723
60–69	2,248	1,673
70 and over	2,077	1,657

From the 40s to 70 and over, men’s reported intake fell from 2,499 to 2,077 kcal, a 17% drop. Women’s fell from 1,939 in their 20s to 1,657 kcal, which is 15%. Measured expenditure tells a related story. A 2021 Science analysis of doubly labeled water data found that expenditure adjusted for fat-free mass held steady between 20 and 60 years. It declined in older adults. Lower energy use is a likely part of the explanation. A survey alone can’t prove it. Treat it as a pattern.

Should I use the average as my target?

No. An average describes a crowd. The NASEM report shows how far one person can sit from the estimate for people like them. The standard error is 241 kcal for women and 342 kcal for men. That’s after the equation has already used age, height, weight and activity. A number borrowed from a diet plan, such as 1,000 calories a day or a 1,200-calorie plan, knows even less about you.

Work out how many calories you need per day with the equation, eat close to it for three weeks and let your weigh-ins confirm or move it. Weigh the foods you log most often. Memory is a poor scale, and recall lost 12 to 20% of the energy on average in the OPEN study.

Enter your age, height, weight and activity in the calorie calculator and set the NASEM 2023 number it returns next to these averages. It applies a safe minimum under any goal, so the result never drops below it.

Pregnancy and breastfeeding fall outside these adult averages, so your midwife or doctor sets your energy needs. A weight change with no reason behind it is also a reason to see your doctor before you change what you eat.