Calories, Weight and Height According to Age

Figuring out how many calories you should eat per day is challenging. You can use time-consuming techniques to get accurate data, or use an average calorie intake for age, height and weight.

People come in all shapes and sizes. Height, weight, the amount of muscle you have, the amount of activity you do per day and your gender all factor into ​how many calories you need​. Weight can also fluctuate throughout your life. You might gain weight early on and then lose it, or gain weight later in life. Height, however, stays fairly constant as you age.

The average weight and height of people in the United States is gathered to an extent by the Centers for Disease Control and Prevention, or CDC. You might remember your doctor taking your height and weight as a child, then showing you a chart of average height and weight for your age. Those statistics help doctors chart your growth, but there are also averages for adults.

According to the CDC, the average height for men 20 and over is 69 inches, which is equivalent to ​5 feet and 9 inches tall​. The average weight for men over 20 is 197.3, and the average waist circumference is 40.3 inches. The numbers for these averages were collected between 1999 to 2000 and 2015 to 2016.

For females over age 20, the average height is 63.6 inches. That comes out to about ​5 feet and 3.6 inches tall​. The average weight is 170.5, and the average waist circumference is 38.7 inches.

The CDC notes that the average weight, waist circumference and body mass index has increased over time. Body mass index, or BMI, is your bodyweight in kilograms divided by the square of your height in meters according to an article from the CDC. It's an easy way for the government to track average size of a large population because it's easy to calculate.

If you're over age 20, there's a BMI scale to determine if your weight status:

• BMI below 18.5 = underweight
• 18.5 to 24.9 = healthy weight
• 25 to 29.9 = overweight
• 30 and above = obesity

However, these are just general numbers. BMI doesn't take into account how muscular someone is, so if you have plenty of muscle mass you might not have overweight or obesity.

​Read more:​ The Average Height and Weight by Age

According to the Office of Disease Prevention and Health Promotion, there's a range of calorie consumption for gender, age and height. Activity level is also an important factor. Keep in mind that these are only estimates, and your specific needs may be outside of these generalizations.

These ​calorie requirements​ are based on a 5 foot, 10 inch individual weighing 154 pounds for men and a 5 foot, 4 inch tall individual weighing 126 pounds for women.

For men, the average calorie recommendations for teenagers aged 16 to 18 are:

• 2,400 calories for sedentary individuals
• 2,800 calories for moderately active individuals
• 3,200 calories for active individuals

For females in the same age category, the calorie recommendations are:

• 1,800 calories for sedentary individuals
• 2,000 calories for moderately active individuals
• 2,400 calories for active individuals

For males aged 19 to 20, the recommendations are:

• 2,600 calories for sedentary individuals
• 2,800 calories for moderately active individuals
• 3,000 calories for active individuals

For females aged 19 to 20 the recommendations are:

• 2,000 calories for sedentary individuals
• 2,200 calories for moderately active individuals
• 2,400 calories for active individuals

For males aged 21 to 25 the recommendations are:

• 2,400 calories for sedentary individuals
• 2,800 calories for moderately active individuals
• 3,000 calories for active individuals

The average calorie recommendation for an adult stays fairly consistent throughout the 20s and 30s, but calorie needs slowly decrease as you age from a decrease in ​basal metabolic rate​, according to the Office of Disease Prevention and Health Promotion.

For example, by age 61, the average recommended intake for men is:

• 2,000 calories for sedentary individuals
• 2,400 calories for moderately active individuals
• 2,600 calories for active individuals

For women of the same age, the recommendations drop to:

• 1,600 calories for sedentary individuals
• 1,800 calories for moderately active individuals
• 2,000 calories for active individuals

The activity levels they use are according to the following:

• Sedentary individuals don't do any physical activity outside of daily tasks.
• Moderately active individuals do physical activity that equals 1.5 to 3 miles of walking at 3 to 4 miles per hour.
• Active individuals do activity that equals over 3 miles of walking at 3 to 4 miles per hour.

These recommendations work well if you fit into the average categories of activity, height and weight. However, if you don't, you should look for something more specific.

​Read more:​ Recommended Caloric Intake for Weight Loss

If you're trying to lose, maintain or even gain weight, it's useful to know how many calories per day you should eat. No matter what your goal is in terms of bodyweight, your calorie consumption plays a part. Weight gain and weight loss is determined by the ​number of calories you eat​ versus the number of calories you burn.

To gain weight you need to eat more calories than you burn, which is called a positive energy balance. To lose weight you need to be in a negative energy balance, meaning you burn more calories than you take in, according to a November 2017 study published in Endocrinology and Metabolism. Figuring out how many calories you burn and how many you eat can be complicated.

Tracking your food takes some time and there's a learning curve, but it's an effective way to track your calorie intake. Download an app and start logging everything you eat.

Figuring out how many calories you burn can be a little more difficult. There are a lot of factors that go into that equation. Your resting metabolic rate is the number of calories you burn independent of activity, and is slightly different for everyone according to an article from ACE Fitness.

The number of calories you burn in a workout depends on factors like your size and the intensity of the workout. Some heart rate monitors track ​calories burned in a workout​, although these might not be entirely accurate. You can also use a calculator from the Hospital for Special Surgery to measure the caloric expenditure of certain exercises.

Much harder to measure is the number of calories you burn every day from non-exercise activity thermogenesis, which is activity like cleaning dishes or doing laundry that counts as activity but not exercise.

It's easier to use an online calorie intake calculator, which gives you a general idea of how many calories you should eat per day. Even though it might not be completely accurate, it's still more accurate than a ​generalized recommendation​ for your age that doesn't take into account your height and weight.