EVEN AS NEW, trendy diets emerge, calorie counting remains a reliable practice in the world of weight loss.
According to the International Food Information Council’s 2024 Food and Health Survey, 54 percent of Americans said they followed some kind of diet or new eating pattern in the past year. Of those people, 13 percent choose calorie counting.
“It can be helpful to gain a little insight into your diet and help people reach weight-loss or performance goals,” especially if it’s done on a short-term basis, says Tara Tomaino, R.D., director of nutrition at The Park.
While you don’t necessarily need to count every calorie to stay healthy, it helps to have a basic understanding of how your body uses energy gained from food. Here’s an overview of what calories are, what influences your energy needs, and how to estimate how many calories you need.
What is a calorie?
Kilocalories (kcal)—which we simply refer to as calories—are the amount of heat needed to boost the temperature of 1 kilogram of water by one degree Celsius, according to the U.S. Department of Agriculture (USDA).
So, calories are a measure of energy, which we need to function. We need calories to move around and carry out the basic body functions that happen when we’re at rest, from DNA synthesis to hormone production to sending chemical messengers throughout the body in order to keep things running smoothly.
The three macronutrients—fat, carbs, and protein—contain a set number of calories per gram, according to the USDA. Carbs and protein have 4 calories per gram, and fat has 9.
What’s the minimum calorie intake for men per day?
Men typically need between 2,000 and 3,000 calories a day, according to the Dietary Guidelines for Americans. But, your minimum (and maximum) calorie intake depends on several factors, including your height, weight, activity level, and age, Tomaino says.
“For a small man, I wouldn’t want them to eat less than 1,500 calories,” she says. “And, that would be for an individual looking for weight loss.”
If you’re not trying to lose weight, Wesley McWhorter, Dr.PH., R.D.N., L.D., C.S.C.S., spokesperson for the Academy of Nutrition and Dietetics suggests sticking to around 2,500 calories a day.
How many calories do men need to eat?
“The primary factors that determine how many calories someone needs include birth sex, age, genetics, body size, and daily activity level,” says Anya Rosen, M.S., R.D., a New York-based dietitian. “Other variables can play a significant role, such as body composition, dieting behaviors, injury, or illness.”
In general, men burn more calories than women because they’re typically larger overall. Men are also predisposed to having more muscle and less fat mass, which impacts calorie burn, explains Kyle Gonzalez, M.S., C.E.S., C.S.C.S., an exercise scientist.
Per the Centers for Disease Control and Prevention (CDC), the average American man under 40 is 5 foot 9 and weighs 197 pounds. At a moderate activity level (moderate exercise 3 to 5 times per week), he would need about 2,822 calories per day to maintain his weight.
To Lose Weight
Cutting 500 to 1,000 calories out of your day can help you safely lose one to two pounds a week. For the average guy, that’s between 1,822 and 2,322 calories per day.
When you drastically cut calories, it can backfire, as you may end up getting so hungry that you overeat.
It’s also important to factor in exercise: If you’re burning 500 calories a day through physical activity, cutting 1,000 calories would actually lead to a deficit of 1,500 calories, which is too much.
To Gain Weight
If you want to gain weight, the Cleveland Clinic recommends increasing your calorie intake by 300 to 500 calories a day—3,122 to 3,322 calories per day for the average guy, assuming his activity level stays the same.
Injury and illness can also temporarily increase the amount of calories you need.
Certain injuries or illnesses can mean you need extra calories. Healing from burns or large open wounds requires extra energy and protein. If you have a fever, you need more calories to make up for your higher body temperature. Even fighting off the common cold takes energy.
How many calories should you eat per meal?
Evenly spacing your calories during the day is the best approach.
Tomaino suggests eating three meals and two snacks a day, and divvying up your total calories for the day across your meals.
“If you’re having those three meals, they could be between 500 and 700 calories, depending on what the total calorie goal is at the end of the day, and then make up the remainder with those snacks in between,” she says.
But, it’s really a personal preference. Some people prefer eating a larger breakfast and smaller dinner, so being mindful about what works for you is the best approach, McWhorter says.
Does calorie intake for men change with age?
Yes. Once you turn 60, you need 2,000 calories a day if you’re sedentary and between 2,200 and 2,600 if you’re moderately active or active.
That’s slightly less than what you need earlier in life. Between ages 21 and 40, men need 2,400 calories a day if they’re sedentary, 2,800 to 2,600 if they’re moderately active, and 2,800 to 3,000 if they’re active.
In your 40s and 50s, you need 2,200 if you’re sedentary, 2,400 to 2,600 if you’re moderately active, and 2,600 to 2,800 if you’re active.
“Your metabolism is pretty much steady throughout most of adulthood,” Tomaino says. “Once you reach about age 60, your muscle mass is decreasing and the general aging of your cells slows down your metabolism in such a way that you don’t need as many calories.”
How to Calculate Your Calorie Needs
Although it’s possible to estimate how many calories you need in a day, there’s one huge caveat: “There are many different formulas available to determine calorie needs, but they all have large margins of error due to there being too many influential variables to control,” Rosen says.
Scientists use a method called indirect calorimetry to measure exactly how many calories a person burns in a day, but it’s expensive, time-consuming, and pretty inaccessible for most people.
If you’re curious about your exact calorie needs, here’s how to determine it.
Track Your Food Intake
“I find that the best way for you to determine your calorie needs (assuming you’re outside of a research setting) starts with ensuring that you are currently maintaining your weight,” Rosen says.
“Once weight is stable, track your food intake for one to two weeks without changing how you would normally eat,” she says. “The average calories across that time frame is a good estimate for your maintenance caloric needs, and you can adjust from there according to your goals.”
In other words: If your weight isn’t changing, you’re eating the right number of calories.
Using an app, like My Macros+, helps you count calories while focusing on your protein, carbs, and fat intake, Tomaino says. “If someone’s goal is to build muscle or to maintain muscle while losing body fat, it’s really important to know where those calories come from because plenty of foods can be equal in calories, but not nutrition.”
MyFitnessPal also lets you easily track calories, because you can scan barcodes on food packages or use its food database, she adds.
Use a Metabolism Calculator
You can also try using a formula to estimate your calorie needs, which is easy to do with an online calorie calculator from a trusted source. This one, from the American Council on Exercise, takes into account your age, weight, gender, height, and activity level, from sedentary to very active to determine your calorie needs.
How does muscle mass affect calorie burn?
Muscle burns more calories by weight than body fat, although the difference isn’t as big as it’s sometimes made out to be. “The claim ‘muscle burns more calories than fat’ is true, but misleading,” Rosen says.
The best estimate is that a pound of muscle burns six to seven calories a day. Fat burns about two calories in the same time period.
So, increasing muscle will increase the number of calories you burn — as will gaining fat, though to a lesser degree — but not drastically. An extra 10 pounds of muscle may only add 60 calories per day to your overall calorie expenditure.
The size of other body parts probably plays a more significant role in your daily calorie needs. A 2011 study found that more than 40 percent of differences in total calorie burn between people could be explained by the variations in the size of their internal organs.
How does exercise affect calorie burn?
Your activity level plays a big role in your energy needs. It’s not just your workouts that burn calories, it’s also how much you move around during the day.
A physically demanding job burns far more calories than one where you’re sitting at a desk most of the day. Biking or walking instead of driving can make a big difference, as well. When determining your physical activity level, it’s important to take all of this into account.
You also need to factor in your workouts. “With cardio training, you tend to not only burn calories quicker, but you also burn more total calories per session,” Gonzalez says. “Strength training, on the other hand, is usually anaerobic (without oxygen) in nature and helps you build muscle and boost your metabolism.”
You’ll burn fewer calories per strength-training session, he explains, but your metabolic rate (the number of calories burned) will remain elevated for longer afterward. Plus, you’ll build muscle mass, which slightly increases your calorie burn and can support better health overall.
“A healthy mixture of both strength and cardio training with varying intensity, frequency, duration, and type is always best when building out your exercise program,” Gonzalez says.
Do you need to count calories?
Ultimately, there’s no need to count calories in order to be healthy.
“Calorie counting focuses people on numbers that don’t always have a correlation with the quality of food on the plate,” says McWhorter. “When we think of calories, it’s simply a measure of energy. That’s not equal to nutrition. Nutrition is much more than just energy.”
Essentially, eating a 200-calorie bag of potato chips for snack will not have the same benefits as eating a 200-calorie piece of grilled chicken breast. The chicken has protein and will help you remain fuller for longer while the chips just are fried and a source of processed food and fat.. “Calories are not created equal,” McWhorter says.
If you feel good and have consistent energy levels throughout the day, you probably don’t need to worry about calculating your calorie needs, because chances are you’re hitting your target.
But if you’re worried that you’re eating too few or too many calories, understanding what contributes to calorie burn can help you understand your body’s needs.
Just don’t get too caught up in the numbers, McWhorter says. “There’s nothing wrong with counting calories, as long as you focus on the quality of the food. What makes up the plate? It’s not just calories; it’s food.”
Making sure half your plate is fruits and vegetables, and the other half is whole grains and protein should be your goal, he adds.
Calorie counting isn’t a good idea for anyone with a history of eating disorders, Tomaino says. And, if you’re dealing with a medical condition, check with your doctor before calorie counting, and they can refer you to a dietitian to help you get it right.
