How Many Calories Should I Eat In A Day?

Not everyone needs 2,000 or 2,500 calories a day, as most health experts recommend. Your daily calorie intake depends on lots of different factors, from your weight to your health and training goals. 

According to the 2015-2020 Dietary Guidelines for Americans, adult men should aim for 2,000 to 3,000 calories per day. Women, on the other hand, should get about 1,600 to 2,000 calories. As you might have guessed, the low end of this range is for those with a sedentary lifestyle. 

These estimates, though, apply to the general population. Athletes have different nutritional needs than the average person. Most studies are conflicting, so it’s perfectly normal to ask yourself “How many calories should I eat a day?” 

Competitive bodybuilders, for example, have higher protein requirements compared to recreational lifters. The same goes for their energy intake. Building mass takes energy, so you can’t live on salads and protein bars. 

However, this doesn’t mean that smashing thousands of calories from cookies and junk food each day is the key to muscle growth. While it’s true that calories matter, food quality and composition are even more important. 

Laying the foundation for a well-rounded diet can be challenging — and that’s what we’ll discuss today. Here’s what you should about the calories in food and how to determine your energy intake! 

Where Do Calories Come From? 

All food packaging lists the number of calories, which are units of energy. Think of calories as the energy you get from the foods and beverages consumed. These nutrients fuel every cell in your body and come from four sources:

• Protein — 4 calories per gram
• Carbs — 4 calories per gram
• Fats — 9 calories per gram
• Alcohol — 7 calories per gram

Protein, fats, and carbs are called macronutrients. Vitamins, minerals, and other micronutrients, by contrast, provide zero calories. 

Alcohol does supply calories, but it’s not considered a macronutrient because your body doesn’t need it for survival. 

Not all calories are created equal, though. A 400-calorie serving of steak has a completely different nutritional value than a bag of potato chips with the same number of calories. See it for yourself:

Grilled Beef Tenderloin Steak — 7 ounces 

• 400 calories
• 72 grams of protein
• 16.8 grams of fat
• 40% of the DV (daily value) of iron
• 46% of the DV of phosphorus
• 17% of the DV of potassium
• 86% of the DV of zinc 
• 385% of the DV of vitamin B12 

Potato Chips — 2.5 ounces 

• 400 calories
• 4.8 grams of protein
• 25.3 grams of fat
• 38.2 grams of carbs
• 6% of the DV of iron
• 8% of the DV of phosphorus
• 20% of the DV of potassium
• 10% of the DV of zinc

Calorie per calorie, and as expected, steak is more nutritious than potato chips and other processed foods. 

Sure, you don’t have to eat 7 ounces of steak at once, but even half of that amount has more protein, vitamins, and minerals than what you’d get from potato chips. 

Do Calories Matter?

As mentioned earlier, calories are essential for survival. However, they’re only a small part of the picture. As an athlete, you should rather focus on protein, carbs, and fats — the three macros. 

Counting calories isn’t really necessary, but it’s good to set some limits based on your training goals. 

Muscle growth, or hypertrophy, requires a caloric surplus. For best results, increase your energy intake by 360 to 480 calories per day. Track your progress and adjust your diet accordingly. 

It’s uncommon to see bodybuilders who eat 5,000 or more calories a day when bulking up. This approach isn’t necessarily wrong, but it makes things more difficult once you start cutting. The higher your calorie intake in the off-season, the more weight you’ll gain. 

According to a review published in the International Journal of Exercise Science, there’s a big difference in protein versus carbohydrate and/or fat overfeeding in relation to body composition. 

A high-protein, high-calorie diet is less likely to increase fat mass and body weight compared to a high-carbohydrate or high-fat diet that exceeds your energy needs. 

Several studies cited in the above review have found that high-protein, high-calorie diets can actually prevent or minimize fat gain. 

What about Genetics?

Furthermore, genetics may influence the changes in body composition during overfeeding. This factor affects fat distribution as well as the amount of fat mass accumulated.

These findings confirm that macronutrient ratios matter most. Therefore, if you’re planning to bulk up, fill up on protein rather than carbs or fats. 

Weight loss, on the other hand, requires a caloric deficit, meaning that you need to take in fewer calories than you burn. 

Again, focus on dialing in your macros. Protein facilitates fat loss through several mechanisms:

• Suppressing appetite and promotes satiety
• Help preserve lean mass and keeps your metabolism up
• It has a higher thermic effect than fats and carbs 
• When combined with resistance training, it may help improve body composition

The Truth about “Calories in vs. Calories Out”

Whether you want to lose or gain weight, you must be wondering how many calories you need to reach your goal. 

As you might have heard, reducing your energy intake by 500 calories a day should lead to a one-pound weight loss per week. This makes sense, considering that each pound of fat equals 3,500 calories. 

Unfortunately, it’s not that simple. Your metabolism is highly adaptive and begins to slow down as you reduce your calorie intake. You may lose one pound per week for a month or so, but you’ll hit a plateau at some point. 

Depending on your energy intake, you might be able to break the plateau by further cutting calories. However, you can’t use this strategy each time your weight stagnates. Eating too little for long periods of time may lead to metabolic damage and make it even harder to torch fat. 

Additionally, severe or prolonged energy restriction is often accompanied by hormonal imbalances, diminished performance, and reduced mitochondrial efficiency, according to the Journal of the International Society of Sports Nutrition (JISSN). These negative outcomes are due to metabolic adaptation. 

Fitness models, bodybuilders, and other athletes resort to periodic refeeding or reverse dieting to counteract these changes. These practices require increasing caloric intake above maintenance levels after dieting for a long time. 

For example, some athletes incorporate 24-hour refeeds once or two twice weekly to replenish their glycogen stores and prevent metabolic slowdown. 

As the JISSN points out, weight regain is common after the cessation of a restrictive diet. For this reason, many athletes find it hard to get back in shape once the competitive season is over. 

How to Break Through a Weight Loss Plateau

You do need to lower your calorie intake to lose fat. However, your metabolism will eventually adapt to these changes in energy intake and slow down, leading to a weight loss plateau. 

Use these strategies to keep burning fat and prevent metabolic damage: 

• Increase protein for satiety & muscle development
• Reduce your energy intake gradually rather than making drastic changes 
• Incorporate high-intensity interval training (HIIT) into your workouts
• Increase exercise intensity or frequency
• Cut down on carbs
• Consider a temporary cycle of low-carb or ketogenic diet
• Try intermittent fasting 
• Get plenty of sleep and limit stress
• Reassess your caloric needs
• Incorporate refeeds into your diet or try carb cycling
• Lift heavier and emphasize compound movements

Let’s take HIIT, for example. Compared to steady-state cardio, this training method yields better results in less time. Check out our guide to HIIT vs. cardio to see the difference between the two! 

A recent study published in the Journal of Exercise Rehabilitation assessed the effects of HIIT on body composition without caloric restriction. The HIIT group experienced a major reduction in fat mass as well as improvements in blood lipids, maximum oxygen uptake (VO2 max), and fat-to-muscle ratio in just 12 weeks. 

Other studies show that high-intensity interval training may help reduce visceral fat, or belly fat, improve cardiorespiratory fitness, and decrease waist circumference.

Another strategy you can use to break through plateaus is to cut down on carbs. Better yet, switch to a ketogenic diet to get your body into fat-burning mode. Try these keto shortcuts to speed up fat loss and boost your metabolism!

If everything fails, go on a reverse diet. Simply increase your calorie intake for a couple of weeks. You may gain a few pounds, but you’ll get better results once you start cutting.

How Many Calories Should I Eat a Day? Key Factors to Consider

Now let’s return to your question — How many calories should I eat a day? First of all, you need to define your goals. As discussed earlier, weight loss requires an energy deficit, while hypertrophy requires an energy surplus. 

Your daily calorie intake depends on three main factors:

• Basal metabolic rate
• Activity level
• Digestion 

Basal metabolic rate (BMR) is the amount of energy or the number of calories, you burn at rest.

This is how much energy your body uses for digestion, breathing, and other vital functions. It depends on a multitude of factors, including your age, gender, nutritional status, altitude, climate, and more. 

There are several online calculators that may help determine your basal metabolic rate. These estimates are not 100% accurate, but you can use them as a starting point. 

Real World Example

A 30-year-old man who weighs 180 pounds and is 5′9″, for instance, has a BMR of approximately 1,860, according to Active.com. This is the number of calories he burns at rest. However, his energy expenditure also depends on body composition, overall health, climate, and so on. 

You must also consider your activity level. The more active you are, the higher your energy expenditure. 

What you eat matters too. Your body uses about 5 to 15% of calorie intake to break down and digest food. This process is called diet-induced thermogenesis. 

Protein, for example, requires more energy to digest than carbohydrates and dietary fats. Therefore, you’ll burn more calories when eating high-protein foods than high-carb or high-fat foods. 

Estimate Your Energy Requirements

Feeling confused? You’re not alone. Unless you have access to state-of-art equipment, it’s hard to estimate your energy needs on your own. 

The Dietary Guidelines provide some estimates by age, sex, and activity level. If, let’s say, you’re a 30-year-old man with an active lifestyle, you should strive for about 3,000 calories per day to maintain your weight. 

The best thing you can do is to determine your current calorie intake and BMR — and then adjust your diet based on your goals, whether it’s hypertrophy, fat loss, or weight maintenance. 

Reduce your energy intake by 250 to 500 calories a day to get leaner, or increase it by 360 to 480 calories per day to build mass. Adjust these numbers based on your progress. 

For example, if your diet provides around 2,500 calories, strive for 2,000 to 2,250 calories per day to lose fat or 2,860 to 2,980 calories a day to gain muscle. 

But there’s a more accurate way to find out how many calories you need. And this brings to the next point:

Calculate and Track Your Macros

As mentioned earlier, each macronutrient provides a specific number of calories. Therefore, you can estimate your energy intake based on the amount of protein, carbs, and fats in your diet. 

The JISSN, for example, recommends athletes to consume 1.4 to 2 grams of protein per kilogram of body weight per day, spread evenly across their meals. Each gram of protein supplies 4 calories, meaning that a 180-pound man should get 1,000 to 1,440 calories per day from protein alone. 

Next, increase or reduce your daily intake of carbs or fats based on your goals. 

So if you must lower your energy intake to 2,000 calories a day to get leaner, subtract at least 1,000 calories worth of protein. The remaining 1,000 calories may come from either carbs (4 calories per gram) or fats (9 calories per gram). 

Experiment with different macronutrient ratios and see how your body reacts. Read our guide to the IIFYM (If It Fits Your Macros) diet to find out how to dial in macros. Or use these tips to calculate your macros according to your training goals. 

Your Needs

Before doing the math, consider your activity level, workout intensity, and body composition. Endurance athletes or powerlifters, for instance, need more carbs than the average bodybuilder. While it’s true that cutting back on carbs can help you get leaner, low-carb diets are not for everyone.

A research paper featured in the journal Sports analyzed the strategies elite bodybuilders use to achieve a lean, muscular physique. 

As the scientists point out, these athletes gradually reduce their fat and carbohydrate intake to lose fat and create an energy deficit. Yet, their protein intake remains similar to the off-season in order to preserve lean mass.

Carbohydrate intake is timed around exercise, especially before, during, and after training. 

Interested to find out more? Here’s what a typical old school bodybuilding diet looks like. 

Get the Most Nutritional Bang for Your Buck

We hope our guide answers your question, “How many calories should I eat?” As you see, there’s no set number of calories to consume for fat loss or muscle building. It all comes down to your individual needs. 

Regardless of your training goals, pay attention to where your calories come from. The source of calories has a direct impact on your metabolism and body composition. Even when bulking up, you should still eat clean and make smart food choices. 

Remember, calories are not everything. In theory, you can lose weight by eating potato chips at every meal as long as you stick to your calorie budget. 

These snacks, though, are chock-full of trans fats, added sugars, and chemicals that can mess up your hormones and throw your appetite out of control.

Not to mention that a diet based largely on junk food may put you at risk for heart disease, diabetes, metabolic syndrome, and premature death. 

Get your calories from whole foods. Fatty fish, lean meat, leafy greens, legumes, fresh fruits, nuts, and seeds should come first on your list. Feel free to have a cheat meal every now and then, but don’t make a habit out of it. 

How do you track your energy intake? Do you count calories or macros or stick to a specific diet? Share your thoughts in the comments section below!