How Many Calories Should You Eat to Lose Weight?
"How Many Calories Should I Eat to Lose Weight?"
As nutritional science has progressed in recent years, it's become crystal clear that energy balance (i.e. calories in vs. calories out) is the major factor in weight management [1]. Therefore, controlling calorie intake is the utmost priority on a weight-loss diet.
Of course, diligent exercise also helps tip the energy balance scale in your favor, but you don't want to rely on physical activity to maintain a calorie deficit. Many people have a habit of doing tons of cardio to "make up for" eating too many calories throughout the day, but that's not a healthy approach for sustainable weight loss. Learning to limit the number of calories you eat takes precedence over how frequently you exercise.
So, if you're wondering, "How many calories should I eat per day to lose weight?" you've come to the right place.
Why the Number of Calories You Eat Impacts Weight Loss
Losing weight ultimately boils down to burning more calories than you consume. In other words, you need to be in a calorie deficit if you're trying cut body fat. Naturally, that means balancing the number of calories you eat per day with the amount you expend through voluntary and involuntary activity.
If you eat too much or move too little, your body will be in a calorie surplus. The surfeit energy is consequently stored, so you gain weight. The inverse is true when you limit calorie intake and move more; the body lacks energy from food, so it breaks down stored complex molecules, such as lipids in body fat tissue, to harvest energy.
Hence, the interplay between the number of calories you eat and burn (i.e. energy balance) is the most important component of a diet. But how do you figure out how many calories to eat per day to lose weight? We'll walk you through the different methods you can use to determine an appropriate daily calorie intake for weight loss.
Calculating How Many Calories You Need a Day to Lose Weight
There are several ways to estimate your daily calorie needs, some of which are more practical than others. Unfortunately, the most accurate and reliable method for assessing energy expenditure, indirect calorimetry, is also the most costly and inaccessible. But the good news is predictive equations, fitness trackers, or simple trial and error can give you a good baseline estimate in much less time (and a fraction of the price, if not for free).
Predictive Equations and Online Calorie Calculators
Our Macro and Calorie Calculator uses the Mifflin-St. Jeor metabolic rate equation, which is widely regarded as the most accurate predictive equation for determining basal metabolic rate (BMR), and an advanced algorithm to help get your weight-loss journey off on the right foot. According to a recent systematic research review of studies, the Mifflin-St. Jeor equation predicted BMR within 10% of what was actually measured in obese and non-obese adults, and it also had the smallest error range [2].
Other equations, such as the Harris-Benedict equation and Owen equation, were significantly less accurate in some studies. Paradoxically, the Mifflin-St. Jeor equation requires less information than most predictive metabolic rate equations. The only variables are sex, body weight, height, and age. Body fat (and lean body mass) are not taken into account.
However, predictive equations tend to overestimate basal metabolic rate (BMR), especially in obese individuals (body mass index >30 with significant body fat) [3]. If you're a male with a body fat percentage greater than 20% or a female above 30%, odds are your true BMR will be less than what an equation projects. Keep this in mind if you use an online calorie calculator to determine your energy needs. It might be prudent to use a guesstimate of your fat-free mass as the bodyweight input.
For example, a 250-pound man with roughly 20% body fat has about 200 pounds of fat-free mass; he should use the latter as his weight when calculating calorie needs to get a more reliable estimate.
Calorie Tracker Devices
Many fitness tracking gadgets are available nowadays, such as the FitBit, Apple Watch, Galaxy Watch Active, Garmin VivoFit, and Jawbone UP. These devices are worn on the wrist and allow people to keep tabs on a range of lifestyle metrics, notably steps taken, heart rate, physical activity level, and calories burned per day.
According to a recent systematic review, the energy expenditure estimates of fitness trackers are generally reliable [4]. Moreover, the bias of misreported data from these devices tended to underestimate the measured BMR for study participants.
If you wear a fitness tracker or smartwatch, it certainly can't hurt to use the data it provides in conjunction with other tracking methods. Try comparing your device's estimated daily calorie expenditure with the number predicted by the Mifflin-St. Jeor equation and see how similar they are. If they're nearly identical and you are losing weight at a reasonable rate (e.g. 1-2 pounds per week), odds are those calorie estimates are accurate.
Heuristics (i.e. Trial and Error)
Intuitively, you can determine how many calories you need a day by simply tracking your calorie intake and body weight over time. For reliability, take your body weight every morning on an empty stomach after using the bathroom. At the end of the week, add up your daily weigh-ins and divide by seven to get an average. Doing so will mitigate any aberrations that arise from water weight fluctuations, food waste that's still "with you," etc.
After 2-3 weeks of counting calories and monitoring your weight, you should have a general idea whether you're eating too much, too little, or just the right amount. If you gain weight, you need fewer calories; if you lose excessive amounts of weight, your calorie deficit is likely extreme. (Rapid weight loss might seem encouraging initially, but it's not a healthy approach, nor is it sustainable.)
"How Many Pounds Can I Lose Per Week?"
There is no hard rule on how much weight you can lose per week. It ultimately depends on how many pounds you need to lose to get to a healthy weight.
Someone that's 100 pounds over their ideal weight may be able to safely lose 3-5 pounds per week during the first month or so. On the contrary, an ultra-lean bodybuilder might struggle to lose more than half a pound in a given week, no matter how aggressive they are with their calorie deficit.
Typically, the leaner you get, the slower you lose weight (especially if you're trying to retain as much muscle mass as possible). Don't beat yourself up if you lose "just" one pound per week; progress is progress.
Keep the big picture in mind, and don't worry too much about short-term weight changes. Losing weight and getting in shape take time. It's not a sprint; it's a marathon. Enjoy the journey and celebrate stepping stones along the way. Speaking of celebrating, let's briefly discuss why cheat days and cheat meals are not how you should "celebrate" short-term weight loss.
"How Often Should I Have a Cheat Day to Lose Weight?"
Contrary to popular belief, cheat meals and cheat days are rarely going to help you lose weight in the long run. People often use a weekly cheat day as a "reward" for sticking to their weight-loss diet for six consecutive days or another finite streak of time.
But here's the problem with the "restrict-reward" mentality when it comes to losing weight: You start to view certain foods as wholly "bad" or "unhealthy," and others like the opposite. Burgers, pizza, ice cream, donuts, and candy all become "off-limits" in any amount.
So, it's chicken breast, rice, and broccoli five times a day. Sticking to the same five or six "clean foods" day in and day out may actually be counterproductive by conditioning your brain to believe that everything else is inherently going to stymie weight loss.
When we look at the empirical and anecdotal evidence, it's patently clear that's not the case. Research actually shows that people who follow a "flexible diet" have better long-term weight loss results than those who follow a "rigid diet" [5].
Essentially, the type of food you eat is less of an issue than the amount of food you eat. Remember, calories in vs. calories out is the primary metric to track for losing weight. Controlling portion sizes is key if you're trying to shed pounds.
Now, that's not to say you should make it a habit to eschew wholesome, nutrient-dense foods and subsist on Twinkies and Oreos. The micronutrients, carbohydrates, fiber, essential fatty acids, and protein in food are not all created equal. You absolutely can lose weight eating nothing but greasy cheese pizza for every meal so long as you're in an energy deficit, but that's probably not going to be a wise approach if you want to maintain your hard-earned muscle since you'd be consuming very little protein.
Everything in moderation. If you want a few spoonfuls of ice cream after dinner and it won't put you over your calorie goal for the day, then live a little! There's no reason to believe you won't lose weight just because you eat food that your taste buds actually enjoy. A bland, uninspired diet of tilapia and asparagus six times a day will not help you lose weight faster than a flexible diet so long as the calorie and macronutrient content is relatively the same.
Eat Fewer Calories, Move More, and Stay Consistent
The less stressful you make the process, the better it will be for your long-term results. Losing weight is hard enough as is, don't make it more complicated than it needs to be. Eat fewer calories, move more, and stay consistent. If you do that, you will reach your goal weight in due time.
Lastly, many people wonder if taking a fat burner supplement will help them lose weight faster. Well, it depends. There are thousands of weight-loss pills on the market, and most of them are no better than a sugar pill.
Even as a dietary supplement company, we won't tell you that you need a fat burner to get in shape and lose weight. You should be skeptical of anyone that suggests otherwise. As much as we love our products, they aren't going to "do all the work for you." Taking any supplement without following a proper weight-loss diet and keeping up with exercise is just a waste of your money.
But in conjunction with a healthy lifestyle, supplementing with an evidence-based fat burner can help boost energy levels, reduce food cravings, facilitate fat breakdown, and improve mood. You can learn more about the science and research behind Transparent Labs Fat Burners by clicking below: