While you may have heard the old advice that “a calorie is a calorie” and “calories in, calories out are all that matter for weight loss,” more recent evidence suggests that macronutrients play an equally important role in weight loss[*].
For example, newer findings suggest that increasing your protein intake and limiting or lowering your carbohydrate intake could immediately lead to greater weight loss[*].
The science is clear that the macronutrients you eat can significantly affect your weight loss and body composition results by speeding your metabolism, helping you fill up faster, and balancing your hormones[*][*][*].
On the other hand, eating the wrong macro ratios can be detrimental to your results, leading to excess hunger, weight gain, and other health problems[*].
This article thoroughly examines different weight loss macronutrient ratios, not just the ketogenic diet. You’ll learn the easiest ways to calculate weight loss macros, the science of macros for weight loss, calories versus macros for losing weight, how keto compares to other low-carb and weight loss diets, when and how to strictly track macros, and more.
If you want to calculate effective weight loss macros without counting calories, you can do it based on your current body weight and meal frequency instead.
Here’s the simplest method to calculate daily macros with as little math as possible:
- For protein, eat at least 0.75-1 gram per pound of body weight per day, which equals approximately 30% of daily calories from protein[*].
- For carbohydrates, eat between zero and 50 grams of carbs for a keto diet, less than 100 grams of carbohydrates per day if you’d like to eat a low-carb diet, or up to 1 gram of carbs per pound of body weight per day for a moderate-carb diet.
- Instead of counting calories from fat, eat healthy fat foods at each meal along with your protein and carbs until you feel full, but don’t overeat (stop eating when you feel full).
Then, to determine what to eat at each meal, divide your protein and carb numbers by the total number of meals you typically eat per day.
For example, a 150 pound woman on a low-carb diet who eats 3 meals per day would consume 37-50 grams of protein per meal, up to 33 grams of carbs per meal, and enough healthy fats to satisfy her hunger at each meal but no more.
As another example, if a 150 pound woman was eating a moderate-carbohydrate diet and two meals each day, she would eat around 60-75 grams of protein per meal, up to 75 grams of carbs per meal, and some additional healthy fat foods to feel full.
Even though this method of determining macros is extremely simple, plenty of people can get great weight loss results from it. The easiest way to see for yourself is to give it a try for a couple of weeks, then try the other methods recommended below if you aren’t happy with your results.
How to Calculate Weight Loss Macros Based on Current Calories
If you’d like to know exactly how many grams of each macro and how many total calories to eat per day, one easy way to do it is by using your current calorie intake as a starting point.
This method works best if you’re already losing weight, or if you’re at least maintaining weight. If you’re gaining unwanted weight currently, this isn’t the right method for you (but keep reading, because the other suggestions in this article will still work well for you).
Your first step is to measure your calorie intake for a few days while eating normally to determine your baseline. Don’t worry about counting macros yet, simply log your total calories by hand or using one of the many tracking apps available. Write down the caloric content of everything you eat, then total it up for the day. Repeat for 2-4 days total.
Now average the numbers together by adding everything up and dividing it by the number of days.
For example, if you ate 1800 calories Monday, 2100 calories Tuesday, 1900 calories Wednesday, and 2200 calories Thursday, your four-day average is 2000 calories (kcal).
If you’ve already been losing weight, don’t change the daily average number. But if you haven’t been losing weight, decrease it by 10%. One easy way to do that is to multiply by 0.9, so using the above example, 2000 calories would become 1800 daily calories as a target.
Either way, the next step is to determine your daily protein, carbs, and fat intake in grams using your daily calories:
- To determine daily protein intake in grams, multiply daily calories by 0.25 (for 25%), 0.3 (for 30%), or 0.35 (for 35%), then divide by 4 (because protein has 4 calories per gram).
- To determine daily carbohydrate intake in grams, choose between 0-20 grams (keto diet), less than 100 grams (low-carb diet), or 30% or less of calories (moderate-carb diet). If necessary, you can calculate 30% by multiplying daily calories by 0.3, then dividing by 4 (because like protein, carbs have 4 calories per gram).
- The remainder of your daily calories will come from healthy fats. To calculate how many grams of healthy fats to eat per day, add together total grams of protein and carbs, multiply by 4, subtract that number from your daily calorie intake, and then divide the remaining number by 9 (since fats have 9 calories per gram).
Any of the numbers above will work for weight loss, and if you aren’t sure yet, don’t worry. The rest of this article contains more suggestions that can help you decide.
Here’s an example of the math: if your daily calorie target is 1800 calories and you’re eating 30% of calories from protein, you’ll eat 135 grams of protein per day.
Keeping with that same example, if you’re eating a moderate-carb diet, you’ll also eat no more than 135 grams of carbs each day.
To calculate your fat intake, you’d add grams of protein and carbs together, multiply by 4, subtract from total daily calories, and then divide by 9 for a total of 80 grams of fat each day.
Finally, remember to divide your target daily macros by the number of meals, then count macros each time you eat a meal by looking at labels or using an app.
While the math may seem a bit complicated, it’s not so difficult, and you only need to do the calculations once — then you can focus on hitting your daily targets, which is easier. However, be sure to double-check your work so you don’t end up with an incorrect macro calculation.
How to Calculate Macronutrients for Weight Loss Based on Target Calories
Calculating a specific number of calories usually isn’t necessary for weight loss.
That said, some people still prefer to set a calorie target and count calories along with macros, and it can be an effective approach for weight loss if that’s what you feel works best for you.
You may be familiar with the total daily energy expenditure (TDEE) formula, which is determined by calculating your basal metabolic rate (BMR) and multiplying by your daily physical activity level. However, TDEE calculations are not only overly complicated, but also tend to overestimate calorie needs in overweight adults[*].
Instead of using math-heavy metabolic equations, most people find it easier and equally effective to multiply their body weight to determine daily calorie needs for weight loss:
- Multiply your current body weight (in pounds) times 10 for a weight loss deficit if you have an average metabolism and are moderately active, or
- Multiply your current weight (in pounds) times 12 for a weight loss deficit if you have a fast metabolism, are an athlete, or are very physically active (but if you aren’t, this will be too many calories for weight loss with an average metabolism).
As an example, a 180 pound individual would consume 1800 daily calories (kcal) for weight loss unless they had a fast metabolism or were very active, in which case they’d consume around 2160 calories (kcal) per day.
Once you’ve determined your daily calorie target, to calculate your macronutrients you can simply plug the calorie number into the simple macro formulas from the section preceding this one.
Here’s what current studies say about the impact of protein, carb, and fat intake on weight loss results.
Protein Intake and Weight Loss
For most people, increasing protein intake to around 25-35% of daily calories has a beneficial effect on weight loss because a high-protein diet requires more energy to digest, helps fill you up, and also increases hormones that promote feelings of fullness and a reduced appetite[*].
A 2007 study found that for women eating a 750 calorie (kcal) daily deficit, eating 30% of daily calories from protein increased fat-burning and energy expenditure as well as reducing hunger, desire to eat, and hunger hormone levels when compared to eating 18% of daily calories from protein[*].
And a 2017 study found that overweight and obese women lost more weight and experienced better health outcomes when eating 35% of daily calories from protein compared to 27% or 20%[*].
Carb and Fat Intake and Weight Loss
Carbohydrates have 4 calories (kcal) per gram and are the easiest fuel for your body to use for energy[*].
While the rapid absorption and metabolism of carbs can be beneficial for athletes and active people, they’re also associated with a greater risk of weight gain when carbs are overconsumed, and may be a factor that leads to poor metabolic health and the risk of type 2 diabetes[*].
With 9 calories (kcal) per gram, dietary fat is more energy-dense than protein or carbohydrates, but diets that replace carb intake with a calorically equivalent amount of healthy fats show beneficial results for weight loss.
Calories vs. Macros for Weight Loss
Ultimately, calories and macros both matter for weight loss.
To lose any significant amount of weight, it’s true that your body must be in an overall caloric deficit (consuming fewer calories than you burn) for an extended period of time, and that means reducing calories below maintenance intake one way or another.
But there are a few ways you can achieve a calorie deficit, and not all of them involve counting calories:
- Eating a diet that leads to sustainable fat loss without the need for calorie counting (such as the keto diet as shown in several studies)[*][*].
- Limiting calories by practicing portion control or eating more filling healthy whole foods instead of junk food.
- Counting calories to achieve a target daily intake and remain in a deficit, which for most people is only appropriate as a short-term approach (if at all).
Some research suggests strictly counting and attempting to limit calories through willpower doesn’t work very well as a long-term weight loss or weight maintenance strategy, and that practicing healthy habits — including eating the right macros for your body and goals — may be a more effective method[*].
And for the most part, people get better weight loss and health results with low-carb diets compared to low-fat diets.
That said, not all low-carb diets are the same. The standard low-carb diet (where users typically eat less than 100 grams per day) is not the same as Atkins, which in turn is different from the ketogenic diet.
The keto diet is the lowest-carb diet of all, and most keto followers eat no more than 20-50 grams of carbs per day to achieve a state of ketosis. Along with ramping up ketone production, the keto diet also offers unique health benefits and supports feelings of fullness more effectively than other diets[*].
Use the Perfect Keto macro calculator below to easily and effectively calculate your standard keto macros:
In contrast to the standard ketogenic diet, the cyclical keto diet (CKD) and targeted keto diet (TKD) include strategic carb-ups to help boost recovery and fuel performance for active people and athletes. But generally, they’re only suitable if you’re looking to maintain weight or are very physically active.
Keep in mind that you don’t have to go keto to lose weight, but restricting carbs is easier and more effective for the majority of people than other strategies to shed body fat. And if you’ve had trouble losing weight in the past, keto might help you succeed where other diets have failed to deliver results.
We’ve also got educational articles on how keto compares to low-carb, Atkins, and Weight Watchers as well as a summary of benefits unique to keto if you’d like to learn more about how various popular diets stack up in terms of results and macro requirements.
Most people can benefit from being aware of their macronutrient intake during a weight loss diet, but that doesn’t necessarily mean you need to strictly track macros all the time.
Here’s when it makes sense to track macros using a smartphone app or old-school pen and paper:
- When you first start a new diet, tracking macros for up to a week can help you learn how to stay on track.
- If you’re not getting the results you’d hoped for, tracking macros for a few days can help you troubleshoot any issues that may be preventing weight loss.
- If you genuinely enjoy quantifying macros for the sake of accountability or insight, there’s nothing wrong with it.
Lastly, if you’re following the keto diet, testing your ketone levels to ensure you’re in ketosis can be an easier and more effective alternative to strictly counting carbs and monitoring macros once you get the hang of limiting carbs.
When it comes to weight loss, choosing the right macronutrients for your goals matters as much as your caloric intake.
While it’s true that anyone can lose weight by reducing calories to achieve a deficit, calorie-counting is more of a short-term approach that usually isn’t sustainable in the long run.
In contrast, people can often lose weight without counting calories by increasing protein, decreasing carb intake, or going keto.