How to Calculate Intermittent Fasting Macros
Need to Know:
Tracking macros while intermittent fasting can make weight loss more effective, help boost daily energy levels, and ensure that you get adequate nutrition for optimal health.
The best intermittent fasting macros for you should be personalized based on several factors, including your goals, your activity level, your gender, and your age.
You can use a macros calculator to determine the best macros while intermittent fasting.
Tracking intermittent fasting macros can help your meal plan deliver body composition or weight loss results faster and more effectively. If you consume balanced macros during your eating window, you are likely to find that you feel fuller and more comfortable during your fasting window, making the whole program sustainiable and easier to maintain .
Why Track Macros While Intermittent Fasting?
Many people use intermittent fasting, also called time-restricted feeding, for weight loss or reducing body fat. The program is easy to follow because, in order to be successful, you simply choose an eating schedule and only consume food during the hours that fall within that window of time.(5) The program doesn’t require you to eliminate any particular foods or food groups, consume any expensive supplements, or count calories. But by reducing the hours during the day when you eat, most people reduce overall calories and experience sustainable weight loss and improved body composition.
So why complicate intermittent fasting with macro tracking? The benefits are significant.
Helps maintain muscle mass for a stronger metabolism. Consuming adequate protein throughout the day ensures that you maintain muscle mass, especially during weight loss.(1) Having more muscle allows you to burn more calories throughout the day, even when your body is at rest.(2) You are also more likely to remain active during the day when you have a strong, fit body.
Reduces hunger. Making sure that you consume adequate carbohydrates, especially fiber-rich carbs, will help you to feel full longer after eating. That feeling of fullness, or satiety, is likely to help keep you feeling satisfied during your fasting hours.
Improves energy levels. Carbohydrates are your body’s preferred source of energy. Your brain especially needs carbs to function at its best and avoid the feeling of fogginess that often accompanies fasting. (3) Making sure that your carb intake falls within recommended guidelines will help you to avoid energy slumps and brain fog during intermittent fasting.
Boosts overall nutrition. One of the most significant concerns with intermittent fasting is nutrient deficiency. Studies have shown that the intake of certain key micronutrients, including calcium, magnesium, potassium, folate, vitamin C, and various B vitamins, may be affected during time-restricted feeding.(4) By tracking macros and ensuring that you get a balance of protein, fat, and carbohydrates, you increase the likelihood of consuming a wide range of vitamins and minerals.
And the best news is that tracking intermittent fasting macros doesn’t need to be complicated or time-consuming. There are various macro tracking methods that are quick and easy and involve no tedious measuring or counting.
How to Track Intermittent Fasting Macros
There are just a few steps involved in tracking macros during intermittent fasting. Follow these steps to make the most of your program.
1. Choose Your Intermittent Fasting Schedule
There are different options when it comes to intermittent fasting schedules. Including:
16:8 fasting involves fasting for 16 hours and then eating during an eight-hour window of your choosing. This is the most common plan for intermittent fasting and the easiest plan to follow for newbies.
20:4 fasting is similar to 16:8, but you generally only consume one meal per day during a four-hour eating window of your choosing. This is also a relatively easy plan to follow for beginners.
5:2 fasting involves two low-calorie days per week. You eat normally for five days, and on two non-consecutive days, you eat only 500 to 600 calories per day.
12:12 or overnight fasting involves fasting during the nighttime hours and eating during daytime hours. This plan helps eliminate mindless snacking that often occurs in the evening, but unless those calories contribute significantly to your normal food intake, this plan is less likely to be successful than many of the other plans.
Alternate-day fasting involves fasting every other day. On the fasting days, you consume food but in smaller amounts so that your total calorie intake is only about 500 calories.
There are also less common schedules, including the One Meal a Day (OMAD) plan or the Eat-Stop-Eat method, which involves choosing two days per week where you eat nothing. The days should not be back-to-back to ensure adequate calories or nutrition.
When choosing the best schedule for you, consider your lifestyle and daily schedule. For instance, if you work a job that involves a lot of physical activity, you don’t want to choose a schedule that involves no eating or severe calorie restriction for an entire day. Or if you exercise every day, you may want to choose a schedule that allows you to eat a few hours before your workout so you have adequate energy to exercise effectively.
2. Use a Macros Calculator to Determine Your Optimal Macros
There’s no need to do any complicated math to figure out your macro targets for protein, fat, and carbohydrates. Simply use a macros calculator to get your numbers instantly. Choose balanced nutrition to make sure that you get adequate nutrients during your eating window.
Selecting a more restrictive program, like a keto diet, a paleo diet, or a carnivore diet, will only make intermittent fasting more difficult and less sustainable.
3. Select the Best Tracking Method for You
Many people choose intermittent fasting as their weight loss method because it is so simple. Counting calories can be tedious, and eliminating certain food groups (like the carnivore diet or the keto diet) is too restrictive for many people. It may seem like tracking macros just makes intermittent fasting too complicated. But there are ways to track macros that don’t involve measuring food, tracking every gram of nutrients, or using tracking apps.
For example, you might choose to track a single nutrient, such as protein. If your target is 150 grams (or 600 calories per day from protein) you can figure out what foods and in what amounts will help you get there. Four ounces of chicken breast, two scoops of protein powder, and two cups of cottage cheese will help you reach that target, so you can simply set a goal to consume those foods as part of your food intake during your eating window. Tailor your target foods to your personal preferences.
You can also use the plate method instead of counting every macronutrient gram. At meal time, simply fill one quarter of your plate with a lean protein, half of your plate with fruits or veggies, and one quarter of your plate with grains. There’s no need to “add” fat to your plate, as you are likely to use oils for cooking or in sauces or dressings.
4. Plan Meals in Advance
One of the pitfalls of intermittent fasting is engaging in binge-eating when your eating window opens up. If you are ravenously hungry after making it through your fasting window, it may be tempting to open up your cupboards or refrigerator and inhale whatever is in front of you. But a smarter approach is to plan meals in advance so you have a healthy meal ready to go when it is time to eat.
You can simply schedule your meals in advance so you know what you will consume when it’s time, or you can actually prep meals in advance so the food is ready to grab when your eating window arrives. Either way, knowing what to eat ahead of time will help you to eat a more nutritious diet and gain all the benefits that come with it.
5. Make Adjustments for Sustainability
Be mindful of how you feel throughout the day. Watch for fatigue, energy dips, brain fog, or obsessive thinking about food. All of these are indicators that your schedule and your meal plan are too restrictive. While you might be able to white-knuckle through these episodes on some days, your plan is not likely to be sustainable in the long run.
To maintain energy and focus throughout the day and for the duration of your program, adjust your eating or fasting windows or adjust your macronutrient balance. Again, a balanced approach is smart to ensure adequate energy and nutrition. A balanced diet means that you consume:
10% to 35% of your calories from protein
45% to 65% of your calories from carbohydrates
20% to 35% of your calories from fat
These ranges allow you to make adjustments to each macro to satisfy your nutritional needs each day.
Tips for Success
Stay hydrated. Your hydration levels can impact your energy levels as much as your food intake. Chronic dehydration often leads to fatigue. It can also cause you to want to eat as sometimes your body confuses hunger and thirst. Make sure you are drinking enough water to keep your urine clear or light yellow.
Prioritize whole foods. You’ll get more bang for your buck when you consume foods that are closest in form to their natural state. For example, an apple is healthier than a cup of apple juice because the whole apple contains fiber. A chicken breast is healthier than a chicken nugget because nuggets often contain excess sodium and other ingredients that you don’t want or need.
Embrace variety. Eating a variety of foods will help you to keep your palate satisfied and your food cravings at bay. Grab produce in a wide range of colors when shopping for fruits and veggies. When planning your protein intake, try to consume fish at least once per week and choose plant-based protein one or two days per week.
Stay Active. When you first start tracking your intermittent fasting macros, you may want to devote your energy to proper food intake. But eventually, do your best to schedule activity during the day. You can schedule longer workouts to stay healthy or take mini-movement breaks throughout the day to meet the recommended goal of 150 minutes of moderate activity per week.(6) Also, be sure to do some strength training during the week (at least 2-3 sessions) to maintain and build muscle. (7)
Get Expert Help. If you’ve tried different intermittent fasting windows and different macronutrient ratios without success, reach out to a registered dietitian (RD) or a registered dietitian nutritionist (RDN) for help. These professionals specialize in tailoring meal plans to meet your needs and preferences. Just a single session can do wonders to help you reach your short and long-term goals for intermittent fasting.
Sources:
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Medline Plus. Muscle cells vs. fat cells
Jéquier E. Carbohydrates as a source of energy. Am J Clin Nutr. 1994 Mar;59(3 Suppl):682S-685S. doi:10.1093/ajcn/59.3.682S
Wallerer S, Schwingshackl L. Impact of intermittent fasting on micronutrient intake. Curr Opin Clin Nutr Metab Care. 2025 Jul 14. doi:10.1097/MCO.0000000000001148
Collier R. Intermittent fasting: the science of going without. CMAJ. 2013 Jun 11;185(9):E363-4. doi:10.1503/cmaj.109-4451
Yang YJ. An Overview of Current Physical Activity Recommendations in Primary Care. Korean J Fam Med. 2019 May;40(3):135-142. doi:10.4082/kjfm.19.0038
American Heart Association. American Heart Association Recommendations for Physical Activity in Adults and Kids