The IIFYM diet means, “If It Fits Your Macros.” It’s based on the number of calories you need daily, but the emphasis is on your macronutrient intake, or the grams of protein, fat, and carbohydrates that you consume. 

Following the IIFYM diet can be a sensible way to lose weight, since it’s based on established principles of weight loss and it doesn’t put any foods off limits. Once you find out your daily goals for macronutrients and you’re ready to start the IIFYM diet, you can depend on Netrition to get foods that can help you stay on the plan and be satisfied.

How the IIFYM Diet Works

The IIFYM diet depends on calorie balance. Like any weight loss diet, it helps you lose weight by limiting the amount of calories you consume compared to the amount of calories you burn. You consume calories in the foods and beverages you eat. You burn calories to stay alive, do regular activities, and exercise.

To lose weight, you need to consume fewer calories than you expend, or burn. That difference is called a calorie deficit. It takes a deficit of 3,500 calories to lose about 1 pound of body fat. That means the following.

  • To lose ½ pound per week, you’d need an average daily deficit of 250 calories.
  • To lose 1 pound per week, you’d need an average daily deficit of 500 calories.
  • To lose 2 pounds per week, you’d need an average daily deficit of 1,000 calories.

You can create your deficit by increasing your exercise, decreasing the amount of food you eat, or both. 

When you’re following the IIFYM, you set a calorie level that will help you lose weight at the rate you want. Then you break your calorie limit down into proteins, fats, and carbohydrates. These are macronutrients, or macros, and they’re the main sources of calories in the diet. (Alcohol also has calories, but it shouldn’t be a significant source). 

Calculating Calories on the IIFYM

There are a few steps to getting started with the IIFYM to help you know your macro goals. Once you know them, you can figure out which foods to include, and how much of them.

First, you need to calculate your calorie needs for weight maintenance. That is, how many calories do you need to eat each day to keep your current weight stable? 

You can do this using an online calculator, or you can use an equation such as one of the following for women or men. 

  • Women: BMR = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (years) – 161
  • Men: BMR = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (years) + 5

When using these equations, be sure to note that they’re in kilograms and centimeters. There are 2.2 pounds in a kilogram, and 2.54 centimeters in an inch.

After you get this baseline value, you need to adjust this calorie level according to your activity level. You can do this using an online calculator. Some approaches include the following.

  • Multiplying by an activity factor that reflects your general activity levels.
  • Accounting for your workouts as well as physical activity that’s part of your lifestyle.
  • Estimating your overall activity.

Next, you need to change your calorie needs to reflect the fact that you want to lose weight, not maintain weight. You can do this by subtracting a number of calories, such as 250, 500, or 1,000 daily, or by multiplying your weight maintenance number of calories by a value such as 0.8 or 0.85.

Macro Goals on the IIFYM Diet

The final step to getting ready to start the IIFYM diet is figuring out your daily limit for grams of protein, fat, and carbohydrates. 

For protein, the goal is to hit 0.7 to 1 gram of protein per pound of body weight per day. So, if you weigh 200 pounds, your daily protein goal is 140 to 200 grams of protein per day. Since protein has 4 calories per gram, this works out to 560 to 800 grams of protein per day.

For fat, the goal on IIFYM is 0.25 to 0.4 grams of fat per pound of body weight per day. If you weigh 200 pounds, that works out 50 to 80 grams of fat per day. Fat has 9 calories per gram, so that turns out to be 450 to 720 calories from fat daily.

To come up with daily carb goals, start with your daily calorie limit. From that value, subtract the calories from protein and fat to get calories from carbs. Carbs have 4 calories per gram, so divide your calories from carbs by 4 to get grams of carbs per day.

And those are your macros!

Foods on the IIFYM Diet

So, what can you eat on the IIFYM diet? You’ll notice that there aren’t any guidelines besides the amount of grams of protein, fat, and carbs each day. That means you get to choose which foods to eat. 

These are some examples of protein, fat, and carb foods.


These are some high-protein foods.

  • Fish, shellfish
  • Skinless chicken, lean ground beef and turkey, lean pork and beef
  • Fat-free cheese


These are some high-fat foods.

  • Olive oil, vegetable oils
  • Butter, lard, shortening
  • Salad dressings
  • Avocados


These are some high-carb foods.

  • Candies, jams, gelatin, popsicles
  • Bread, bagels, English muffins
  • Cereal, oatmeal, rice, pasta
  • Crackers, pretzels, cake, popcorn
  • Potatoes, corn, sweet potatoes
  • Fruit

Some foods don’t fit into just one category. You’ll need to be sure to count each of their macros when you eat these types of foods. Here are some examples.

  • Proteins and fats: nuts, peanut butter. seeds, fatty meat, cheese
  • Carbs and protein: beans, fat-free yogurt, veggie burgers
  • Carbs and fats: fried potatoes, ice cream, fruit pies, muffins, chips, cookies
  • Proteins, fats, and carbs: whole milk, pizza, burritos

What If I’m Gluten-Free, Vegan, or Following Another Diet Pattern?

That’s fine! The IIFYM approach can work for you, too. It’s up to you to decide how to reach your macro goals. These are some examples.

  • Gluten-free: choose gluten-free sources of carbs, such as rice, oats, and potatoes.
  • Vegetarian: Get proteins from dairy, legumes, and other non-meat products.
  • Vegan or plant-based: get your proteins from tofu, beans, lentils and other plant-based sources instead of from animal-based sources.
  • Paleo: Carbs can come from fresh fruit, sweet potatoes, corn, beets, and winter squash, such as butternut and acorn squash.

You get to choose which foods to eat. For help, you can browse the Netrition store. We have all kinds of specialty products that can fit into specific meal patterns while tasting delicious and satisfying your cravings.

Getting More from Your IIFYM Diet

The IIFYM diet specifies how much of each macro to choose, but it doesn’t suggest which types of foods to choose or limit. It also doesn’t address micronutrients, or essential vitamins and minerals. 

You can definitely lose weight eating any type of food, as long as it fits into your macro goals, but there are some benefits to choosing healthier foods. Here are some benefits.

  • They’re often more filling. That means for the same amount of macros and calories, you can feel more full. That can help you eat less and lose more weight.
  • They can take more energy to digest. That means you burn a few extra calories and lose weight a little bit faster. 
  • They can be higher in vitamins and minerals, so you’re more likely to stay healthy as you lose weight.

Generally, more processed foods and fatty animal products are less healthy, and less processed and plant-based and leaner animal foods are healthier. These are some foods to think about.

  • Healthier: Nuts, peanuts, skinless chicken, fish, seafood, beans, lentils, whole grains
  • Less healthy: candy, sugar-sweetened products, fatty and processed meats, frozen meals, refined grains, fried foods

Making Your IIFYM Diet Easier

Are you finding that it’s hard to get enough protein to reach your goals? Are you needing to cut out favorite foods to stay within your carb goals? Is sticking to your IIFYM diet too hard because food prep is taking forever? 

Let Netrition help! Netrition has a wide variety of healthy foods designed to help you lose weight. They’re delicious and ready to eat or ready in seconds. They can fit into special diets, such as keto, paleo, vegan, or gluten-free. And, they can help you reach your macros when you choose foods such as Low-Carb Cereals and Breads, High-Protein Snacks and Entrees, and more.

Weight loss is hard, but it can be easier when you’re allowed to eat foods you love and you have flexibility in your meal plan. The IIFYM offers flexibility within a set of guidelines that let you choose foods you love. It’s based on sound principles, such as calorie counting, and it may be right for you. Ask your doctor if it seems like a good idea to try the IIFYM, and be sure to check Netrition to see which healthier versions of treats you can find to make sure you stay within your ranges for macronutrients.

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