Women’s Health 8 MIN READ

IIFYM: The Diet Taking the Fitness World by Storm

IIFYM, meaning ‘If It Fits Your Macros’, is a diet that has been getting plenty of attention recently on social media and in fitness circles, among people who are tired of failing at stringent diets.

Written by Abhay Puri

Mar 28, 2022
iifymo diet storm

IIFYM, meaning ‘If It Fits Your Macros’, is a diet that has been getting plenty of attention recently on social media and in fitness circles, among people who are tired of failing at stringent diets. First designed by fitness guru Anthony Collova, IIFYM is a new approach to dieting that works towards weight loss without placing restrictions on particular food groups. Rather than looking at calories or a single category of food, the IIFYM diet tracks macronutrients instead.
Macronutrients, also known as macros, are food molecules that the body breaks down and converts to energy. There are 4 types of macros: proteins, carbohydrates, fat and alcohol—IIFYM, however, tracks only the first three.

iifym fitnessworld storm


  • The IIFYM diet, meaning ‘If It Fits Your Macros’, has gained popularity because it hinges on ensuring that you consume the right amount of ‘macros’ (macronutrients) daily rather than emphasizing on the elimination of carbs or sugars,
  • IIFYM can help with weight loss, but if you are only concerned with meeting your macros and don’t pay heed to factors like blood sugar, regular mealtimes and cholesterol levels, it may not be beneficial for your overall health in the long run,
  • On account of the diet plan’s strong emphasis on macros, micronutrients such as vitamins and minerals may be neglected within the IIFYM framework and people following the diet may not get enough of them.

The IIFYM diet has gained popularity because it hinges on ensuring that you consume the right amount of ‘macros’ daily in order to reach your weight goals—a refreshing change from strict calorie-counting and the emphasis on the elimination of things like carbs or sugars. Instead, it is based on the idea of eating fewer calories than you burn and distributing them between your macros based on your metabolic rate and body type. Though it’s usually adopted for weight loss, IIFYM can also be tailored for use by those who want to gain weight or muscle or those who simply want to maintain their current weight.

How to follow IIFYM

The first step towards following the IIFYM diet is knowing your macros: protein and carbohydrates each contain 4 calories per gram, while fat contains 9 calories per gram. As discussed, alcohol is the fourth macronutrient and contains 7 calories per gram.

Next, you need to calculate your daily macros. Various websites offer a macro calculator that uses your weight and goals to calculate how many grams of protein, carbs and fat you need to consume on a daily basis. You can also do the following to calculate your macros manually:

  • Work out your basal metabolic rate: Basal metabolic rate, or BMR, is a measure of how much energy your body uses when it is at rest. It can be determined using a standardized equation based on your age, gender, height, weight and body-fat percentage.
  • Account for activity levels: Your daily activity level—including how much exercise you get, any training you undertake and your overall lifestyle—is then arrived at by multiplying your BMR by a factor to find your total daily energy expenditure.
  • Adjust according to weight goals: Depending on your weight goals and total daily energy expenditure, you can either reduce your daily calorie intake by 10–25 percent (to lose weight) or increase it by 5–15 percent (to gain weight).
  • Determine your macros: After determining the ideal calorie intake depending on your weight goals, remember that your protein intake should be between 0.7–1 grams per pound of body weight, your fat intake should be between 0.25–0.4 grams per pound, while the remaining calories can be allotted to carbohydrates. The idea behind allocating more calories to protein is to preserve lean muscle mass while reducing fat.

If this sounds too complicated, you can rely on the many macro calculators found online that offer a fairly accurate figure after you input your personal data. Once you have determined how many grams of protein, fat and carbs you need to consume in a day, the next step is to stay within these limits daily.

The best way to meet these macros is to track food intake, be aware of the caloric value of what you consume and adjust as required. Many apps and websites allow you to do this and offer details of the macronutrients present in various foods. Some people also purchase a digital scale in order to be able to weigh their food in grams, for the most accurate macronutrient calculations.

Foods that are high in protein, such as meats, dairy products, eggs, legumes, nuts and seafood, are more likely to help you meet your macros. Foods high in fat, such as nuts, avocados, olives, fatty fish and dairy products, are also important to include, while the rest of the diet can comprise foods high in carbs such as grains, bread, cereals, pasta, fruits and vegetables.

fitnessworld by storm

The pros and cons of IIFYM

Here are some purported benefits of the IIFYM diet.

  1. Flexibility and discipline: A major advantage of following this diet is that no foods are forbidden, and it is very flexible. This makes meal planning easier and sees a greater likeliness of people sticking to their diet. For instance, a chocolate bar and a piece of salmon may have similar fat levels, so you could consume either in order to work towards your macro goal—though the chocolate bar would also add to your carb levels, while the salmon would add to your protein levels. Because there are no limits on what you can or cannot eat, you simply have to stay within your macronutrient goals—or not exceed them by more than a couple of grams, in order to begin to see results.
  2. Increasing awareness and mindfulness of food consumption: Following IIFYM helps people have a better understanding of what they’re eating and might also lead to the consumption of more diverse foods since nothing is off the table.
  3. Can help in weight loss: Although research on its weight-loss effects is fairly limited, there is plenty of evidence suggesting that diets like IIFYM that prescribe a higher intake of protein can improve metabolism and help maintain weight loss over longer periods of time. Similarly, food tracking and calorie reduction, which are the key components of IIFYM, have also been linked to weight loss by various studies lending credence to the efficacy of this diet.
  4. Can be tailored for use for those unable to exercise: Since IIFYM takes physical activity levels into account when your macros are calculated, even individuals who are not able to exercise or have limited activity/mobility may benefit from following this diet.
  5. Can be effective in combating PCOS: Women with PCOS (poly-cystic ovarian syndrome) can find it very difficult to lose weight due to hormonal imbalance. Obesity is believed to worsen the condition. IIFYM can be tailored to help women with PCOS lose weight.

There are also some potential downsides to IIFYM.

1. Does not consider micronutrients: On account of the diet plan’s strong emphasis on macros, micronutrients such as vitamins and minerals may be neglected within the IIFYM framework as it does not account for these, and people following the diet may not get enough of them. Since billions of people suffer from vitamin or mineral deficiencies already, this is something to remember when following the diet.

2.Does not account for other health conditions: Another problem with IIFYM is that it may not be appropriate for people who are ill, recovering from injury or suffering from other health or hormonal conditions. For instance, people with diabetes would have additional restrictions in terms of their carb or sugar intake, while those with certain kidney problems would need to watch their protein consumption.

3.Requires more research beyond social media: The fact that there has not been much peer-reviewed research in terms of following IIFYM, as it’s a relatively new phenomenon, can also be a concern. Moreover, many proponents creating templates for macros are social media experts who may not actually possess any qualifications in nutrition. Keeping this in mind, it’s essential to remember that a holistic approach to eating and weight loss is still required.

4.Might exacerbate disordered eating: Research has found a strong association between food or calorie tracking and the development of eating disorders, particularly in college students and young women. So IIFYM, which is based on tracking macros, may not be recommended for individuals with a history of eating disorders like anorexia or bulimia. It’s important for healthcare professionals to screen their patients before recommending it in such cases.

Factors like physical activity, sufficient sleep and stress management are still extremely important. If you are only concerned with meeting your macros but don’t pay heed to factors like blood sugar, regular mealtimes, cholesterol levels, and so on, it may not be beneficial for your overall health in the long run.


IIFYM follows the same calorie-balancing principles that many successful diets do while offering more flexibility and freedom, as it is easier to follow and less restrictive than many others. It also helps you to be mindful of what you eat and track your food consumption more carefully.

For these reasons, if you are looking for a new diet plan, IIFYM could be a good long-term option. As long as you are aware of its drawbacks, careful about consuming enough micronutrients and making generally healthy choices when it comes to food, sleep and exercise in addition to meeting your macros, IIFYM claims to be beneficial in terms of your weight goals. Consult your nutritionist or healthcare provider before adopting a new diet regime.

Disclaimer: The contents of this article are for general information and educational purposes only. It neither provides any medical advice nor intends to substitute professional medical opinion on the treatment, diagnosis, prevention or alleviation of any disease, disorder or disability. Always consult with your doctor or qualified healthcare professional about your health condition and/or concerns and before undertaking a new healthcare regimen including making any dietary or lifestyle changes.


  1. https://www.healthline.com/nutrition/iifym-guide#calculating-your-macros
  2. https://www.self.com/story/whether-the-if-it-fits-your-macros-diet-aka-iifym-can-really-help-you-lose-weight
  3. https://pubmed.ncbi.nlm.nih.gov/24675714/
  4. https://pubmed.ncbi.nlm.nih.gov/26554314/
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2905334/

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