If you want to learn how to use flexible dieting, also known as IIFYM, to lose fat, gain muscle, and stay healthy while eating the delicious vegan foods you enjoy, then you want to read this article.

What Is IIFYM?

IIFYM is short for “If It Fits Your Macros.”

Macros, short for "macronutrients," is the term used to describe the 3 main macronutrients: protein, carbohydrates, and fat.

Rather than placing all of your attention on counting calories or demonizing certain macronutrients, IIFYM focuses on meeting daily macro goals. Done correctly, this provides a consistent calorie intake, but one that can be personalized in many different ways.

In other words, IIFYM is a diet trend that allows you to eat anything you want whenever you want it and still reach your weight goals! The catch? You have to eat the right amount of carbohydrates, protein, and fat.

Does IIFYM Actually Work?

Is IIFYM effective for both losing fat and gaining muscle? Is it true that you can eat the foods you love while improving your physique?

In short, the answer to these questions is yes.

The principles of IIFYM, when properly applied, allow you to get the body you want by eating the foods you really love.

IIFYM is NOT a diet that consists of only eating junk food. It is a counting system used for accuracy so you can fit junk foods into your diet in moderation while consuming the bulk of your macros from healthy whole foods.

When done right, IIFYM is a solid balance of moderation and flexibility.

Try our FREE Vegan Nutrition Calculator to figure out your macros in less than 5 minutes! Find out what you need to eat to meet your goals..

The 4 Principles of Vegan IIFYM Dieting

1. The number of calories you eat is more important than the source of those calories

2. Macronutrients matter just as much as the number of calories

3. You should get at least 80% of your calories from minimally processed, nutritious food

4. There is no need for “meal timing” so you can eat whenever it fits your schedule and preferences

Principle 1: The number of calories you eat is more important than the source of those calories

Many diet “gurus” – even in the vegan community – claim that a “calorie isn’t a calorie” and that dieting is all about what you eat, not how much.

Well, this is complete garbage.

You gain weight by eating more calories than you burn and you lose weight by eating less calories than you burn. The relationship between how many calories you are consuming versus how many you are burning is called your energy balance.

It’s that simple.

You can’t eat 50 bananas a day and expect to lose weight and get the body of your dreams. You can be the “cleanest” eater in the world, eating the most nutritious foods, and still be weak and skinny fat if you eat too much and don't work out.

I must admit I really like the idea of being able to eat as much fruit as I want and still be able to lose weight, because I freaking LOVE fruit, but the reality is not so simple.

Dieting is all about how much you eat, not what you eat.

To prove that pure calorie counting is what matters most, not the nutritional value of the food, a professor of human nutrition at Kansas State University, Mark Haub, lost 27 pounds eating Twinkies, Little Debbie snacks, Doritos, and Oreos.

Extreme? Most certainly. Unhealthy? Of course. But he proved his point.

When you feed your body fewer calories than it is burning, it must get those extra calories from somewhere, so it turns to its fat stores. When you keep your body in a calorie deficit over time, your body fat will decrease.

Principle 2: Macronutrients matter just as much as the number of calories

A calorie is not a calorie when we are talking about body composition. Whether your main goal is to gain muscle or lose fat, you need to do more than just maintain a caloric surplus or caloric deficit.

• You must eat enough protein every day to gain muscle while bulking and preserve muscle while cutting.

• You must eat enough carbs to give you the energy to push through gruesome workouts and progress in all your lifts.

• You must eat enough fat to maintain proper hormone production.

You should consume most of your dietary fat from monounsaturated fats like avocados, seeds, and nuts. Furthermore, you must pay close attention to your EPA/DHA intake, especially as a vegan. Your body can convert ALA to EPA and DHA, but the conversion ratios are very low. Consequently, I use an EPA/DHA supplement and I recommend all vegans do the same.

So protein, carbs, and fat all play an important role in your health and body composition goals. This is why counting macros is superior to just counting calories. Personally, I follow and recommend a high protein, high carb, low-fat diet for both bulking and shredding.

If you want to calculate your macros to reach your fitness goals, try our FREE Vegan Nutrition Calculator!

Principle 3: You should get at least 80% of your calories from minimally processed, nutritious food

Macros are all that matter for fitness results, but micronutrients are arguably more important for overall health. So the only problem I have with the IIFYM group is that many people tend to use it as an excuse to eat crap. And this is a serious problem because - as Professor Mark Haub demonstrated with his Twinkie diet - you can actually eat crap while improving your physique.

The reality is that your body turns carbs from Oreos into glucose and glycogen just like the carbs from kale.

But, using the principles of IIFYM as an excuse to eat junk food while getting in shape is completely stupid.

Just because you can eat a half gallon of Non-Dairy Ben & Jerry’s Peanut Butter Cookie ice cream every day and still get shredded doesn’t mean you should.

I use the principles of IIFYM to achieve my physique goals, but I don’t use it as an excuse to eat junk food all the time. I stick to a diet of mostly whole plant foods whether I am bulking or cutting and I recommend you do the same.

As a general guideline, you should get at least 80% of your calories from nutritious whole foods - preferably more. Here’s a brief list of the healthy foods you should be eating:

Protein sources:

• Lentils

• Beans (black, pinto, kidney, etc.)

• Sweet peas

• Chickpeas

• Hemp hearts (seed)

• Buckwheat

• Quinoa

• Pumpkin seed

• Spirulina

• Organic tofu

• Tempeh

Fat:

• Almonds (or almond butter)

• Walnuts

• Cashews (or cashew butter)

• Brazil nuts

• Macadamia nuts

• Hazelnuts

• Chestnuts

• Pecans

• Pistachios

• Sesame seeds

• Pine nuts

• Pumpkin seeds

• Avocado

• Flax seed

• Coconut

Fibrous Carbohydrates:

• Kale

• Cabbage

• Broccoli

• Asparagus

• Artichoke

• Bok Choy

• Eggplant

• Sweet bell peppers

• Zucchini

• Brussel Sprouts

• Cauliflower

• Mushrooms

• Parsley

• Onions

• Tomato

• Spinach

• Cucumber

• Collard greens

• Lettuce

• Leeks

• Celery

Starchy Carbohydrates

• Sweet potatoes

• Quinoa

• Couscous

• Rice

• Pasta

• Oats

• Carrots

• Legumes

Principle 4: There is no need for “meal timing” so you can eat whenever it fits your schedule and preferences

You don’t have to stick with “feeding windows,” eat protein every 2-3 hours to avoid “going catabolic,” or avoid carbs after 6PM.

And your metabolism won’t slow down if you eat 2 meals instead of 6.

I happen to prefer to eat more, smaller meals every day, but it doesn’t have any effect on my metabolism. If you prefer calorie dense foods, you can easily work them into your macros by eating fewer, higher calorie meals.

Hitting your macros is all that matters. Meal timing does not matter.

That being said, I should note that there is a slight exception to this rule. A high-protein post-workout meal or shake is a good idea if you are trying to build muscle and strength.

I also recommend that you consume some pre-workout carbs to give you the energy to crush your workouts, which in turn helps you progress in all your lifts to gain muscle and strength.

Do you have any questions about IIFYM? Send us a DM on Instagram or Facebook!