The Crossfit Nutrition Guide – Best Diets, Macros and Plans

When it comes to getting great results in CrossFit, optimal nutrition is key.

However, knowing what to eat (and why) isn’t always clear. CrossFit has evolved significantly since its inception, and athlete nutrition around it has also changed.

Today’s CrossFit athletes eat differently than the average person just trying to learn the movements or lose a bunch of weight.

Which begs the question, what is the best nutritional approach when doing CrossFit?

This CrossFit nutrition guide will teach you the basics of following a diet on CrossFit—the best approaches, how to count macros, and plans you can rely on for weight loss and better performance.

What Is the Crossfit Diet (AKA the Zone Diet)?

The original diet prescribed by CrossFit was the Zone Diet.

This recommendation goes back as far as CrossFit Journal Issue 21 from 2004, when coach Glassman initially suggested Zone as the optimal approach for CrossFit.

Created by Dr. Barry Sears more than 30 years ago, the Zone Diet breaks your meals down into blocks, which help balance your macronutrients and moderate caloric intake to promote weight loss and muscle recovery.

What Is a Block?

A block is a measurement to determine how many grams of carbs, protein, or fat a CrossFit athlete should eat. It’s a concept designed for the Zone Diet.

On the Zone Diet, one block is equal to:

  • 7 grams of protein
  • 9 grams of carbs
  • 1.5 grams of fat (animal sourced) OR 3g of fat (plant-sourced)

This helps form the foundation of the Zone Diet’s balanced macronutrient distribution: 40 percent carbs, 30 percent protein, 30 percent fat.

How Many Blocks Do You Need?

This depends on your size, how much lean muscle mass you have, how much you exercise, and your overall fitness and/or weight loss goals. 

The average male eats about 14 blocks per day. The average female eats about 11.

According to the Zone Diet’s website, users can figure out how many blocks they should eat by calculating their bodyweight, body fat percentage, and amount of physical activity.

There are free Zone Block calculators available online.

Block Examples

The Zone Diet recommends users pick from one of two methods to measure out their blocks:

  • The eyeball method
  • Weighing and measuring

Using the eyeball method takes practice. Learning how much of each food constitutes one block and breaking it up throughout the day takes practice.

Weighing and measuring is more precise and offers some advantages whether or not you choose the Zone Diet.

Weighing and Measuring Foods

Any CrossFit athlete, regardless of experience, can benefit from weighing and measuring food. Even if you only do it for a couple weeks.

Here are some of the benefits and drawbacks:


  • More precise weight loss
  • Eliminates many of the variables that come with eating/cooking
  • Helps you understand the portion sizes you need to eat to reach goals
  • Good practice for meal prepping and cooking in bulk
  • A good way to save money long-term
  • Allows you to practice different diets (Zone, IIFYM, etc.)


  • Time-consuming
  • Puts your eating on a schedule, which may take some getting used to
  • Meals can get repetitive if you don’t make enough
  • May require an initial investment (extra groceries, freezer bags, Tupperware containers, seasonings, etc.)

Other Popular Crossfit Diets

How to eat for optimal CrossFit performance has evolved as the sport has grown.

While Zone could be a great tool for someone new to CrossFit or someone wanting to lose weight, there are other popular diets that might help you reach your goals if you’re more advanced.

The IIFYM Diet (Counting Macros)

Counting macros, or macronutrients, is a weight loss and performance strategy where you count the amount of protein, fat, and carbs you eat each day.

IIFYM, which stands for “If It Fits Your Macros,” was one of the first popular brands to promote this style of eating.

Today, CrossFit athletes use companies like RP Nutrition to streamline their macronutrient counting to get great results.

Each macro (protein, fat, and carbs) contains a specific number of calories. Like the Zone diet, this means you can effectively guarantee weight loss or strength gains if you follow your macros consistently (and train hard).

The other benefit IIFYM users receive is they can eat anything they want, so long as it fits their macros. This doesn’t give people a license to eat junk food—but does allow for occasional splurges. 

The Paleo/Primal Diet

The Paleolithic diet and the primal diet are two whole-food source diets that are also popular in CrossFit.

Aptly named, the paleolithic diet attempts to mimic the nutritional approach of our ancient ancestors. By eating the foods we were designed to eat (meat, fruit, veggies, nuts, seeds), you can lose weight, improve health, and boost performance.

The Primal diet is very similar to paleo. It was invented by Mark Sisson of Mark’s Daily Apple (a health blog) to be a slightly less restrictive version of paleo.

For example, Primal dieters can enjoy occasional dark chocolate and a glass of wine from time to time. The diet seeks to help you build a lifestyle around your nutrition instead of being completely restrictive towards some foods.

What About Vegans?

Being plant-based or following a vegan diet is totally possible as a CrossFit athlete.

Like any of the other diets mentioned, the key to being a vegan CrossFitter is eating the right amount of food and prioritizing nutritious foods that’ll promote recovery and fuel your workouts.

Perhaps the biggest drawback to being vegan on CrossFit is the lack of complete protein sources available.

Many plant-based protein sources don’t offer all the essential amino acids your body needs for strength gains, hypertrophy, and recovery. So you may need to source multiple foods (rice and beans, for example) at one time to get what you need.

Another drawback could be price: CrossFitters tend to eat a lot, and vegan alternatives can get expensive.

However, it is doable. Athletes who wish to go this route should monitor their intake and see which essential macronutrients and vitamins they are missing, then consider supplementing with those things.

What About Intermittent Fasting?

In recent years, intermittent fasting (IF) has exploded in popularity as a weight loss method. It’s also possible to use CrossFit and intermittent fasting together, but there are some things to consider. 

The most popular IF method is the 16/8 protocol. In this rendition, users eat their meals for the day in an eight hour window then fast for sixteen hours. 

A common template is to stop eating by 8pm then eat again at noon the next day. Basically, skip breakfast and avoid late-night snacking. At least half of your fasting window is spent sleeping.

There are other forms of IF, some of which are extreme. For example, fasting for between 24 and 72 hours is not unheard of. But that method is not recommended for a high-intensity fitness program like CrossFit.

Intermittent fasting is best for CrossFitters who either:

  • Have specific weight loss goals
  • Work out in the evening
  • Don’t mind/don’t have adverse reactions to working out on an empty stomach

Be sure to start slow with IF and stay hydrated. If you’re used to eating before you work out, it’s probably a good idea to do a few ramp-up workouts on an empty stomach until you adjust.

Best Food To Eat for Crossfitters

Regardless of which diet you choose to follow, CrossFitters should base their diet around whole food sources

That means lean proteins, healthy fruits and vegetables, and other nutrient-dense foods. Examples include:

  • Protein. Chicken, pork, beef, fish, seafood, eggs.
  • Fat. Olive oil, avocado, nuts, coconut oil, full-fat yogurt, full-fat dairy
  • Carbs. Fruit, vegetables, and more healthful, non-paleo options (if you’re following a different diet) like whole grain carbohydrates, potatoes, rice, quinoa, and oats.

These foods contain the macronutrients (protein/fat/carbs), and also contain micronutrients, which are the vitamins, minerals, and other trace nutrients you need for overall health, wellness and disease prevention.

Foods To Avoid for Crossfitters

CrossFit athletes would do well to avoid most processed and sugary foods. This is the case whether you’re a beginner or advanced, and especially if you’re trying to lose weight.

  • Processed food. Chips, cereal, microwave meals, processed meat products, 
  • Sugary foods. Cakes, cookies, ice cream, soda, canned fruit, other foods made with added sugar

One of the main goals of CrossFit is to make health and fitness a lifestyle. Processed foods contain unhealthy oils that increase disease risk and sugar that decreases insulin sensitivity and promotes weight gain.

But because CrossFit and nutrition are supposed to be a lifestyle, it’s okay to indulge every once in a while. 

A general rule of thumb is to follow the 80/20 rule (eat well 80 percent of the time) or allow for one cheat meal/cheat day each week.

Sample Menu for CrossFit

Here are some sample menus of what you might eat if you followed any of the CrossFit nutrition plans we’ve discussed so far.


  • Zone: 4 large eggs (4 blocks), 1 cup of oatmeal (3 blocks) with berries (1 block), 4 tbsp of avocado
  • Paleo: 3 eggs, 1 or 2 strips of bacon with a side of veggies
  • Vegan: Oats with a tablespoon of nut butter and fruit 
  • IIFYM: Portioned-out 3 eggs, 4oz of mushrooms and spinach, 2oz of cheese, 1 slice of toast
  • Intermittent fasting: Skip breakfast or black coffee


  • Zone: 4 ounces of chicken breast (4 blocks), a salad made with kale, onions, beans, and olive oil (4 +4 blocks) 
  • Paleo: 3 eggs, 1 or 2 strips of bacon
  • Vegan: Beans or lentils with rice, a salad, and a piece of fruit.
  • IIFYM: 5 ounces of ground turkey, 
  • Intermittent fasting: Any of the meals above! 

Afternoon Snack

  • Zone: ¼ cup of cottage cheese, 2oz of carrots, 3 celery stalks, 5 olives
  • Paleo: handful of nuts
  • Vegan: A slice of vegan cheese and a handful of nuts
  • IIFYM: Protein bar
  • Intermittent fasting: A greek yogurt or something light!


  • Zone: 3 ounces of fresh fish, 1.33 cups of zucchini, 1 large salad with light dressing
  • Paleo: Fresh salmon fillet, medley of sauteed veggies
  • Vegan: Tempeh, a quinoa salad with fresh herbs and veggies
  • IIFYM: 4 ounces of steak, 1 cup of rice, a side of veggies cooked in olive oil
  • Intermittent fasting: skip breakfast

Evening Snack

  • Zone: 1 hard boiled egg, half an orange, 12 peanuts
  • Paleo: baby carrots, a bite of leftover steak from dinner
  • Vegan: Vegan baked good or bar
  • IIFYM: An apple with peanut butter
  • Intermittent fasting: skip evening snack to limit fastening hours

Calorie Intake (How Much Should I Eat?)

Caloric intake, like so much of CrossFit nutrition, is an individual thing. Based on your size, fitness experience, activity level, and goals, there’s an optimal number of calories your body needs to take in.

A good way to calculate your body’s caloric intake is to use a BMR calculator.

BMR stands for basal metabolic rate, which is the number of calories your body burns each day doing absolutely nothing. This is your baseline. (Example: 2,200 calories)

Next, figure out your daily caloric expenditure. Wear a fitness tracker or estimate it. A good guideline for a one-hour CrossFit class is between 300 and 500 calories.

Total those numbers together: 2200 + 300 = 2500 calories.

Finally, set your calorie intake based on your CrossFit goals:

  • Eat 2,500 calories each day if you want to maintain weight and performance
  • Eat approximately 2750 calories (baseline + 10 percent) to add lean muscle and size
  • Eat approximately 2250 calories (baseline – 10 percent) to lose body fat

The 10 percent guideline is good to start with. But ultimately, the mirror and scale will tell you if you need to make further adjustments. Don’t exceed 15 percent calorie restriction/addition, though, as it might be too extreme.

Diet Plan To Lose Weight

The best CrossFit diet plan to lose weight is either Zone or counting macronutrients.

Both protocols really dial in portion control while still giving you exactly how much you need to work out.

More and more, studies are determining that overeating and binge eating are two of the biggest hurdles towards weight loss success. Zone and IIFYM help you reign in the calories to help you reach your weight loss goals.

Intermittent fasting is also a good protocol for weight loss. However, IF is more of a strategy implemented inside of a nutrition plan. You can add it in if it fits your goals and doesn’t hamper performance.

Diet Plan for Muscle Gain

The best CrossFit guide for muscle gain is paleo or, once again, counting macros.

The paleo diet doesn’t call for any specific number of calories. That’s good, seeing as you need to eat at a slight caloric surplus to actually gain muscle. 

Paleo and Primal also encourage you to eat plenty of protein, which helps rebuild muscle tissue after tough workouts. 

To gain muscle as a CrossFit athlete counting macros, here are some guidelines:

  • Eat between .7 and 1g of protein per day per pound of lean body weight
  • Eat 25 to 30 percent of your daily calories from healthy carbs
  • Don’t eat at more than a 10 percent caloric surplus

Counting macros can also be effective, so long as you set your macronutrient target correctly.

What About Supplements?

CrossFit supplements are an important part of boosting performance and recovery.

Popular supplements include:

  • Whey protein. Good for post workout recovery and fueling performance if you’re doing multiple workouts in one day.
  • BCAAs. Good for boosting recovery and enhancing workout performance.
  • Pre-workout. Avoid the ones with lots of caffeine and unpronounceable ingredients. Look for a basic healthier pre workout with a boost of caffeine, ginseng, and a little beta alanine. Many people prefer to just drink coffee.
  • Beta alanine. Increases muscle capacity and reduces fatigue.
  • Creatine monohydrate. Creatine has been shown to boost endurance performance in workouts. 
  • Fish oil. Contains vital omega-3 fatty acids, which are good for reducing inflammation and promoting overall health and wellness.
  • Multivitamin. To cover your nutritional bases and make sure you’re getting all the vitamins and minerals you need.
  • Melatonin. A popular before-bed supplement that can help boost recovery by promoting deeper levels of sleep.

Keep in mind, though: supplements are meant to add to your already-dialed-in nutrition plan. You can’t out-supplement a bad diet.


There are many different CrossFit nutrition protocols that work. The key is to experiment and find one that works for your goals and personality.

Ultimately, you’ll get the best results by sticking to a diet and workout program for a long time. Consistent efforts lead to the best results.