What is flexible dieting?

Flexible dieting involves setting calorie and macronutrients (protein, fat, and carbohydrates) goals and tracking food intake to stay within the daily budget.

Athletes and gym enthusiasts often use this method to optimize their performance, lose weight, or build muscle. 

The “flexibility” component of flexible dieting comes from the fact that no food is off-limits. As long as you eat the suggested grams of protein, fats, and carbohydrates daily, anything goes. 

How Does Flexible Dieting Work?

Flexible dieting works especially well for those with a performance or body composition goal. By having a goal (running, lifting, weight loss, gaining muscle), you can tailor your calories and macronutrients to support that goal.

Once you have a goal in mind and know what your calorie and macronutrient targets are, you can begin to track your using a food journaling application like Cronometer. Pay special attention to the total grams of protein, fat, and carbohydrate you consume. 

By tracking your macronutrient intake and aligning it with your goal, you can better manage your nutrition and support your objectives.

How to Start Flexible Dieting

If you want to begin practicing flexible dieting, it’s important first to determine your goals and the number of calories necessary to achieve them. You’ll also need to calculate the amount of protein, fat, and carbohydrates your body requires. 

From there, you should begin tracking the foods you consume and aim to get as close to your daily calorie and macronutrient targets as possible.

Let’s walk through each of the steps together.

Goals

To start practicing flexible dieting, it’s important to have a clear goal in mind. There are two options to consider: weight loss or performance-based goals (that don’t involve weight loss). 

If weight loss is your goal, you’ll need to be in a calorie deficit (eating fewer calories than you burn each day). This means that the total number of recommended calories will decrease. Learn more about how to set weight loss goals.

If your goal is performance-based, such as improving strength or endurance, you’ll need more calories to fuel your workouts. Not getting enough energy could negatively impact your performance.

Calories 

An individual’s total number of calories depends on several factors: height, weight, age, activity level, and goals. You can use an online calculator like the Body Weight Planner to identify the total calories you need daily. 

These calorie needs can be broken down into two categories: resting energy expenditure and non-resting energy expenditure.

Resting energy expenditure: The number of calories you need to maintain basic functions like breathing, heart beating, digestion, etc.

Non-resting energy expenditure: The number of calories you need to support activities like working, running, cleaning, shopping, etc.

Depending on your goals, you may need more information on the number of calories you need. Check out macros for cutting if you are trying to lose weight, and read how many calories to build muscle if you want to gain weight.

Protein

Protein is one of the essential macronutrients that our body requires in large quantities every day. Protein provides us with 4 calories per gram. 

Composed of amino acids, protein serves as the foundational blocks that our body needs to maintain our immune system, muscle function, and other crucial functions.

How much protein? 

There is no general answer here, which varies depending on the individual. The dietary guidelines for Americans for protein intake is 10-35% of your daily calories. 

One lens you can look at protein intake is your activity level. If you are engaging in resistance training, consider eating at the high end of the recommended intake. 

Additionally, you can multiply your weight in kilograms by a multiple of 0.8-2.2 g/kg.

I suggest my clients create a range of low to higher protein intake that best fits their needs. That way, they are not faced with the daunting task of perfectly hitting a precise number. 

Limitations: There are health conditions where eating a high-protein diet may not be advisable; please speak to your healthcare provider before making any dietary changes. 

Fats 

Dietary fats like those from olive oil, nuts, and salmon are another essential macronutrient. Fats provide 9 calories per gram, making them the most calorie-dense macronutrient. 

Dietary fats play a significant role in our hormone production, hunger regulation, and the growth of new cells. 

How much fat? 

Again, there is no general answer, and it will vary depending on the individual. The current dietary guidelines for Americans is 20-35% of total daily calories. 

For example: 20% of 2000 calories equals 400 calories. There are 9 calories per gram so that is 44 grams of fat. 35% of 2000 calories equals 700 calories or about 77 grams of fat per day. 

Like protein, I like my clients to use a range for each macronutrient, including fats. Based on the example above, a range of 44 – 77 grams of dietary fat per day.  

Carbohydrates

Carbohydrates come in many forms, including fruits, potatoes, rice, pasta bread, and are the third macronutrient. Carbohydrates provide us with 4 calories per gram. 

There is a wide range of carbohydrates, but those high in fiber and other vitamins and minerals provide more nutritional value. 

How many carbohydrates?

As you may have guessed, no general answer will vary depending on the individual. The current dietary guidelines for Americans is 45-65% of total daily calories. 

For example: 45% of 2000 calories equals 900 calories. There are 4 calories per gram, which is 225 grams of carbohydrate. 65% of 2000 calories equals 1300 calories or about 325 grams of daily carbohydrate. 

I have put together a few resources to help you find your macros. Read macros for a lean bulk or macros for building muscle.

Macronutrient tracking

Once you have set your mind on a goal and calculated your calories and macronutrients, all that is left is to start tracking your food intake. 

Personally, I use Cronometer, a food-tracking application that I find to be the most comprehensive. You can signup to Cronometer and 10% off a gold subscription today. There are many others, like Myfitnesspal and Lose It, to name a few. 

The main goal for tracking your macros is to accurately record your food intake and be consistent. Doing this lets you see patterns in your eating behaviors that either help or hinder your success. If you are ready to start flexible dieting, read more about counting macros for beginners.

Benefits of Flexible Dieting

There are several benefits to flexible dieting. These benefits include flexibility, self-monitoring, and improved nutrient intake. (1)

No “bad” food

The idea behind flexible dieting is that as long you have the macro budget, you can fit foods that may not be considered “weight loss foods” you can eat it. This is where the if it fits your macros IIFYM saying came into existence.

Easy to monitor calories

Everyone is familiar with the idea that you must eat less to lose weight. In the case of flexible dieting, you are able to easily account for your macronutrients in addition to your calories. 

Meeting some of your nutrient requirements

Monitoring daily intake through calorie counting has long been considered the go-to method. However, it’s important to note that calories only provide one aspect of the bigger picture of nutrition. 

By tracking your macronutrient intake, you can ensure that you’re meeting your calorie goals and your macronutrient targets. Learn more about what to expect and how long to see results from tracking macros.

Drawbacks of flexible dieting

While flexible dieting seems to be gaining popularity, it is important to highlight some potential drawbacks. 

Little to no focus on micronutrients 

Although calories and macronutrients are crucial for weight loss and performance, flexible dieting often overlooks the importance of monitoring your vitamin and mineral intake. The nutrients these calories and macronutrients provide can also greatly impact your success.

No mention of the food groups

The nature of flexible dieting is built on tracking your macronutrient intake, which neglects other important factors like the food groups. 

This is actually what I like my clients to consider: flexible dieting plus the principles of MyPlate and consuming a variety of fruits, vegetables, whole grains, lean protein, and low-fat dairy. 

Restrictive 

Although tracking and self-monitoring can effectively aid weight loss, it may not suit everyone. Some individuals may find the macronutrient targets and calorie budget limiting, particularly those who have experienced eating disorders.

If you are still on the fence about flexible dieting, consider reading the pros and cons of counting macros.

Final Thoughts 

I think flexible dieting can be a great tool for those looking to level up their nutrition. This method incorporates tracking, which can help you become more aware and a flexible approach to striving for your health goals. 

I often suggest a flexible dieting approach by paying close attention to my clients’ quantity of each food group. I find that this approach offers the most flexibility and compliance rate.

Noah Quezada is a Registered Dietitian Nutritionist located in Denver, Colorado. Over the course of more than a decade, he has gained extensive experience in helping clients manage their weight through in-person sessions. Noah is also the 2023 President of the Colorado Academy of Nutrition and Dietetics.