Using RMR to Optimize Your Diet for Fat Loss
To determine a daily caloric intake target for safe and sustainable fat loss, you need to consider your resting metabolic rate (RMR) as well as your daily caloric burn from your normal activity level. To do this, you need to calculate your Total Daily Energy Expenditure (TDEE) using your RMR.
You should NOT target your RMR as your caloric intake in order to lose weight or fat. Your RMR is your minimum caloric threshold needed in order to maintain bodily functions. Eating at or below that rate can force your body into a dangerous and unsustainable “starvation mode” that is not only harmful but can also reduce your metabolism (potentially permanently), increase your hunger, and hamper your ability to lose weight.
Determining your Total Daily Energy Expenditure
Your Total Daily Energy Expenditure (TDEE) is an estimation of how many calories you burn each day, including physical activity. This is simply your RMR plus the calories you burn from physical activity and is easy to calculate based on your activity level using the chart below.
|Amount of Exercise/Activity||Description||TDEE Calc|
|Sedentary||Little to no exercise||RMR x 1.2|
|Lightly active||Light exercise/sports 1-3 days/week||RMR x 1.375|
|Moderately active||Moderate exercise/sports 3-5 days/week||RMR x 1.55|
|Very active||Heavy exercise/sports 6-7 days/week||RMR x 1.725|
|Extremely active||Highly physical job or very hard exercise 6-7 days/week or training twice a day||RMR x 1.9|
Your RMR makes up around 60 - 75% of your TDEE.
Using TDEE to lose weight
TDEE is what your body requires in a day to maintain your current weight. If you want to lose weight and fat, you need to consume less than your TDEE.
How much less should I eat?
Most experts agree that reducing calories by about 10 - 20% from your TDEE is optimal and safe. Reducing by more than 20% can lead to muscle loss and other negative outcomes.
What you eat matters
While your total caloric intake is important for weight loss, what you eat and the nutritional content of those calories are also very important for body composition (e.g. fat loss and maintaining muscle). Pay attention to macronutrients (protein, carbs, and fat) and eat enough micronutrients for your body composition goals, to sustain the weight loss progress.
Cutting sugar and non-nutritious foods and maintaining adequate protein and healthy fats are very important when trying to lose fat while maintaining muscle.
Importance of exercise for fat loss
You can achieve weight loss with diet alone but if you want to reduce fat mass, maintain muscle mass, and in turn, more effectively decrease your body fat percentage, you need to eat better AND exercise appropriately.
The types of exercise you do can also impacts how your body burns calories. While cardio exercise can directly target fat loss, resistance training helps build or maintain muscle that burns calories throughout the day when you are not working out. This is because muscle is calorie-burning and increasing your lean mass can actually increase your base metabolism.
Remember to factor in your exercise program into your TDEE so you are matching your caloric needs appropriately.
Remember other lifestyle factors
Other lifestyle factors such as poor sleep quality and high stress levels can negatively affect fat loss because they create a hormonal environment that requires you to store more energy to support holistic body function.
To efficiently lose fat, especially if you have plateaued, addressing sleep and stress is important.
We also recommend working with an experienced coach to help determine your macronutrient needs and appropriate exercise program to achieve your body goals.