How to calculate your body's calorie needs - Fit & Flourish (2024)

By Fawn on February 18, 2021

How many calories do you need?

There are many factors that determine your calorie needs, and every individual is different. Although I don’t recommend counting calories as an ideal method for long-term weight loss, it’s good to get a general idea of how many calories your body needs per day for weight management.

Just remember that this will only provide an estimate, and individual needs may vary. It is also important to consult with your health care provider before making any decisions regarding your diet.

Having an estimate of your calorie needs, in combination with a good understanding about the calories (energy) in your food, is important for learning how to navigate food choices. This chart helps determine the average number of calories per day required to maintain your current weight. It will also help you figure out how many calories are needed for healthy weight loss or gain, if that is desired.

One more thing to note, tracking calories for a short time as a learning tool is something I highly encourage. However, I don’t advise doing so long-term for many reasons. Counting calories can feel restricting and is very difficult to maintain as a weight loss method over time. Furthermore, it may create anxiety around food choices, possibly causing more harm than good.

Weight loss is attained through being in a calorie deficit. Hence, the calories your body uses throughout the day and night must be greater than the amount of calories you eat. With that said, what you eat is just as important. It’s imperative to maintain a calorie deficit without over restricting (eating too little). This can lead to various health problems, such as malnourishment, vitamin deficiencies, weakened immune system, and reduced fertility, among other things.

The foods you eat will also greatly impact your health. When observing calories for weight loss, foods that are lower in calorie density (such as fruits, vegetables, lean protein, and whole grains) are often healthier choices than high calorie dense foods (like candy, chips, oils, or fatty protein sources). Read here to learn more about calorie density and how it relates to weight management.

How to calculate your body’s calorie needs (two ways)

Calorie Calculator

This Calorie Calculator does the work for you, simply enter your information and it will quickly give you an estimate of your calorie needs. Optionally you can use the formula below. Both are based on the Mifflin-St Jeor Equation.

Calorie Formula

_{The following chart is based on Mifflin-St Jeor Equation converted to imperial measurements. Since energy needs differ among men and women, there are different calculations for each. This is designed for healthy men and women, ages 19 years and older.}

Step 1: Determine your REE (Resting Energy Expenditure)

Calculate your Resting Energy Expenditure using this formula:

Men:REE = (4.536 x weight in lbs) + (15.88 x height in inches) – (5 x age) + 5
Women:REE = (4.536 x weight in lbs) + (15.88 x height in inches) – (5 x age) – 161

Example:
Woman: 150 lbs, 5 ft 5 in (convert to 65 inches), age 34
REE = (4.536 x 150 lbs) + (15.88 x 65 inches) – (5 x 34 yrs) – 161
REE = 680.4 + 1032.2 – 170 – 161
REE = 1381.6

Step 2: Select a Physical Activity (PA) Factor

Choose a Physical Activity Factor based on your activity level throughout the week.

Step 3: Determine TEE (Total Energy Expenditure)

Multiply REE (step 1) times PA Factor (step 2) to obtain the estimated TEE (calories per day) to maintain weight.
REE (step 1) x PA Factor (step 2) = TEE

Example:
REE (1381.6) x PA Factor (1.375)
1381.6 x 1.375
TEE = 1899.7
(Estimated calories per day to maintain weight)

Step 4: Adjust Based on Your Goal

• If weight loss is desired, subtract 300 – 500 calories per day to obtain adjusted caloric intake required to achieve weight loss of approximately 0.5 – 1 pound per week.
  
• For maintenance, use your TEE (step 3) to base your caloric intake on.
  
• If weight gain/bulk is your goal, add 300 – 500 calories per day to obtain adjusted caloric intake required to achieve weight gain of approximately 0.5 – 1 pound per week.

Example:
TEE (1899.7) – 500 calories per day
Adjusted amount: 1399.7
(Estimated calories per day to lose one pound per week)

**Remember to monitor your results for at least one month, and adjust your calories if necessary. If you are interested in tracking your calories for a short time period, try the free version of the My Fitness Pal app.

_{The information provided in this post is for informational purposes only and is not intended to serve as a substitute for medical advice. Contact your health care provider before making any decisions regarding your health and diet.}