I’ll start by saying there's no easy or precise answer to how many calories anyone should eat in a day. Your fuel needs differ per personal metabolism and body composition. Additionally, activity level, stress levels, hormones, sleep, and more all play a part, and counting calories may or may not be a helpful addition to other habit changes. the old adage “calories in, calories out” is by no means the whole picture, but it is a piece of the puzzle. Think of caloric currency as intel. You can't improve if you don't have a baseline to start from.
All calories are not created equal. By definition, all calories represent units of energy provided by a particular food, but thinking they’re all alike is like saying one of my favorite expressions, a diamond and a rhinestone are the same because they both glitter. With calories, as with diamonds, the quality matters most and enhances their value. Nutrient dense, real food with sufficient protein, quality fiber filled carbohydrates and healthy fats is always the way!
Some people dislike or are triggered by keeping track of numbers. If that’s you, that’s A-OK. Take what works and leave the rest. Experts all agree that counting calories is not the be-all, end-all of living your healthiest life, even when it comes to weight loss.
That said, some people like numbers and data tracking, so here is info about how to best gauge your caloric needs.
Start by getting an idea of your basal metabolic rate (BMR). The basal metabolic rate is the minimum number of calories your body burns at rest, the number of calories required for involuntary functions such as breathing, regulating body temperature, digesting food, and keeping your circulation going. Think of this as the number of calories you would need to keep your body alive if you were merely to stay in bed all day watching Netflix.
The most accurate way to calculate your BMR is to go into a lab. They can measure the amount of carbon dioxide you're expelling and how much oxygen you're breathing to see how efficiently your body metabolizes calories.
Don't have time for that? You can calculate your resting metabolic rate using the Mifflin-St. Jeor equation or the Harris-Benedict equation below. Some of them have built in Total Daily Energy Expenditure (TDEE) and give you a general number for weight maintenance, loss or gain.
Harris-Benedict equation will be useful for all but the very muscular (it will under-estimate calorie needs) and the very overweight (will overestimate calorie needs).
This equation (below) has a built in Total Daily Energy Expenditure (TDEE).
The general recommendation for weight loss is to create a calorie deficit which is appropriate. Be aware that most people over estimate their exercise. Don’t think of exercise as a way to eat more on a consistent basis.
Tracking macros, (how much protein, carbohydrate, and fat you need for your goals) takes a step further will be covered in our next blog!
These are all valid and useful ways to gain caloric needs and expenditure information. Just keep in mind that all of these numbers—how many calories you supposedly need, how many calories various activities allegedly burn, how many calories food contains—all of these are just estimates. You, my friends, are not merely a number.
Your calories should never dip below 1,200 as your body will assume it’s starving, and your metabolism will adjust accordingly.
Your BMR will increase as you gain muscle.
Equations that consider your gender, height, weight, age, and activity level can give you a ballpark number, but don’t stop there—track your food and note how your weight responds and how you feel.
One of my favorite quotes is by Dr. Sharma, “A patient’s best weight is therefore whatever weight they achieve while living the healthiest lifestyle they can truly enjoy.”