You may be surprised.
Very basic answer: Here is a calculator that can give you a rough estimate of how many calories you should eat based on your goals (gain weight, lose weight, stay the same weight).
You need to put in your age, weight, height, sex, and activity level.
BUT HERE'S THE THING, and it's super important: This calculator may not really work for you. So next up is an explanation about what this calculator is doing, and also 10 important things you should know about your metabolism and calories that can help you personalize this answer a bit better.
NBC / Via polytelis.tumblr.com
First, let’s talk about what it means to say you ~should~ be eating a certain number of calories per day.
That's referring to an ideal number of calories, based on a lot of different factors that are outlined below. There's no moral judgment attached to it, though. The number of calories anyone eats is a personal decision, and not at all a reflection of their intelligence or value as a human. You can and should do whatever you want with your body. This article is just meant to be a guide for people who may find it helpful in achieving certain goals.
It isn't for everyone, though. If you have a history of disordered eating, for example, you should work with your doctor to figure out what's best and healthiest for you to focus on when it comes to calories and nutrition and food. That might mean not thinking about calories at all. Again: It's personal.
FOX / Via wifflegif.com
OK. So if you do want to figure out how many calories you should eat, a good place to start is to determine your Basal Metabolic Rate, or BMR.
This isn't how many calories you should eat in a day! This is just step one: "BMR is how many calories you're burning if you're lying in bed doing nothing, having eaten nothing for the last twelve hours," Dr. Michael Jensen, endocrinologist, professor of medicine at Mayo Clinic, and body weight regulation and obesity specialist, tells BuzzFeed Life. It's the minimum number of calories your body needs to simply ~exist~ — basically, to keep your organs running. (Most people typically move a bit more than that, which is why you need to eat a bit more than this. More on that in a minute.)
There are a few different ways to calculate BMR, but most experts use what's called the Mifflin-St. Jeor Equation, New York City-based Dietitian Brittany Kohn, MS, RD, tells BuzzFeed Life. This equation takes into account your sex, age, weight, and height. It's different for men and women. It stands to reason that trans individuals who have NOT medically transitioned may be able to use these equations by choosing the sex that they were assigned at birth (so, a trans man who has not medically transitioned would use the female equation, and vice versa). Unfortunately, it's unclear how these equations apply to transgender individuals who have medically transitioned.
There's more information below (in #3 of the metabolism facts section) about how to get a better, more personalized sense of your metabolism without using the BMR calculator if you find that the calculations aren't helpful to you in achieving your goals.
CK
Here's the equation for men:
BMR = 10 x weight (in kilograms) + 6.25 x height (in centimeters) - 5 x age (in years) + 5
CK
