How much should you eat to lose weight: A scientific method for calculating calorie intake during dieting

How Much Should We Eat?

For those not trying to lose weight, the calories they consume daily should be sufficient to meet their daily energy needs. However, for those trying to lose weight, they only need to eat enough to meet their minimum requirements for health. So, how much should someone eat at the very least to lose weight healthily?

A fan once asked me if it was okay for her to eat 800 calories a day to lose weight quickly, as she was going to be a bridesmaid at her best friend's wedding. I didn't recommend it because 800 calories certainly wouldn't meet her minimum requirement. But she said she felt full and not hungry. I told her: whether you've eaten enough isn't measured by whether you feel hungry or not; there are more scientific calculation methods to measure it.

Regarding calorie intake, the World Health Organization recommends that an average adult woman's daily calorie intake should not be less than 1200 calories, otherwise it will affect her health, leading to insufficient energy for bodily organs and malfunction. The American College of Sports Medicine recommends that an average adult woman create a calorie deficit of 500-600 kcal per day, meaning her daily calorie intake should be 500-600 kcal less than her daily calorie expenditure. If we calculate based on an average adult woman's daily calorie expenditure of 1800 kcal, then her daily calorie intake should be controlled at 1200-1300 kcal.

From this perspective, the recommendations from both sources are similar. Therefore, if you are a 1.6-meter-tall, 60-kilogram adult woman, consuming around 1200 kcal of food per day will help you maximize your weight loss.

Here's a crucial question: not all women are 1.6 meters tall and weigh 60 kilograms. So, should women who are 1.5 meters tall, 1.7 meters tall, weigh 65 kilograms, and weigh 100 kilograms still plan their diets according to the 1200 kcal standard? Clearly, this is incorrect. Because women of different heights and weights have different daily energy and nutritional needs, their minimum calorie requirements for weight loss will naturally differ.

A woman with a minimum calorie requirement of 1000 kcal who tries to lose weight by consuming only 1200 kcal per day will inevitably experience slower weight loss. Conversely, a woman with a minimum calorie requirement of 1500 kcal who tries to lose weight by consuming only 1200 kcal per day will inevitably experience insufficient calorie intake. While this may result in slightly faster weight loss, it will negatively impact her health and, consequently, the overall progress of her weight loss efforts.