Macronutrients Don’t Matter: Comparison of 4 Weight Loss Diets

Macronutrient Analysis

The term “macro” refers to the amount of food needed to support one’s body weight. A person needs around 2000 calories per day to maintain their current size. That means that someone with a BMI (Body Mass Index) between 18 and 25 would need 1500 calories per day less than someone with a BMI over 30.

A typical American diet contains approximately 1800 calories per day. So, if a person consumes 2000 calories less than the average American diet, they will lose 1 pound per week. If a person consumes 2500 fewer calories than the average American Diet, they will lose 2 pounds per week.

And so on…

If you consume 3000 fewer calories than the average American Diet, your body will start losing muscle mass and you’ll gain fat. You may even die from starvation!

So, what does all this mean? What does it really mean to eat less or more than the average American Diet?

Well, let’s look at some examples.

Example #1: You have a BMI of 23 and you want to lose 5 pounds per month. Your daily caloric requirements are 2000 calories. Therefore, you need to consume 2400 calories less than the average American diet.

So, if the average American diet is 2000 calories per day, you need to consume 1600 calories per day. If the average American diet is 2500 calories per day, you need to consume 2000 calories per day.

The common myth is that fat people eat more than skinny people. This is only sometimes true, and the difference isn’t always huge.

But it would still be true that a skinny person would have to eat more than a fat person, right?

Well, if we use the numbers above, a person with a BMI of 23 who eats 2000 calories per day would be eating less than the average American diet. A person with a BMI of 23 who eats 1600 calories per day would be eating less than the average American diet.

Example #2: You have a BMI of 30 and you want to lose 10 pounds per month. Your daily caloric requirements are 1500 calories. Therefore, you need to consume only 1000 calories per day.

Now, in this example, a person with a BMI of 30 who eats 2000 calories per day would be eating more than the average American diet. A person with a BMI of 30 who eats 1500 calories per day would be eating less than the average American diet.

Hopefully, you can see that the numbers aren’t always what they seem…

But Wait, There’s More!

Macronutrients Don't Matter: Comparison of 4 Weight Loss Diets - GymFitWorkout

There is yet another catch to all this. And this one deals more with non-scale victories (NSV) than anything else. Let’s take the first example, where a person wants to lose 5 pounds per month with a BMI of 23.

That person needs to consume 2400 calories less than the average American diet (which is 2000 calories).

The average caloric intake for a woman is 2000 calories per day. So this particular woman is 1000 calories below average…or half of what she should be eating.

However, there is no rule that says she must eat all her calories in one sitting. She could easily split that into two meals of 700 calories. Or three meals of about 400 calories each.

Or maybe she eats 2000 calories every day but just eats less than the recommended amount (but still more than our second example).

What this means is that people often lose weight on diets they claim to be “eating whatever I want.” This is true of every diet that allows you to eat less than the recommended amount of calories. Even very low-calorie diets (VLCDs) allow you to eat more than you need to lose weight.

So, ultimately, this is why people claim to be “eating whatever I want” and still losing weight. They’re not lying; they genuinely are eating whatever they want. They’re just choosing to eat much less of it.

And that’s perfectly fine. As long as it’s working, there’s no reason to fix something that isn’t broken (your beliefs).

The Myth of “Starvation Mode”

Macronutrients Don't Matter: Comparison of 4 Weight Loss Diets - GymFitWorkout

This is a myth that I’ve already debunked in a previous article, but since it’s relevant here, we’ll discuss it again. Starvation mode is a term used by people who believe that if they eat too little, their body will go into “survival mode” and ultimately hold onto every single calorie that they eat as stored fat, making it nearly impossible to lose weight.

What happens is that your body will lower its basal metabolic rate (the amount of energy it needs on a daily basis) and thus you’ll require fewer calories to survive. This can be combated by increasing your exercise.

Sources & references used in this article:

Macronutrient composition and food selection by JP Flatt – Obesity research, 2001 – Wiley Online Library

Concentrations of macronutrients, minerals and heavy metals in home-prepared diets for adult dogs and cats by V Pedrinelli, RVA Zafalon, RBA Rodrigues, MP Perini… – Scientific reports, 2019 – nature.com

Dietary management of the metabolic syndrome beyond macronutrients by DM Minich, JS Bland – Nutrition Reviews, 2008 – academic.oup.com

The China study: the most comprehensive study of nutrition ever conducted and the startling implications for diet, weight loss and long-term health by TM Campbell II – 2004 – books.google.com