It must seem impossible.

You try to lose weight by eating as clean as possible, yet someone else can lose weight and body fat while only eating McDonald’s for a whole month.

This story in the Independent was about a man who ate only McDonald’s for one whole month and actually got leaner.

How did it happen?

Why is that possible?

And if it can be done, why are we stuck eating salads?

Well, let’s see how it worked and why it probably isn’t the best option.

Calories In - Calories Out

If you follow this golden rule you will lose weight.

If you burn more calories than you eat, you will lose weight.

Now admittedly, this is very simplified and it isn’t as easy as it sounds.

However, if you count calories and eat less than you burn you will lose weight.

That is the basis of how this experiment worked.

The guy ate only McDonald’s, but he only ate 2500 calories and actually reduced it to 2300 calories after a few weeks.

That means if he on average burns 2500 calories per day, he is eating less and so loses weight.

Then he spent an hour in the gym every day so burned extra calories and lost more weight.

So even if you do eat McDonald’s for every meal, if you track your calories you should still lose weight.

Speedy Metabolism

Calories in vs calories out is definitely king.

And when you have a speedy metabolism, it makes it even easier to burn those calories.

How did the guy eating McDonald’s every day lose weight?

He was burning more calories than he ate.

A big part of this was that he was already a fit guy.

Having been a bodybuilder, he had a lot of muscle tissue meaning he burns more calories throughout the day than most other people.

That makes it easier to lose weight when on a calorie restricted diet because his daily activity alone probably burned more than 2500 calories per day, never mind the time spent in the gym too.

This will have made it easier for him to lose weight than most others anyway.


Although he may have lost weight, a diet of McDonald’s every day is not going to do you much good.

Yes, eating fewer calories will help you lose weight, but that shouldn’t mean you just eat anything.

If all you eat is McDonald’s, you aren’t filling your body with the good stuff you need.

That means it’s probably not going to be the best for your heart or body in general.

Where are the vegetables (and no, pickles and tomato sauce don’t count)?

In the short-term, you could lose weight (calorie dependant) but long term it is not going to do you any good.


One of the major problems with this diet is the volume of food.

Eating 2500 calories is like 2 Big Mac Meals - and they are not even that big.

Imagine eating two meals and that being all you can eat for the day…

Then compare that to four healthier 600 calorie meals and you could eat more than twice as much yet consume a similar amount of calories.

Volume is a major part of losing weight.


Well if you feel hungry you are going to eat more.

Eating just too meals is going to make you want to eat more through the day, meaning you eat more calories.

Eating 3 or 4 smaller meals will mean you spend less time feeling hungry and so have less chance of eating more and more.

Over a day, that can mean you eat fewer calories and so lose weight without having to resist your hungry tummy.

So would it work for you?

Like I said at the beginning.

If you eat less than you burn you will lose weight.

So would this diet of McDonald’s work for you?

Well maybe, if you ate fewer calories than you burned.

However, it would be a struggle since you would only be eating a smaller amount of food every day.

Plus, it wouldn’t be very good quality food, which usually causes you to have even more cravings.

So when you are hungry and craving bad food, it is not going to help you lose weight.

What I’m saying is that this diet could work, but it isn’t going to be easy and it isn’t going to be much good for you in the long run.

You are better making dietary changes like -

  • Eating more vegetables

  • Eating more lean protein

  • Don’t eat naughty foods as often

That way you feel full and consume fewer calories without compromising your health.

Lose weight eating McDonald's