What Is the Ratio of Calorie Deficit to Weight Loss

What is the ratio of calorie deficit to weight loss? The ratio, which was first set in 1958, is that to lose 0.45kg / 1 lb of weight in a week you need an overall calorie deficit of 3500 calories across that week.

Therefore, if you aim for a deficit of 500 calories per day you will lose 0.45kg / 1 lb of weight in a week.

Who discovered the ratio of calorie deficit to weight loss and when?

The ratio of calorie deficit to weight loss was first noted in a report produced by Max Wishnofsky.

The report was called the “Caloric equivalents of gained or lost weight,“

The reported stated that to burn 1 lb of fat you need to burn 3500 calories.

Conversely, the report also stated that to gain 1 lb of weight you needed to consume an extra 3500 calories.

This report was picked up and widely used by a number of notable dietitians and physicians over the decades.

As a result, it became widely accepted as an approximate ratio of weight loss to calories.

Who was Max Wishnofsky?

Max Wishnofsky was a Russian born Physician and Medical Researcher.

He was based in New York where he worked as a Medical Doctor with the Jewish Hospital in Brooklyn New York.

How did Max Wishnofsky determine the ratio?

Max determined the ratio by studying a large amount of previous written material and derived from this that the energy density of 1 lb of adipose tissue had an energy density of approximately 3500 calories.

Adipose tissue is the medical term for body fat.

How accurate is the ratio?

Overall, the ratio has been a useful guide to weight loss but its accuracy is questionable as it doesn’t account for many other factors such as metabolism, activity levels, quality of diet etc.

However, it is a good general rule of thumb to get you going with weight loss.

Is 500 Calories a Good Deficit to choose?

Building on the Wishnofsky ratio aiming for a calorie deficit of 500 calories a day is a good starting point for your weight loss journey.

However, the critical part is working out your starting point to apply the 500 calorie deficit to.

Essentially, how much energy does your body need to run today – this is called your Total Daily Energy Expenditure.

But don’t worry. I’ve made a calculator to make working this out easy.

More support to get Travel Fit and Lose Weight

This guide to the Wishnofsky rule has been created as part of a series of guides and tools to help you lose weight and get travel fit.

For more support in this area take a look at our Travel Fit Page.