Is WEIGHT LOSS different from FAT LOSS?
Updated: Oct 26, 2021
The terms weight loss and fat loss are often used interchangeably. However, scientifically, both are not the same. Weight loss can occur without significant fat loss or even with fat gain. Similarly, fat loss can occur with no weight loss or even with weight gain. Weight loss or gain may not matter if there is fat loss. Having said that, how is weight loss different from fat loss? Does weight loss and fat loss always result in a decrease in body weight? Let us use the power of science to understand Weight Loss and Fat Loss.
Is WEIGHT LOSS Different from FAT LOSS?
Weight loss occurring without or with minimal fat loss is very different from weight loss occurring because of fat loss. Yes, both may result in a decrease in the absolute weight of the body, but the way it happens in each case is very different. For example, weight loss can occur due to incorrect lifestyle or severe illness like dengue fever or diseases like HIV, cancer etc. or because of dehydration (typically seen on the weight scale after a steam/ sauna session).
Any weight loss (except weight loss occurring from dehydration) is a combination of muscle loss and fat loss. The goal of successful weight loss is to gain or preserve as much muscle as possible while losing as much body fat as possible. The body fat percentage is the correct indicator of a successful fat loss programme. In fact, with proper nutrition, exercise, and rest, we may weigh even higher than before but appear very compact due to muscle properties. Muscles are compact and dense, unlike fat. For example, 1 kg fat occupies way more space than 1 kg muscle. Here’s a blog on the fundamental differences between fat and muscle: What is the difference between Fat and Muscle?
Weight loss without fat loss may not even be noticeable. However, fat loss resulting in weight loss is impossible to go unnoticed.
Let us Try Understanding WEIGHT LOSS and FAT LOSS with the Help of an Example:
Consider the following two cases for a 100 kg person:
Total weight lost: 20 kgs.
Muscle lost: 15 kgs.
Fat lost: 5 kgs.
Total weight lost: 20 kgs.
Muscle lost: 1 kg.
Fat lost: 19 kg.
Although both cases result in a weight loss of 20 kgs, case B is a clear winner as 19% weight is lost from fat loss, and only 1% weight is lost from muscle loss.
Fat hangs, giggles, wobbles, and occupies a lot of space. On the other hand, muscle does not giggle, wobble and is compact, dense, and occupies less space.
The Incorrect BODY MASS INDEX Measure:
Body mass index works for the majority sedentary population but for others like athletes, sportspersons and people who lead an active lifestyle, it may not work. Let’s consider the following example:
John is 5.11 and leads an active lifestyle. Weightlifting is his passion. At his peak, he was 107 kgs with 8% body fat. Unfortunately, John had to stop training due to an accident. Today, he is 68 kgs with 16% body fat. If one had seen John’s body mass index at his peak, one would have classified John, with a body mass index of 32.9, as obese (a BMI above 30 is obese). On the body mass index scale, he was obese, but in reality, he was super fit with dense muscle and less fat. That is why body mass index may not work for people who live an active lifestyle.
With the above example, it’s clear that something more than just our weight and height needs to be assessed to classify us as obese. In reality, we only need to know the body fat percentage to check for obesity. Body fat percentage is the total fat mass divided by the entire body mass and multiplied by 100. Most modern gyms have a fat percentage calculating machine. Enquire at your gym if they have one. Body fat percentage is one of the five pillars of fitness.
A Male has an Ideal Body Composition if no more than 15% of his overall body weight comprises ADIPOSE TISSUE (fat).
A Female has an Ideal Body Composition if no more than 20% of her total body weight comprises of ADIPOSE TISSUE (fat).
Weight loss occurring due to fat loss is way different from weight loss occurring without significant fat loss.
We should always focus on fat loss and disregard weight loss.
Weight loss may or may not occur due to fat loss (if muscle weight increases more than the fat weight lost, the total body weight will increase).
Fat loss is always healthy. However, weight loss can be beneficial only if fat loss is significantly more than muscle loss.
Now we understand how weight loss is different from fat loss and why fat loss is a more accurate measure to assess the success of our fat loss programme.