I think this is a topic which seems basic enough, but is actually a lot more confusing than most people give credit. The majority of adults want to lose “weight”, and while some can differentiate between losing fat mass vs. muscle mass, it’s a complicated process to figure out. Your BF% is a difficult number to find, the more common tests can give you a general idea, but it’ll likely never be completely accurate (unless you have access to some high tech kinesiology lab equipment and a team of experts).
So, let’s talk a little bit about body fat and what different percentages look like.
A Necessary “Evil”
The bottom line is that we all need a certain amount of body fat, and this amount differs between males and females. Essential body fat percentage for men is about 2 – 5% and 10 – 13%for women – the difference is due to hormonal factors and the potential demands of pregnancy. These levels are necessary for the body to function at a pretty minimum level. Just ask a bodybuilder how they feel at their stage weight – it’s not great. So, while they can get through basic life demands, these low levels could not be maintained for long.
Fat is responsible for a number of things in our bodies, which is why your diet needs to have an adequate intake of healthy fat sources. Some key functions of fat include:
- Protects internal organs
- Provides energy
- Regulates hormones
- Regulates body temperature
- Promotes cell health and provides cell structure
- Assists in vitamin absorption, which impacts the health of our skin and hair
Body Fat % vs. BMI
A fair amount of confusion comes from these two measurements – they are definitely NOT the same thing! Your BF% is the percent of fat mass you have compared to everything else in your body (muscle, bones, organs, water, etc.). It’s calculated by dividing your fat mass by your weight (to give you a percentage).
Your Body Mass Index (BMI) is a ratio of your height and weight (total weight – not fat mass). This is a very general tool used for basic health screening principles amongst *most* people. Things to be aware of – this is NOT a good measurement tool for individuals who carry a lot of muscle mass (as this increases your weight, increasing your BMI result, but is healthy weight), pregnant women, elderly people, and children. Think of this – your BMI will be the same if you’re 200lbs of sexy muscle or 200lbs of cupcakes… or hot dogs!
A reliable BMI can be calculated by a number of tools online, as all you have to do is enter your height and weight. On the other hand, your BF% is much more difficult to calculate and requires special tools, ranging from something basic like calipers to a hydrostatic weighing machine.
Beyond the fact that a certain amount of body fat is necessary for survival, here are some guidelines of body fat percentages:
While you can clearly see how different the numbers are for men and women, I think these pictures are far more helpful to put it into perspective:
Keep in mind:
Having a low body fat percentage doesn’t mean you’re healthy! Those individuals at the incredible low body fat rates are only keeping that for a short period of time (such as a competition or photo shoot). In order to reach that low of a level, you have to be incredibly strict and 100% consistent with your nutrition and training. Additionally, keeping your body fat that low for a prolonged period of time can have negative impacts on your overall health, such as a weakened immune system, hormonal imbalances, and exhaustion to name a few. This is why bodybuilders and fitness models transition to off-seasons, where they return to a more sustainable body fat percentage.
People tend to store fat differently, but in general women store it in their hips and thighs, while men store it in their mid-section. Men are at a disadvantage here as fat stored in this region is a far greater health risk for developing chronic diseases.
Changing your body composition by increasing your lean muscle mass will make a huge difference in how you appear. Simply losing body fat won’t give you that athletic, fit appearance if you haven’t built the muscle mass. If you want to see the definition and curves, hit the weights!