What is Body Fat?

Reducing body fat is one of the most popular topics in health and fitness. Almost universally, people want less fat in their body than they currently have.

However, not everything about fat is bad. Body Fat is an essential part of your body composition. It is critical for maintaining body temperature, cushioning joints, storing energy, and protecting internal organs. Yes – your body does require fat.

While fat is necessary, too much or too little fat is unhealthy. Fat levels outside of normal ranges can damage your health in a number of ways: high blood pressure, heart disease, type 2 diabetes, and even certain cancers, to name only a few. Too little fat is also a problem: low energy, osteoporosis, and possible infertility in women.

Where Does Body Fat Come From?

Whether eating, sleeping, exercising, or just being alive, your body needs energy.

We get energy from what we eat and drink, commonly referred to as “calories.” A calorie is a unit of measure for the amount of heat needed to raise the temperature of one gram of water by one degree Celsius. Related to energy for our body, these calories provide the heat (energy) so that our bodies can function. Importantly, our bodies have the ability to store unused calories for fuel later.

Depending on a variety of factors such as age, weight, genetics, muscle mass, and activity level, your body will require a set number of calories/energy. If you consume the exact number of calories your body requires, everything you eat and drink will be converted straight into energy – this is the perfect (yet highly unlikely) scenario.

If you consume more energy than you burn, your body will store these excess calories as fat. If this stored fat is not converted into energy later, it creates excess body fat.

How Much Fat Do I Need?

It is simply not possible to function at 0% fat, or anywhere close to that. So that begs the question – how much fat do I need?

The appropriate way to evaluate this level is body fat percentage. Your body fat percent is the proportion of body fat mass to total body mass. Body Fat Mass, a less important metric when viewed in isolation, is the actual weight of fat in your body.

In the following images, we show the recommended body fat percent ranges for both males and females. Looking at the ranges, blue is underfat, green is optimal, yellow is overfat, and red is obese.


There are a few important tidbits from the above graphs.

First, notice that the ranges are different between men and women. In general, women’s bodies can support slightly higher fat levels. This is primarily because women need more fat to reproduce. All else being equal, women can safely hold a slightly higher percentage of fat in their body.

Second, notice that healthy fat levels change with age. As we grow older, it is normal to hold slightly higher fat levels. In many cases, individuals will have less muscle, resulting in a higher mix of fat. It’s equally important to notice that the disparity by age is not huge.

And third, remember that there is an “underfat” category. The idea is to be in a healthy range – not 0%. Ever notice that some of the best athletes in the world may look a little “soft” at times? These athletes need fat, and are trying to maintain optimal performance levels. While minimal levels of fat are more visually appealing to some, it is not always that healthiest approach.

How Do I Know My Body Fat?

Now for the fun part! Understanding body fat requires an analysis of your body composition. 

Not all Body Fat is Created Equal

Looking at your complete body composition is important. Do you have too much /too little fat? Do you have too much / too little muscle? Does the segmental analysis reveal a weakness in a specific spot? Just knowing your body fat percent isn’t enough. 

 Where your body fat resides is critical. One of the most important readings is Visceral Fat. Visceral Fat is fat surrounding organs, and is the most dangerous to your health. Even at low levels of body fat percentage, too much visceral fat can pose serious problems. While individual fat can’t be specifically targeted (unlike muscle), knowing that visceral fat is too high can help someone keep pushing fat levels lower even if they are in the “healthy” range.

Final Thoughts

Body fat is not just related to your beach body. It is a critical component of your total health.