Back to Basics
So far in this series we have talked about calories and how your metabolism works. So now, let’s see how those concepts affect our body fat and why it matters where we store it. We all know that how much fat we have matters to our health. But do we know why, how much is ideal, and that where we store it matters? Let’s break this important concept down to the basics, shall we?
How Does Fat Accumulate?
We know from previous weeks thats calories are the logs fueling our fire and that our metabolism is the fire that burns up the fuel. So, what happens when we aren't burning through our firewood quite as quickly as we thought? It starts to pile up right next to our fire so we can use it later when we need it.
That's exactly how our bodies work. When we consume more calories than we burn, we store them for later - and the storage form of choice in our bodies: fat.
Our bodies are always interested in storing fuel for later in case we run out of food one day and need to tap into our own stores. So, the more we eat and the less we burn, the more fat accumulates to use as fuel some time down the road when we might need it. When we never challenge our bodies to tap into our stored fat, it stays put, right where it is and continues to accumulate as the cycle persists.
Now, we also know from previous weeks that the simple math of calories in/calories out does not always work as smoothly as we want. Some of the other factors to consider are quality of calories and our metabolism. But basically, that's the gist of how things works.
How Much is Too Much?
One way to measure your body composition (or, what you're literally made of), is by looking at the percentage of fat you have compared to your lean body mass. The amount of fat you have can be measured as a percentage of your total weight. The rest of your weight is made up of lean body mass (muscles, organs, etc.). The higher the percentage of fat you have in your body, the greater your risk for diseases like heart disease, diabetes, cancer, metabolic syndrome, etc, tends to be. Ideal numbers for men and women differ, and they do change as we age. But, here's a general breakdown of how much body fat we should aim for:
- Essential body fat (what you need to be healthy): 2 - 5%
- Athletes: 6 -13%
- General fitness: 14-17%
- Acceptable: 18-25%
- Obese: 25+%
- Essential body fat: 10-13%
- Athletes: 14-20%
- General fitness: 21-24%
- Acceptable: 21-31%
- Obese: 32+%
Why do those numbers matter?
We need fat to survive. It is essential for brain health, as an energy source, insulation and protection, some nutrient absorption, and hormonal production. We just need to be careful to keep it in a healthy range or we can begin to see adverse effects.
The more body fat you have, the greater your risk for disease such as heart disease, diabetes, metabolic syndrome (and the list goes on) as you approach unhealthy levels. We learned last week that the more body fat and less lean body mass we have, the more likely it is that our metabolism slows down and works inefficiently, making it harder to lose weight. Keeping your total body fat in a healthy range with a good balance of lean body mass can help ensure that you continue to maintain optimal health.
Just as you can have too much body fat, you can have too little as well. Especially as women, we face adverse effects as we drop below the essential amount of fat we need to stay healthy, strong, and functioning properly. Drop below those numbers and you increase your risk of hormonal changes, fractures, fatigue, and vitamin deficiencies, among others.
Where It’s Stored Matters
So, we need fat, just not too little and not too much, and we need to be careful where we store it. Picture two people: one shaped like a pear, and one shaped like an apple. The pear-shaped person would have a smaller top and larger bottom with more fat accumulating in their lower body. This type of fat tends to be subcutaneous fat- or the kind you can grab in your hand.
The apple shaped person would have more fat accumulating around their middle. This type of fat tends to be visceral fat- the harder stuff around your middle that’s the dangerous kind.
Visceral fat is the stuff that sits in and around your organs, which can be dangerous. A higher amount of visceral fat has been linked to higher levels of LDL cholesterol (the “bad” kind), and lower levels of HDL cholesterol (the “good” kind), insulin resistance (which can lead to diabetes), and some cancers.
The good news: you can change it! You can bring your body fat back into a healthy range and increase your lean body mass by making healthy changes, working out, and eating a balanced diet. Thank goodness.
Basically: The amount of body fat you have and where you store it matters. You want to keep the balance of body fat and lean body mass in a healthy range.