Can fat be healthier than thin? How to actually measure your fitness.

We are used to listening about obesity rates, and how obesity is related to heart disease risk and all sort of other diseases. At the same time, the media swamps us with images of thin, happy people. It seems that if you are fat, or overweight, you are doomed.

At the same time fitness is associated with thinness. To be fit, you got to be thin. To be super-fit, you got to be ripped.

All this seems like common sense. But is it really true, or is it another example of common misconceptions?

Let’s start with the gentlemen in the picture on top. I found their story in Dailymail.

I will give you the BMI of both of them, and then I will to ask you to guess who is the healthiest.

What is BMI?

Body Mass Index, or better known as BMI, is a way to measure whether your weight is normal, too low, or too high. It connects your height with your weight.

It’s calculated as weight (kg) / height² (m). [If you don’t like math, here is a great online tool to calculate your own BMI.]

For example, if you weigh 70 kg and have a height of 1.75 m, then your BMI is 70/1.75² =22.9 .

Then, according to the chart below your score of 22.9 falls in the normal category. So your weight is in the perfect range!

Let’s get back to the fat vs. thin guy story.

The thin guy on the right has a BMI of 22.5, thus he is in the healthy range. The guy on the left though, has a BMI of 41.5 – oops, he is in the obese class III!!!

So now it’s your turn to guess who is healthier: the thin guy or the fat guy?

I would say it’s the thin guy.

Well, it seems that I am wrong…

According to the story in Dailymail, the fat guy has a healthy blood pressure, healthy glucose levels, a healthy liver, and healthy lung capacity.

Contrary, the thin guy has a high blood pressure, high cholesterol levels, and his liver function and blood sugar levels are close to the unhealthy range.

Surprised? Me too.

How can a fat guy be healthier than a thin one?

The mystery is easy to solve – the fat guy has a lot of exercise, while the thin guy does not exercise at all (and at the same time drinks a lot).

You see, weight and even fat, cannot measure alone whether someone is fit and healthy or not.

There are plenty of scientists that have criticized the use of BMI as a good metric of health, including Prof. Kite Lindsay. In her paper on the definition of health, she explains that it’s cardiovascular fitness that brings health benefits, not weight loss (of course, weight loss is beneficial if it’s also accompanied by cardiovascular benefits).

And guess what…To be fit, you need to exercise or at least…move! You don’t necessarily need to lose weight. You could lose weight if you wanted to, and it may happen to you if you start exercising, but being fat does not necessarily mean you are not healthy.

Mirror, mirror, how fit am I?

You look yourself in the mirror, and deep inside you come to conclusions about your fitness or health level. You may think you are out of shape just because you are not as thin as you would like to be.

But now you know that being fat may not necessarily mean that you are not in shape.

At the same time, assuming that you already have a healthy weight, you may think that you need to be ripped to be super-fit.

Let me tell you – that is not true. Being ripped is largely dependent on nutrition (and genes). This means that…

Two people may be equally strong, and have similar endurance, but one of them may look “fitter” than the other.

The fitter-looking person may eat better or may have a different body structure than the other person. However, they are equally fit despite appearances.

At the same time having extremely low fat percentages may not be even healthy for you. E.g., women with body fat percentage lower than 13% may start missing their periods (but yes, they are totally ripped!).

So, looking pretty does not mean that you are healthy, and being healthy does not mean that you will look awesome.

This is just how things are.

Really, how fit am I?

Since you cannot measure your fitness level with weight and looks, then how can you tell how fit you are…?

1. Measure your resting heart rate.

Your resting heart is you heart rate when you are at rest – e.g., when you are lying down but are not sleeping, and were not exerting yourself recently. A good moment to measure it is in the morning when you wake up.

To measure it you need to measure your pulse by putting two fingers (index and middle finger) on your wrist or neck. If you feel your heart beating then you are ready to move forward.

Get a watch (or use an online stopwatch) and start counting your beats for 15 sec. Then, multiply the result by 4 to get the total beats per minute. This will give you your resting heart rate. It will probably be between 60 and 80 bpm.

The lower your resting heart rate the fitter you are: The higher your cardiovascular fitness, the higher your system’s efficiency, and the less times your heart needs to beat.

However, this is a way to measure your fitness progression – e.g., when you first start exercising you may have a heart rate of 80 bpm, and then after one year of exercise you may go down to 70 bpm.

You should not use your heart rate to compare against the heart rates of your friends and then try to conclude who is fitter. This would be like comparing apples to oranges.

Also, keep in mind that your resting heart rate is largely dependent on your state when you measure it. E.g., if you are worried about something this will show up in your measurement! So, make sure you count your beats in a moment when you are really calm and serene.