Body Fat

Measurements that tell us what kind of stuff your body is composed of can tell us quite a bit about your level of health, or health risks. One of the most useful numbers is your body fat percentage. In other words, out of the 100% of stuff that makes up your body (fat, bone, organs, water, etc.), just how much is fat?

There are a number of ways to measure body fat. Here are the most common and most accurate:

  • Skin Caliper testing – this involves someone taking pinches of fat from different areas of your body, then doing the math. Equipment is cheap, but training is necessary for good results. Any certified personal trainer can do this for you. Accuracy is good, but depends on who is doing the test.
  • Submersion – this is the gold standard of these tests, and involves dunking you in water while all the air is out of your lungs. Sounds fun, doesn’t it? You’d need expensive equipment AND training to do this, but it is occasionally available at your local rec center.
  • Electrical Impedance – these are the bathroom scales you can buy for about $50 that send a small electrical charge through your feet and measure the resistance. Accuracy isn’t as good as the other two, but you can do it on your own. Be sure to heed the health warnings that come with it.

Just like any measurement the number you receive from this is meaningless without some published table of norms. Fear not! Here is that table:

Body Fat Categories
Male Female
Very Lean <8% <15%
Healthy 8-12% 18-22%
Slight Risk 20-25% 27-32%
Moderate Risk 25-30% 32-37%
High Risk 30%+ 37%+


You’ll notice that the higher percentages mention being at risk for something. Here’s a list of those somethings:

Risks for having too much body fat:

  • Hypertension (high blood pressure)
  • Diabetes
  • Hyperlipidemia (excess fat in the blood)
  • Arteriosclerosis (hardening of the arteries)
  • Congestive heart failure (heart attack)
  • Respiratory Insufficiency (difficulty breathing)
  • Increased risk in surgery
  • Joint injuries

However, having too low a percentage can be dangerous as well. This will often happen in anorexics or people who are high level bodybuilders or endurance athletes.

Risks for having too little body fat:

  • Menstruation stops (women only, obviously)
  • Lack of protection around vital organs – fat pads and protects your many of your internal stuff.


Needless to say, the healthy range strikes the best balance for your health. If you can get there and stay there, your body will thank you in the long term because it will be less stressed, more energetic, and more efficient.