The Different Tests for Measuring Body Fat

The best way to measure your body fat is with a test at a gym or medical center, that measures you directly. There are lots of new gadgets and scales that calculate your body fat, but these are generally less accurate than having it measured professionally.

The simplest and cheapest way to measure your body fat is the skin fold test. You can purchase a set of calipers for around $20 dollars, and do this test in the privacy of your home. Calipers are used to pinch you skin in different areas. The results are entered into a formula to determine your body fat. It can be very accurate, but usually is not. It depends on the skill of the person who is using the calipers. If they are separating your fat and muscle and finding the right spots to pinch.

The most accurate way to measure body fat is to weigh someone underwater. This is known as Hydrostatic weighing. You sit on a scale inside a tank of water and blow out as much air as you can. You are then dunked underwater, where you blow out any remaining air. Since fat is lighter than water, the more fat you have the more you will float. With a margin of error around two to three percent, this is one of the more accurate tests. It can be a difficult way to measure body fat since it can be uncomfortable and even scary to be dunked underwater with no air in your lungs.

Dexa (dual energy x-ray absorptiometry) is used to measure bone density, and body fat percentage as well as where most of the fat is located. Dexa uses a whole body scanner and two different low dose x-rays to read bone mass and soft tissue mass. The procedure takes between ten and twenty minutes. It is a painless, gold standard for measuring body fat, and has a high degree of precision with a two to three percent margin of error.

bioelectrical Impedance is one of the quickest ways of testing body fat. Either using a hand held scale or standing on a BIA scale, a signal passes either from hand to hand or foot to foot. The faster the signal travels, the more muscle you have. The results are based on the fact that water conducts electricity. The results are affected by hydration, skin temperature and food intake. If you are dehydrated your body fat percentage will read higher than it is. Test at the same time of day, preferably first thing in the morning before breakfast, but after a glass of water. The margin of error for this test is four percent.

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