When comes to body fat measurement, experts say both body mass index (BMI) and body fat percentage (BFP) are good methods to determine the amount of fat in your body, your health status and disease risk.
Let's look at each one to pass our verdict.
It's an equation that gives you a numerical rating of your health based on height and weight. If your BMI goes up, so does your risk of developing weight-related diseases, such as heart disease, type 2 diabetes, stroke and some cancers.
It's a broad, general measure of health risk (related to the above-mentioned diseases). It doesn't distinguish fat from muscle meaning it doesn't tell you anything about your own body composition - how much of your weight is fat and how much is muscles and tissue.
Hence, it may not reflect accuratlely the level of fat for some highly trained athletes who are overweight but not overfat and also for people who are of normal weight per BMI scales but who are overfat.
Below is the range of BMI number for adults:
Less than 18.5 - underweight
18.6 to 24.9 - Recommended
25 to 29.9 - Overweight
30 and above - obese
Body fat is normally expressed as “body fat percentage" or “body fat percent. "
To be precise, BFP is the amount of body-fat-tissue as a percentage of total body weight.
Say your total body weight is 150 lbs and you've 30 lbs of fat, your BFP is thus 20%.
The higher your BFP above the average levels, the higher your health risk for weight-related diseases, like heart disease, type 2 diabetes, high blood pressure, osteoarthritis and certain cancers.
Body fat assessment is more specific to your actual fat level and thus can provide a more accurate picture of your health.
So, how much fat is OK?
According to American Council On Exercise (ACE), the following range of body fat reflects your weight and health status:
Essential fat - 10 to 12%
Athletes - 14 to 20%
Fitness - 21 to 24%
Acceptable - 25 to 31%
Obese - 32% plus
Essential fat - 2 to 4%
Athletes - 6 to 13%
Fitness - 14 to 17%
Acceptable - 18 to 25%
Obese - 26% plus
Based on the above, what you should shoot for is a range rather than a magic number. And women can be and should be fatter than men as they've a totally different reproduction function and the higher fat in women supports that reproductive function.
There're several methods to measure body fat but not all measures of fat percentage are equal. Some methods have high margins of error.
The 2 most common methods used are skin fold measurement and bioelectrical impedence analysis.
In skin fold measurement, a trained personnel uses calipers to measure specific spots on your body. He/she then compares the measurements against a chart that estimates fat percentage. One thing about this method - its accuracy varies greatly based on the user's abilities.
Many home use fat percentage scales are based on the technology found in bioelectrical impedence analysis.
The margin of error for these 2 methods can be as high as 8%, plus or minus.
Other methods (like X-ray analysis, water displacement) are more accurate but they're much more complicated.
So, which is the body fat measurement method you can use?
I would say, in terms of ease of use, convenience and usefulness, I'd prefer to go for BMI. It may be “crude" but it gives you a good idea of your health risk quickly and easily.
Cecelia Yap is an avid exerciser and is the owner of the successful exercise and fitness website: http://www.perfect-body-toning.com
Due to her strong passion in exercise and fitness, she has actually learnt how to convert her passion into a money-making venture. She shows you how here: http://www.perfect-body-toning.com/my-passion.html