by Sandra Piddock

Created on: April 18, 2010

The Body Fat Index is a recommendation table of healthy body fat levels. While stepping on scales will tell you if you are overweight compared to people of similar age, gender and height, it cannot differentiate between lean muscle and fat, and it's this lean-to-fat equation that offers the best indication of whether your weight is unhealthy or not.

Body fat percentage is calculated using height, gender, weight, and some body measurements. The required measurements are: waist, measured at the narrowest point and also the navel, hips, measured at the widest point, and neck, measured at the narrowest point.

Genetically, women carry a higher percentage of body fat than men in preparation for pregnancy. As the body fat index differentiates between the sexes, it can be a more accurate measure of healthy weight than the Body Mass Index (BMI). Athletic women will have a lower body fat percentage, as exercise builds muscle mass, which replaces fat. These women may have a body fat percentage of less than 18% and still be considered healthy.

Women need a minimum of around 12% body fat simply to maintain the body, and a healthy body fat ratio for a 20 - 40 year old female would be between 21% and 33%. More than 33% is considered overweight, while more than 39% body fat counts as obese. Due to differences in metabolism and hormonal changes, older women aged between 40 and 60 fall into the healthy range between 23% and 35% body fat. 25% is a good average to aim for. More than 32% body fat increases the risk of obesity related illness.

Higher body fat percentages usually result from too little activity, too much food, or a combination of the two. The longer these conditions continue, the higher the percentage of body fat is likely to rise. While genetics may play a fact in fat storage - if your mother had big hips, you're more disposed to the same problem - increase in body fat is almost always related to lifestyle.

Stored body fat uses around 2 calories per pound per day, while lean muscle uses up to 6 calories per pound for day. This doesn't sound much, but over one year, 10lbs of muscle will burn 14,600 more calories in one year than 10lbs of fat, which equates to a 4lb weight loss without doing anything at all. * 

With proper exercise and optimum nutrition, your body fat percentage will decrease as you build up lean muscle. Even if your weight doesn't appear to be reducing, your clothes will fit better, as muscle takes up much less space than stored body fat. For in depth advice on how to reduce your body fat percentage safely and permanently, visit Ask the Trainer.

Source: http://askthetrainer.com/body-fat-percentage-in-wome n.html.

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