Introduction to Body Fat Percentage(BFP)

• The scientific name for body fat is "adipose tissue." Adipose tissue serves a number of important functions. It's primary purpose is to store lipids from which the body creates energy. It also secretes a number of important hormones.
• Having an excess of body fat leads to the condition of obesity, and that can be unhealthy. Some people are more genetically predisposed to excess body fat, and others build it up from lack of exercise and bad diets.
• But body fat stored in the abdominal region can be reduced by diet and exercise. Women and men store body fat differently – after the age of 40, or after menopause in the case of women, reduced sexual hormones can lead to excess body fat around the stomach in men, and around the buttocks and thighs in women.

How to calculate?

Specific techniques must be used to measure body fat. The U.S. Navy has come up with a straightforward and useful method – equations developed by Drs. Hodgdon and Beckett at the Naval Health Research Center take into account differences in the way men and women accumulate fat, thus different measurements are required. Calculation is in centimeters.

• Example info:

height<-180; neck<-50; waist<-90; hip<-90;

• Below is the BFP calculation for Male.

495/(1.0324-0.19077*(log10(waist-neck))+0.15456*(log10(height)))-450

## [1] 10.31527

• Below is the BFP calculation for Female.

495/(1.29579-0.35004*(log10(waist+hip-neck))+0.22100*(log10(height)))-450

## [1] 19.53233

Recommended Intake Based on Type of Activity

According to Health Check Systems, The American Council on Exercise has categorized the range of body fat percentage.

Women:

• Essential fat = 12-15%

• Athletes = 16-20%

• Fitness = 21-24%

• Acceptable = 25-31%

• Obese = 32%+

Men:

• Essential fat = 2-5%

• Athletes = 6-13%

• Fitness = 14-17%

• Acceptable = 18-25%

• Obese = 25%+

For example, a Male fat whose BFP is 10.3 is known as Essential Fat.

What’s Wrong with Excess Body Fat?

• As we’ve said, it’s appropriate to think of fat as an important producer of essential hormones. Our bodies’ functions are controlled by hormones, and so excess or lack of critical ones can seriously affect our health. Scientists have learned that excess body fat, especially abdominal fat, disrupts the normal balance and functioning of these hormones.
• It is known that body fat pumps out immune system chemicals called cytokines that can increase the risk of cardiovascular disease. These biochemicals are thought to make cells less sensitive to insulin, blood pressure, and blood clotting.
• Another reason that abdominal body fat in excess can be so harmful is that it is located near the portal vein, which carries blood from the intestinal area to the liver. Substances released by body fat, including free fatty acids, enter the portal vein and travel to the liver, where they can impede its functioning.
• Abdominal body fat is directly linked with higher total cholesterol and specifically with the so-called “bad” cholesterol that can clog arteries and lead to a heart attack.
• Insulin resistance means that your body’s muscle and liver cells don’t respond adequately to normal levels of insulin. Insulin is responsible for carrying glucose into the body’s cells. When there is insulin resistance, glucose levels in the blood rise, heightening the risk for diabetes.

References

http://www.calculator.net/body-fat-calculator.html. http://www.scientificpsychic.com/fitness/diet.html.