Body Fat Analyzers & Weight Scales

Recent estimates indicate that 34 million adults are considered obese (20 percent above desirable weight). Also, there has been an increase in body fat levels in children and youth over the past 20 years. After infancy and early childhood, the earlier the onset of obesity, the greater the likelihood of remaining obese. It is important to monitor your body fat level for good health. Excess body fat places greater physical demands on the body, impairs movement and can contribute to several poor health conditions. Excess body fat has been linked to such health problems as coronary heart disease, high blood pressure, osteoporosis, diabetes, arthritis and certain forms of cancer. Obesity may increase your risk of developing high blood pressure, high blood cholesterol and diabetes.

Your level of body fat is one indicator of your fitness level and a predictor of your correct body weight. Height and weight charts are poor indicators of your correct body weight and should not be used to determine your correct weight. Unfortunately, these charts do not consider the uniqueness of each individual and their variations in bone size and body composition. Body fat can not be determined from an ordinary bathroom scale and you can not tell a person's body fat level from appearance as we store fat differently in the body and around internal organs.

Types of Measurement Devices:

a. Handheld Bioelectric Impedance Analysis Device
b. Skinfold Calipers
c. Bioelectric Impedance Analysis Scale

The two most common methods used for measuring body fat and body composition in the home are:

Skinfold Calipers: -

These are instruments that measure the thickness of a subcutaneous (under skin) fat layer at different locations on the body. An assistant will locate and measure various points on your body, most commonly the upper arm, upper back and waist, by pinching folds of skin and fat tissue and measuring their thickness with a caliper. These measurements are then used in a scientifically proven mathematical formula, which incorporates other individual factors such as weight, age and gender, to calculate your total body fat level. Several factors will influence the accuracy of the results and repeated accuracy over subsequent tests such as pressure on the caliper head, correct skin fold pinching technique and duplicating the exact measurement locations.

Bioelectrical Impedance Analysis (BIA): -

This technology is considered one of the most accurate and easily accessible methods of determining body fat levels. Bioelectrical Impedance is able to recognize fat at both the surface of the body and between internal organs where body fat is unseen. An unfelt, safe, extremely low energy, high frequency electrical signal is sent from one contact point on the body to another body contact point and a measurement of baseline impedance to the flow of the signal is made as it traveled through the body. Using knowledge of the conductivity of fat tissue and water, these devices calculate the speed at which the electrical signal travels through your body's tissues and the analyzer will use this electrical resistance information to calculate body fat weight and body fat percentage in consideration of age, height, weight and gender.

Body Composition Measurements:

Advances in medical testing technology and data analysis have allowed home body composition measurement equipment to provide feedback, analysis and estimate values for a variety of health related body factors:

Weight: - using your weight measurement alone is not an accurate indicator of proper weight and body composition. A weight measurement by itself can not differentiate between body fat and fat free mass in the body.

Body Fat: - located under the skin (subcutaneous), between the muscles (intramuscular) and around internal organs (visceral), this tissue serves to provide insulation against heat/cold, protective padding, energy and nutrient stores and proper functioning of hormonal and immune systems. Excess body fat is a risk factor for cardiovascular disease and can contribute to health conditions such as Diabetes, high blood pressure, sleep apnea and Osteoarthritis.

Body Mass Index (BMI): - this is a simple calculation to determine a person's height to weight ratio. This method provides a slightly more accurate representation of the body composition than weighing alone, but is not considered a good body composition indicator by health and medical professionals because it doesn't take into consideration muscle mass and other genetic factors. For example, two people can have an elevated BMI reading and one can have normal levels of body fat and the other individual can have undesirable elevated levels of body fat.

Visceral Fat: - these are the deep underlying fat stores located around the internal organs of the abdomen. Researchers at Johns Hopkins Medical Institutions found Visceral Fat to be likely to increase heart attack risk and may be a greater predictor of heart disease and diabetes than simple weight or body mass index (BMI). While paying attention to waist size is important, it is very difficult to measure the amount of visceral fat a person has with just a measuring tape and regular scale.

Resting Metabolism: - the minimum amount of energy the body consumes while at complete rest and is needed to sustain the body's functions. Resting metabolism is impacted by the amount of lean body mass and exercise. About 60% to 70% of daily energy use is for resting metabolism.

Skeletal Muscle: - this is the muscle attached to the bones of the body to create movement. Skeletal muscle mass can be increased with exercise which may be desirable in changing the body composition and reducing body fat levels.

Weight Loss and Body Fat Considerations:

Overweight and overfat do not always mean the same thing. Some people are quite muscular and weigh more than the average for their age and height and would have a high Body Mass Index. However, their body composition, the amount of fat versus lean body mass (muscle, bone, organs and tissue), is within a desirable range. Others weigh an average amount and have a good Body Mass Index yet carry around too much unhealthy fat. Weight alone is not a good indicator of your body composition and it is important to evaluate your body fat and lean muscle mass to determine if they are at optimum healthy levels.

Another important reason to monitor your body fat level is when on a weight reduction program. In simple terms, if you expend more energy (calories) than you consume, a weight loss will result and the opposite is true for weight gain. How the weight is reduced and the corresponding change in body composition is important. A weight reduction program goal should be to attain healthy levels of body fat and not be based on the weight value alone as many popular diets are. Proper exercise and good dieting habits are critical to effective healthy dieting and weight loss.

A B
Initial Body Fat Level 36.0% 36.0%
Total Weight Loss 20 lbs. 20 lbs.
Fat Reduction 6 lbs. 18 lbs.
Lean Body Mass Reduction 14 lbs. 2 lbs.
End-of-Diet Body Fat level 36.9% 28.3%

Weight Loss Dieting :-

Where dieting results in rapid weight loss or with poor nutritional guidelines, a reduction in lean body mass, rather than body fat, may result. Rapid weight loss and starvation diets force the body into a state where it utilizes it's lean body mass for energy requirements. Additionally, repeated dieting and regaining weight leads to increased visceral (internal) fat levels rather than increased subcutaneous (below skin) fat levels. In the example above, "A" and "B" are both the same height, weight and have the same body fat levels when they started to diet. Both A and B lost 20 pounds of weight. A's body fat level actually increased slightly, while B's fat level was reduced (combined exercise and dieting). Exercising to increase lean body mass creates a higher resting metabolism to burn more calories and improve body composition. As a result, A actually has a higher body fat percentage then when a weight loss program was started and although there was a weight loss, there was not a reduction in corresponding health risk factors.

Without monitoring your body fat level to indicate if your fat level is decreasing during your weight reduction program, you may be reducing lean body weight, such as muscle tissue, and not reducing body fat levels. Therefore, it is possible to lose weight on a weight reduction program and have the same or more body fat as before you started the weight loss program! This is a real problem with many weight reduction programs that don't follow sensible nutritional and exercise guidelines.

Accuracy and Safety of Bioelectric Impedance Analysis :

Not all Bioelectrical Impedance Analysis (BIA) body fat analyzers are the same! There are many companies producing weight scales and inexpensive handheld devices providing body fat readings through Bioelectric Impedance Analysis. Omron is a leader in this technology and have done extensive University based research and human testing to develop accurate equations and algorithms used in estimating body fat from BIA technology. The accuracy of Omron BIA analyzers have been highly correlated against clinically accurate body fat analysis methods such as hydrodensitometry (under water weighing), Dual Energy X-ray Absorptiometry (DXA) and Magnetic Resonance Imaging (MRI).

Safety Precaution: Bioelectric Impedance Analysis devices pass an extremely weak electrical signal through the body when taking a measurement. This electrical signal is not felt and is safe for individuals without cardiac pacemakers and implanted medical devices. As a precaution, persons with cardiac pacemakers, electrocardiographs and/or other medical devices implanted in the body or used for life support, should not use Bioelectric Impedance Devices.