How Do Scales Measure Body Fat

How body fat scales work

To one degree or the other, we are all concerned about how we look. This body image rides a lot on how overweight or underweight we think we are.

Fitness- Fitfam- is the constant trend these days, and people see body fat as an anathema.

How exactly do body fat scales work? They work with the help of the underfoot sensors that use bioelectrical impedance. When you get on the device, a tiny electrical current travels up one of your legs and across your pelvis to measure the resistance it encounters from body fat along the way. The sensors register this resistance level the current encountered even as it travels back down through your other leg to complete its circuit.

Generally, greater body resistance indicates a higher body fat percentage because fat is denser than muscle and makes it more difficult for a current to run through.

This BIA method calculates an estimate of your total body water because fat has less water than muscles. Therefore, total body water calculation is used to estimate how fat-free your body mass is. The technology pinpoints your fat mass by comparing your body water level to your body weight.

Some body fat scales have built-in technology which relays this information to your Smartphone, smartwatch or some other fitness app you have. You get your reading immediately in living HD colour.

Types of Body Fat Scales

Body fat scales are high tech scales. High tech scales are just one type of scales. Before high tech scales, there were basic analogue and digital scales.

Analogue scales are also known as mechanical scales. They are those scales that offer foot platforms and legible dials, which operate by a spring mechanism without any need for batteries.

Digital Scales are similar to analogue scales in their simplicity.  They are battery-operated. Some models come with memory-reading functions that memorise up to 10 previous readings.

High-tech scales go beyond both the analogue and digital scales to probe body composition in more details. As I said, body fat scales belong in this category. They use the Body Impedance Analysis (BIA) method to distinguish between fat and muscle mass. Some of these models sync to your Smartphone using Wi-Fi or Bluetooth by which they instantly update you with your Body-Mass-Index (BMI) charts and digital weight.

There are also high tech models that favour the visually impaired.

Generally, any other type of scale falls under one of the above categories.

The pros and cons of body fat scales

One obvious benefit of the body fat scales is that it allows you to measure your body fat right in the comfort of your home. You do not have to make the arduous trip to the gym or clinic.

These scales cannot be your sole method to measure body fat because they leave you with more questions than answers. A body fat device will tell you your overall body fat percentage. However, it won't specify the areas on your body where you have this dangerous fat. Therefore, they do not solve your problem.

Doctors tell us that fat stored around the midsection increases the risks of heart diseases. If the scale cannot pinpoint the problem spot, what good does it do you? What does knowing your body fat percentage help you achieve if you are trying to shed fat?

The BIA technology is quick and impressive and, perhaps, this is why accuracy is compromised. If you were to hop on a body fat scale right after a meal, your result would be sharply inaccurate. Your water level would have risen, and the device will erroneously give you a low fat-mass reading.


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How can I lose body fat quickly?

Start Resistance Training: Lifting weights help you develop fitness and burn fat quickly.

Change your drinks: This contributes immensely to weight loss.

A protein-rich diet goes a long way: This will cut down appetite and build muscle mass.

Get a little more sleep: This militates against weight gain.

Do Cardio:  Cardio reduces the circumference of the waist.

Drink Coffee: Caffeine is a fat-burning ingredient

Add probiotics to your diet: Try adding some probiotic-rich foods like kombucha, kimchi, kefir and sauerkrauts to your menus.

About the Author Harry Thompson

Gaining a BSc Honours in building/ property maintenance at the University of Portsmouth Harry went into the field of renovating properties. Along the journey, he has developed a wide variety of home & garden DIY skills such as installing new kitchens and landscaping gardens.