A body fat scale is similar to a regular bathroom scale in that you step on it and it provides a digital reading. However, in addition to your weight in pounds, a body fat scale also claims to provide your body fat percentage. This can be an interesting number to track, especially for those on a weight loss regime that includes exercising. It can be frustrating when the number on the scale will not budge while you are dedicated to your exercise and healthy eating plan.

This is where a body fat scale may play a useful role. It is possible that your body composition may be changing while your body weight remains the same. This occurs when you are losing body fat and gaining muscle (a good thing!). Muscle weighs more than fat. So, you actually may be making great progress and a body fat scale will reflect this more accurately than a typical scale.

How do they work? Body fat scales use Bioelectrical Impedance Analysis (BIA). A very small, harmless electrical current passes through your body tissues, slower through fat and quicker through muscle. Resistance is what is being measured. So, actually it is not analyzing your body fat percentage so much as your body density. The scale then takes this reading and uses a formula to give you a body fat percentage reading.

Are they accurate? No. They give an estimate and studies have concluded that body fat scales do not give precise readings. Consumer Reports tested body fat scales and found them all to be inaccurate. Factors such as body type, body temperature, hydration, and recent exercise can have a noteworthy impact on the number you see on the scale. Even wet or sweaty feet can skew the results. Whether or not you get a true analysis, what you can do is use that number to gauge your progress. But you must be consistent when you weigh yourself, so do it at the same time of day, drink/eat approximately the same amount, don't do it directly after exercising, and use it in a room that is generally a stable temperature. Utilize the body fat scale as a means of tracking trends rather than focusing on what that number is or comparing that number to what you think your body fat should be.

What do they cost? You can get one for under $100. Look for features such as multiple-user memory where you can store data for several users. The Tanita Body Fat/Body Water Monitor earned four out of five stars on Amazon and sells for about $60. The Omron Body Fat Monitor and Scale also got great reviews and sells for about $40.

Body fat scales can be a useful device for monitoring your weight loss. They may not always be exact so try not to get too obsessive with the numbers they display. Use a body fat scale to help stay motivated, but the best way to know how you are doing is awareness of how your clothes fit and how your body feels.

Corinne Goff is a Registered Dietitian who is absolutely passionate about food, health, and nutrition. Corinne has a BA in Psychology from Salve Regina University and a BS in Nutrition from the University of Rhode Island. As a nutritionist, her objective is to help people reach their health goals by offering a personalized holistic approach to wellness that incorporates natural foods and lifestyle changes. She works together with her clients to develop daily improvements that they feel comfortable with and that are realistic. She believes that the focus on wholesome, nutrient-rich, real food, is the greatest possible way to become healthier, have more energy, decrease chances of chronic disease, and feel your best.