Basics Print Body Composition and Body Fat Percentage Definition, Guidelines, and Measurement Methods Medically reviewed by facebook linkedin Medically reviewed by Richard N. Fogoros, MD on June 16, 2016 Richard N. Fogoros, MD, is a retired professor of medicine and board-certified internal medicine physician and cardiologist. He is Verywell's Senior Medical Advisor. Learn about our Medical Review Board Richard N. Fogoros, MD Written by Written by Jennifer R. Scott Jennifer R. Scott is a weight loss writer. She designed her own successful weight loss plan, which helped her safely lose 50 pounds in about a year. Learn about our editorial policy Jennifer R. Scott Updated on August 04, 2019 nadisja / Getty Images More in Weight Loss Basics Procedures Nutrition for Weight Loss Exercise for Weight Loss Diet Plans Medications Supplements Body composition is the proportion of fat and non-fat mass in your body. A healthy body composition is one that includes a lower percentage of body fat and a higher percentage of non-fat mass, which includes muscle, bones, and organs. Knowing your body composition can help you assess your health and fitness level. Often, you will measure your body composition at the start of a weight-loss or fitness program and then check it periodically to monitor your progress. What Is Body Composition? Your body is composed of two types of mass: Body fat and non-fat mass. Body fat can be found in muscle tissue, under the skin (subcutaneous fat), or around organs (visceral fat). Some fat is necessary for overall health. This "essential fat" helps protect internal organs, stores fuel for energy, and regulates important body hormones. But you may also have excess storage of fat and non-essential body fat.Non-fat mass includes bone, water, muscle, organs, and tissues. It may also be called lean tissue. These tissues are metabolically active, meaning they burn calories for energy, while body fat is not. Body fat percent is a measurement of body composition telling how much of the weight of your body is fat. The percentage of your body that is not fat is fat-free mass. There are normal ranges for body fat, which differ for men and women. Weighing yourself on a regular bathroom scale does not assess your body composition. A regular scale cannot tell how much of your total weight is comprised of water, fat, or muscle. To know whether your body composition is healthy, you should get an estimate of your body fat percentage. You can do so by taking simple measurements and entering them into a body fat percentage calculator. Healthy Body Composition The American Council on Exercise (ACE) gives the following ranges of values for different populations. ACE Body Fat Percent Norms for Men and Women Description Women Men Essential Fat 10% to 13% 2% to 5% Athletes 14% to 20% 6% to 13% Fitness 21% to 24% 14% to 17% Acceptable 25% to 31% 18% to 24% Obese Over 32% Over 25% Athletes tend to have lower body fat, which may be beneficial for performance in sports such as running and cycling. But having an extremely low body fat percent is a health problem. For example, the female athlete triad increases the risk of injury and health issues. It includes eating disorders, amenorrhea, and decreased bone mass with an increased risk of stress fractures and osteoporosis. If you are overweight or obese, you have an excessive amount of body fat and a high body fat percentage. If your body fat percentage is too high, you can improve your body composition by gaining lean body mass through building muscle and bones and by losing excess body fat. How to Measure Your Body Composition There are several ways to get an estimate of your body fat percentage at home, at the gym, or from your doctor. Bioelectrical Impedance Bioelectrical impedance can be measured by handheld units and by BIA body fat scales that you step onto like a regular scale. These tools pass a small electrical current through your body. Fat, water, and lean tissue impede the current differently to give the reading. Many scales are sold for home use and no special training is required. Some scales, like the Fitbit Aria 2, even sync with your fitness tracker so that you can see how changes to your daily activity and diet affect your weight. Skinfold Measurements Taking skinfold measurements is a method is often used by fitness trainers or as part of a weight loss program. Calipers take measurements at different parts of your body and then a calculation helps translate them into a body fat percentage. DEXA Scan A DEXA scan, or dual-energy x-ray absorptiometry scan, is performed in a medical setting and can also be used to check for bone density. Hydrostatic Weighing Hydrostatic weighing is a method that requires you to be fully submerged in water. This gold standard for body fat measurement involves being dunked in a water tank. It's harder to find a clinic or gym that offers this service. Factors Affecting Body Composition Your body composition can also be influenced by factors you can't control: Age: People lose muscle mass as they age if they don't maintain it with sufficient weight training. This results in a slower metabolism.Sex: Women have more body fat than men as nature's way of preparing for pregnancy and nursing.Genes: These play a role in whether you are naturally lean or have a tendency to retain fat, including where you store it.Hormones: These can influence water retention and body composition. Should You Change Your Body Composition? If your body fat percentage is too high, you may want to try to decrease it to improve your health, athletic performance, and well-being. You may also be able to lower your risk of disease. If your body fat percent is below the level of essential fat, you may also want to make changes to bring it, as that will reduce your health risks as well. To change your body composition for better health and fitness, aim to increase muscle mass and decrease excess fat mass. You can change your diet, start an exercise program, or combine both methods. A Word From Verywell Your body composition and body fat are important measurements when you are on a weight loss program. You could be successful in losing fat and gaining muscle without seeing your weight go down. Tracking your weight loss and fitness efforts with body composition measurement is a good way to see your progress. It is easier than ever with the wide availability of body fat scales. Was this page helpful? Thanks for your feedback! Looking to lose weight? Our nutrition guide can help you get on the right track. Sign up for our newsletter and get it free! Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial policy to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Lee SY, Gallagher D. Assessment methods in human body composition. Curr Opin Clin Nutr Metab Care. 2008;11(5):566-72. doi:10.1097/MCO.0b013e32830b5f23 St-onge MP, Gallagher D. Body composition changes with aging: the cause or the result of alterations in metabolic rate and macronutrient oxidation?. Nutrition. 2010;26(2):152-5. doi:10.1016/j.nut.2009.07.004 Clark JE. Erratum to: Diet, exercise or diet with exercise: comparing the effectiveness of treatment options for weight-loss and changes in fitness for adults (18-65 years old) who are overfat, or obese; systematic review and meta-analysis. J Diabetes Metab Disord. 2015;14:73. doi:10.1186/s40200-015-0154-1 Additional Reading American Academy of Orthopaedic Surgeons. Female Athlete Triad: Problems Caused by Extreme Exercise and Dieting. http://orthoinfo.aaos.org/topic.cfm?topic=A00342. American Council on Exercise. Tools and Calculators. https://www.acefitness.org/acefit/healthy_living_tools_content.aspx?id=2 Fahey TD. Fit & Well: Core Concepts and Labs in Physical Fitness and Wellness. New York: McGraw-Hill Education; 2017. National Heart, Lung, and Blood Institute. Assessing Your Weight and Health Risk. https://www.nhlbi.nih.gov/health/educational/lose_wt/risk.htm. Continue Reading