What Is Body-Fat Percentage?

by JJ Virgin on March 23, 2023

When you hear “body fat,” you might think about losing weight for summer or struggling to get into your favorite skinny jeans. But body fat is about more than just aesthetic—it’s an important component of body composition.  

Your body composition refers to the amount of fat you have compared to lean tissue. (Lean tissue is the weight of your muscles, bones, body water, and organs.)  

Put another way, your body-fat percentage is your total mass of body fat, divided by total body mass, multiplied by 100.  

Here’s an example: If you weigh 150 pounds and have 20% fat, that means that your body consists of: 

  • 30 lbs fat  
  • 120 lbs lean body mass 

Total mass of body fat (0.20), divided by total body mass (150), multiplied by 100 = 30 lbs fat. 

What Is Body Fat? 

Body fat falls into two categories:  

  • Essential body fat, or the amount of fat you need to live. Women carry more essential fat than men do. 
  • Storage body fat, or the amount of fat that you store in fat tissue (including fat that protects your internal organs). 

A certain amount of body fat is critical for many functions throughout the body, including: 

  • Energy. Your body can use stored fat when food is scarce or when you're physically working hard. 
  • Temperature regulation. Body fat can regulate body temperature and keep you warm. 
  • Protection. Fat cushions your internal organs, including your heart and kidneys. 
  • Hormones. Fat cells produce hormones that help regulate your metabolism, appetite, and insulin sensitivity. 
  • Nutrients. Vitamins A, D, E, and K are fat-soluble. Fat tissue absorbs and stores these nutrients until your body needs them. 

Too much fat can create problems. Studies show that a high body-fat percentage can contribute to metabolic syndrome, a cluster of symptoms that includes high blood pressure, high triglycerides, and obesity.1 

The most harmful type of fat is abdominal or visceral fat. This dangerous fat is stored deep inside your body, around your stomach, liver, intestines, and other organs. Even if your weight is within normal range, studies show that too much visceral fat can create serious health repercussions.2 

Research shows that reducing your weight—and more specifically, body fat—by 5-10% substantially lowers all aspects of metabolic syndrome as well as your risk of type 2 diabetes and cardiovascular disease.3 Other research associates high body fat with an increased risk of osteoporosis, lower joint and functional strength, and an increased risk of early death.4, 5, 6 

How to Find Your Ideal Body-Fat Percentage 

While a bathroom scale can tell you how much you weigh, a body-composition scale tells you whether you’re building muscle or putting on body fat. In other words, just because you aren’t losing weight doesn’t mean you aren’t losing fat. You could be gaining muscle and losing fat at the same time, which may not impact the scale as much as you’d like. But how do you know how much of your body is fat and how much is lean mass?  

One study looked at 4,735 adults and found that the body-fat cut-offs were 25.8% for men and 37.1% for women. Above those numbers, your risk of developing cardiovascular risk factors is two to four times higher than when you keep your body fat below these levels.7 

More specifically, ideal body-fat ranges for men and women fall into the following percentages based on a Built Lean® chart:  


  • Average body-fat range: 25-31% of your total weight 
  • Optimal/fitness range: 21-24% 
  • Younger or very athletic woman: 14-20% 


  • Average body-fat range: 18-24% of your total weight 
  • Optimal/fitness range: 14-17% 
  • Younger or very athletic man: 6-13% 

Of course, you want to be optimal and not average! If you’re above those averages, you’re considered metabolically unhealthy. As a result, your blood-sugar levels tend to fluctuate, leading to hunger and cravings. You’re also more likely to have chronic inflammation, which paves the way for nearly every disease. 

The great news is that even if you currently have an unhealthy body-fat percentage, you can change that. The first step is measuring your body fat—because what you measure, you can improve.  

5 Ways to Measure Body-Fat Percentage 

Knowing how much body weight you have is the best way to find out whether you fall within healthy ranges (and take the right strategies if you don’t). There are five main body-composition analysis tests. As you’ll see, some are more accurate than others. 

  1. Skinfold test. Skinfold calipers pinch your body and measure body fat. The test is unpleasant and usually inaccurate. It only measures subcutaneous fat and totally misses visceral fat (the most dangerous kind).   
  1. Hydrostatic weighing (also called underwater weighing). You’re weighed while both submerged underwater and while on dry land, after exhaling as much air as possible from your lungs. Researchers measure the amount of air left in your lungs after you exhale. From these measurements, they use your body’s density to predict your body-fat percentage. With a margin of error of around 1-3%, hydrostatic weighing is fairly accurate. 
  1. BOD POD®. This air-displacement method is similar to hydrostatic weighing (and is just as accurate), but it uses air instead of water. The relationship between the volume and pressure of air allows this device to predict your body density. The BOD POD also tells you how many calories you burn at rest, which can be useful when you’re monitoring your overall caloric intake.   
  1. Dual-Energy X-Ray Absorptiometry (DXA). A DXA or DEXA scan is the most accurate and advanced body-composition analysis you can do. You probably know it as a bone-density scan, but it can also differentiate between subcutaneous and visceral fat. Plus, it provides a detailed assessment of how much muscle mass and fat mass you have, down to the pound. You only need to do this once or twice a year.   
  1. Bioelectrical Impedance Analysis (BIA). Bioelectrical Impedance Analysis (BIA)—aka a body-composition scale—is the most accessible and affordable option. It uses a low electric current that travels through your body to estimate your fat-free mass. The margin of error for body composition analysis is about 3-8% which is good for something that gives you so much control.  

A body-composition scale is my favorite way to measure and track your body composition. You can monitor your lean mass and body fat consistently. Ideally, get one that also tells your visceral fat. These scales are portable, affordable, and easy to find. Two favorites are this Tanita® scale and this Omron body-composition scale

Here’s how to use them: 

  1. Determine your ideal body weight. This is based on your height and frame size (this calculator is simple and helpful). Multiply that number by your ideal lean body mass percentage (100 minus your ideal body-fat percentage). Let’s say your goal is 20% body fat. Multiply your ideal body weight by .8 and that should be your lean body mass.   
  1. Pay attention to body fat and especially visceral fat (VAT). Keep this dangerous type of fat to 10% of your total fat or less. If you weigh 150 pounds and you have 20% body fat or 30 pounds of fat, you should have no more than three pounds of visceral fat.  
  1. Make the scale your friend! Tracking your numbers can help you determine what you’re doing correctly and what you should consider tweaking. 

Knowing your composition is the first step in transforming your body and understanding your progress. If you’re just getting started working on your weight or fitness, a body-composition scale provides a benchmark and puts you way ahead of the curve. 

I want you to weigh in daily. However, you don’t have to monitor body fat daily. Instead, watch the trends over time. Check in at least once a week to see if your body-fat percentage or muscle mass is changing (and if so, how). If the number seems off, then take the trend over a couple of days.   

As you do this, fine-tune your nutrition and fitness habits based on your results. Here are two ways to do that. 

Eat by the Plate to Improve Body-Fat Percentage 

If you want to lose fat and improve your body composition, change what’s on the end of your fork.  I take a protein-first approach to eating. Eating the right amount of protein—at the right times—is the best way to gain muscle and lose weight.   

Studies show that eating higher amounts of protein when you’re trying to lose weight improves body composition by helping retain lean mass and reduce fat mass.8 Make protein the first thing you put on your plate to build muscle and maximize fat loss. To do that, make every loaded smoothie and meal balanced with protein, fat, and fiber.  

You also want to make sure you are utilizing that great protein. If you’re over the age of 35 or under stress, a digestive-enzyme supplement ensures that you’re breaking down protein and other micronutrients efficiently. Protein First Enzymes contains a proprietary blend of digestive enzymes along with betaine HCl to support optimal digestion and absorption.*  

Healthy fats are critical, too, for supporting lean body mass and reducing body fat. Research shows that the medium-chain triglycerides (MCTs) in coconut oil and coconut milk can improve body composition.9 Likewise, the omega-3 fatty acids in foods like wild-caught fish can reduce the inflammation that makes your body hold on to fat.10 

Fiber can positively impact body composition, too.11 Fiber-rich foods help you stay full longer, cravings stay at bay, and your blood-sugar levels stay nice and steady.  Altogether, protein, healthy fats, and fiber support optimal body-fat percentages so you achieve and maintain your healthy weight. 

Build Muscle to Improve Body-Fat Percentage 

Building muscle also improves your body composition. While moving more can help you burn calories and lose body fat, building muscle is a surefire ticket to getting better results. 

Building muscle can help improve your ideal body-fat percentage in a few ways: 

  1. Muscle tissue is denser than fat tissue. When you build muscle, you may see an increase in weight on the scale. That increase comes from muscle mass. I can’t say this enough: that’s why you want a body-composition scale that provides lean mass and body fat. 
  1. Building muscle can increase your metabolism, so your body burns more calories at rest.  
  1. Building muscle mass improves your muscle-to-fat ratio, which can reduce your body-fat percentage. 

To build muscle, you need the right exercise plan, which includes strength or resistance training. Lifting weights is a great way to support your lean mass and help you burn fat. So are bodyweight exercises, which challenge your muscles and build strength. 

Creating Lasting Change 

As you work to improve your ideal body fat with these strategies, the most important thing I’ve found is to stay consistent. That’s how real change happens.   

That doesn't mean you need to suffer. Make small changes that you can handle, build on them consistently, and be patient. Pick a small goal like getting more protein and keep working on that one thing until you nail it. Then, take another look at your goals and fine-tune them or add new ones as you go.   

I’ve compiled some resources to help you along the way: 

*These statements have not been evaluated by the Food & Drug Administration. Products mentioned are not intended to diagnose, treat, cure, or prevent any disease. The views in this blog by JJ Virgin should never be used as a substitute for professional medical advice. Please work with a healthcare practitioner concerning any medical problem or concern. 


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  1. Harvard Health Publishing: Can body fat percentage determine whether you are overweight? 
  1. Han TS, Lean ME. A clinical perspective of obesity, metabolic syndrome and cardiovascular disease. JRSM Cardiovasc Dis. 2016 Feb 25;5:2048004016633371. doi: 10.1177/2048004016633371. PMID: 26998259; PMCID: PMC4780070. 
  1. Tomlinson DJ, Erskine RM, Morse CI, Onambélé GL. Body Fat Percentage, Body Mass Index, Fat Mass Index and the Ageing Bone: Their Singular and Combined Roles Linked to Physical Activity and Diet. Nutrients. 2019 Jan 18;11(1):195. doi: 10.3390/nu11010195. PMID: 30669348; PMCID: PMC6356293. 
  1. Bulbrook BD, La Delfa NJ, McDonald AC, Liang C, Callaghan JP, Dickerson CR. Higher body mass index and body fat percentage correlate to lower joint and functional strength in working age adults. Appl Ergon. 2021 Sep;95:103453. doi: 10.1016/j.apergo.2021.103453. Epub 2021 May 8. PMID: 33975206. 
  1. Padwal R, Leslie WD, Lix LM, Majumdar SR. Relationship Among Body Fat Percentage, Body Mass Index, and All-Cause Mortality: A Cohort Study. Ann Intern Med. 2016 Apr 19;164(8):532-41. doi: 10.7326/M15-1181. Epub 2016 Mar 8. PMID: 26954388. 
  1. Macek P, Biskup M, Terek-Derszniak M, Stachura M, Krol H, Gozdz S, Zak M. Optimal Body Fat Percentage Cut-Off Values in Predicting the Obesity-Related Cardiovascular Risk Factors: A Cross-Sectional Cohort Study. Diabetes Metab Syndr Obes. 2020 May 12;13:1587-1597. doi: 10.2147/DMSO.S248444. PMID: 32494175; PMCID: PMC7229792. 
  1. Kim JE, O'Connor LE, Sands LP, Slebodnik MB, Campbell WW. Effects of dietary protein intake on body composition changes after weight loss in older adults: a systematic review and meta-analysis. Nutr Rev. 2016 Mar;74(3):210-24. doi: 10.1093/nutrit/nuv065. Epub 2016 Feb 16. PMID: 26883880; PMCID: PMC4892287. 
  1. Mumme K, Stonehouse W. Effects of medium-chain triglycerides on weight loss and body composition: a meta-analysis of randomized controlled trials. J Acad Nutr Diet. 2015 Feb;115(2):249-263. doi: 10.1016/j.jand.2014.10.022. PMID: 25636220. 
  1. Albracht-Schulte K, Kalupahana NS, Ramalingam L, Wang S, Rahman SM, Robert-McComb J, Moustaid-Moussa N. Omega-3 fatty acids in obesity and metabolic syndrome: a mechanistic update. J Nutr Biochem. 2018 Aug;58:1-16. doi: 10.1016/j.jnutbio.2018.02.012. Epub 2018 Feb 27. PMID: 29621669; PMCID: PMC7561009. 
  1. Gibson R, Eriksen R, Chambers E, Gao H, Aresu M, Heard A, Chan Q, Elliott P, Frost G. Intakes and Food Sources of Dietary Fibre and Their Associations with Measures of Body Composition and Inflammation in UK Adults: Cross-Sectional Analysis of the Airwave Health Monitoring Study. Nutrients. 2019 Aug 8;11(8):1839. doi: 10.3390/nu11081839. PMID: 31398891; PMCID: PMC6722677.