Understanding Body Fat Percentage

You think you’ve left math behind in school, then, BAM! You start to hear about body fat percentage. What does that even mean? Luckily, understanding body fat percentage is much easier than high school math. 

Body fat percentage is a measure of how much body fat you have relative to your overall body weight. It can be an accurate way of assessing whether you are underweight, a healthy weight, overweight or have obesity. 

Below, we share everything you need to know about body fat percentage, including how it’s calculated, what a healthy body fat percentage is and what impacts body fat percentage.

As we said, body fat percentage is the amount of body fat you have in relation to your overall body weight.

It can help determine whether you are at a healthy weight more accurately than measures like body mass index (BMI).

This is important, as being overweight or having obesity can put you at higher risk of health conditions like: 

• High blood pressure

• Type 2 diabetes 

• Stroke 

• Heart disease 

• Some cancers 

Measuring your body fat percentage is one component of measuring your overall body composition, which calculates fat, muscle and bone percentages. A healthcare provider can use these percentages to diagnose conditions like visceral obesity (obesity around the center of the body). 

Knowing your body composition is also helpful in evaluating the effectiveness of nutritional interventions, monitoring changes linked with aging and assessing health conditions like diabetes, cardiovascular diseases, cancer, osteoporosis and osteoarthritis.

Similar to body fat percentage, BMI is a way to determine whether someone is underweight, a healthy weight, overweight or has obesity. BMI indicates how much body fat you have but does not directly calculate body fat percentage. 

BMI is calculated by dividing a person’s weight in kilograms by their height in meters squared. 

In imperial speak, that’s your weight in pounds divided by your height in inches squared, multiplied by 703. 

BMI = lbs/in² x 703 

Not in a math mood? Check out the Hers BMI Calculator.

Simple enough, right? But there are a few problems with BMI that may make body fat percentage a better health metric. 

If you have a lot of muscle mass — think bodybuilders or athletes — your BMI may be high, but you may have low body fat. BMI can also underestimate body fat in older people or those who have lost muscle. 

This can make it inaccurate when determining whether someone has obesity or is overweight.

A 2012 study of 490 participants showed this in action. It found that when measured using BMI, 14.3 percent of the men and 7.8 percent of the women had obesity. 

However, when they measured body fat percentage, those numbers changed — in that case, 8.9 percent of men and 22.8 percent of women had obesity. 

Quite the difference, right?

The study concluded that body fat percentage was a better measure of whether someone is at a healthy weight or has obesity because it’s better than BMI at telling the difference between lean muscle mass and fat mass. 

You can check out our guide to BMI to learn more.

Unfortunately, there isn’t a simple online body fat calculator. In most cases, you’ll have to visit a healthcare provider to measure body fat percentage accurately. 

Body fat percentage can be calculated in many different ways, including: 

• Anthropometry. Anthropometric measures include waist circumference, waist-to-hip ratio and skinfold measurements (using calipers to measure subcutaneous fat in places like your biceps and triceps). They are used to estimate bone density and derive body fat percentage. 

Anthropometry is often used in clinical settings since these measures are inexpensive and relatively simple. However, they aren’t always accurate for older folks and those with obesity. 

• Dual-energy X-ray absorptiometry (DEXA) scans. During a DEXA scan, you’ll lay on a bed as an X-ray beam passes over your body, just like an X-ray you may get for a broken leg. 

Fat, muscle and bone have different densities and chemical compositions, so they absorb X-rays differently. DEXA scans use two different X-ray energies to build an image of your body composition and determine body fat percentage.  

• Bioelectrical impedance analysis (BIA). This analysis measures electrical conduction in your body to determine how much fat and lean tissue you have. 

Lean tissue, like muscle, contains water, so it’s a good electrical conductor. Fat, on the other hand, doesn’t contain water, so it’s a poor conductor. Measuring electrical conduction can help your provider determine how much of each you have.

• Air displacement plethysmography (ADP). With ADP, you sit inside a chamber known as a Bod Pod for about five to eight minutes. This chamber measures your body volume by comparing the air volume when you’re inside the chamber to the air volume before you get in. This is used to determine bone density and, therefore, body fat and lean mass. 

There’s no one agreed-upon healthy body fat percentage — that number will look different for everyone. 

Generally, a body fat percentage of 35 or more in women is considered a sign of obesity. For men, it’s 25 percent or more.

Ideal body fat percentages can vary, though. 

A 2020 study looked at more than 4,700 people whose body fat percentage was measured using BIA. They found that people with higher body fat percentages than the following cut-offs had two to four times higher odds of developing cardiovascular risk factors than those with body fat percentages under these cut-offs:

• 37.1 percent body fat for women 

• 25.8 percent body fat for men 

What Does 15 Percent Body Fat Look Like? 

Body fat percentage is highly individual. So, 15 percent body fat — or 10, 20 or 30 percent body fat, for that matter — will look and feel different from person to person. 

At lower body fat percentages, like 10 percent to 20 percent, you may look lean and show some muscle definition. At body fat percentages around 20 to 30, you’ll notice a little more fat. 

The amount of fat you have, and therefore your body fat percentage, can be influenced by factors like: 

• Lifestyle habits, including food choices and how much movement and sleep you get 

• Medications, like drugs for high blood pressure, diabetes and depression 

• Health conditions like polycystic ovary syndrome (PCOS), hypothyroidism and depression 

• Family history and genes — thanks, Mom

Looking at recommendations for healthy body fat percentages is a good place to start when figuring out what your body fat percentage should be. 

However, ideal body fat percentage ranges can vary by several factors, including age. More importantly, everybody is unique, so it’s best to speak with a healthcare provider to determine what body fat percentage is healthy for you. 

How Do I Get My Body Fat Percentage Down?

You can’t really do much about some factors that influence body fat percentage, like genetics. However, it is possible to get your body fat percentage down by losing fat. If that’s your goal, you can consider: 

• Switching up your eating habits. Try eating more protein, opting for fruits and veggies and stocking your cupboard with healthy snacks.

• Getting more movement. This doesn’t have to be a hardcore HIIT session. Even walking a little more each day can help with weight management. Check out our guide to how many steps a day you need to lose weight to get started. 

• Getting enough shut-eye. Sleep can help with weight loss, as research shows that a short sleep duration is linked with obesity. 

• Weight loss drugs. Weight loss injections and oral weight loss medications could play a part in your weight loss journey. Talk to a healthcare provider to determine if these are right for you.

If you’re curious about your body fat percentage or want to learn whether weight loss should be your goal, speaking to your healthcare provider is your best bet. 

Here’s what to ask: 

• What is a healthy body fat percentage for me? 

• What is the normal body fat percentage for women?

• How can I get to a healthy body fat percentage for me? 

• Are there weight loss medications I should consider?  

• Should I get a body fat percentage test?

Body fat percentage is one way to determine if you have a healthy weight. For some, it may be a more accurate measure than BMI. 

Here’s what you need to know: 

• A healthcare provider can let you know what’s healthy for you. Generally, 35 percent body fat could be a sign of obesity in women. Having about 37 percent body fat or more ups your odds of developing cardiovascular risk factors. 

• There are a few ways of measuring body fat percentage. That includes skinfold calipers and more technical tests like a DEXA scan and BIA test. 

• Body fat percentage is just one health metric. Knowing your body fat percentage can be helpful, but you don’t necessarily need to know it to start a weight loss journey. A healthcare provider may use other methods to determine whether it would be beneficial for you to lose weight. 

If you’re exploring ways to lower your body fat percentage into a healthy range, focus on eating nutritious foods, getting more movement into your day and getting enough sleep each night. There are also plenty of weight loss treatments and other supports to help you on your journey.