The mere mention of body fat can conjure images of belly fat, love handles, and extra junk in the trunk. Indeed, you will find thousands of articles with exercise tips or diet secrets that promise to lower your body fat percentage and get rid of x amount of body fat in x days.
But what if it is not that simple? What if there is more than one kind of body fat and more to the story than just burning it?
Body fat is something everyone on which everyone has an opinion, with many misunderstandings. Some people reason that it is just a natural part of getting older, and if their BMI is in a good range you do not have much to worry about. Your body does require some body fat to function, but it also requires you to keep your body fat percentage in a certain range for optimal health.
Let us learn what is body fat, how it affects your health, and how to measure your body fat percentage. First, let us discuss BMI, a shorthand for Body Mass Index, and one of the tools used to assess fat and how it relates to health.
What is Body Mass Index/ BMI?
Body Mass Index is a specific calculation obtained by taking a person’s weight in kilograms and dividing it by the square of height in meters. Many online tools exist to quickly calculate this number. Once calculated, the BMI numbers relate to the zone of low (underweight), normal, or high (obese).
In general, higher BMIs can indicate higher levels of body fat and the risks associated with being overweight. People who have obesity are at increased risk for many diseases and health conditions, therefore BMI is an important tool, but again, not the entire picture.
What is body fat?
It seems like an obvious question: what is body fat? You are probably thinking that it is “the fat you can see and point at.” Yes, that is true – but that is only half the picture.
Body fat, more formally called adipose tissue, does not contain just one type of fat cell, nor is it just one type of fat. Body fat is made up of three unique types of fat cells:
What is white fat?
White fat is the predominant form of fat in the body. Composed of a single lipid droplet, and few blood vessels, this fat gets its name from its lighter, white/yellow. By consuming too many calories, especially when coupled with decreased physical activity, white fat levels increase. This is the fat that accumulates in the hips, thighs, buttocks, and abdomen.
What is brown fat?
Brown fat exhibits a darker, brownish appearance. This fat contains several lipid droplets and many iron-containing cells that burn energy. Sometimes, brown fat is known as the “good fat”.
It is predominantly located in the neck and upper back and is associated with a younger, more slender appearance. Certain lifestyle activities such as exercise, adequate sleep, and cold temperatures can work to convert some white fat into brown fat. This creates the subgroup of beige fat. Think, supercharged white fat, now functioning more like brown fat.
Where is body fat stored?
Within the body, fat cells are stored in three different ways:
Each type of fat has unique properties and exists for specific functions. Having a thorough understanding of the different types of fat, and the various cells inside will help you manage your body fat and make effective changes. Let’s dive into the properties and characteristics of the different types of fat in the body.
What is essential fat and where is it stored?
First, essential fat plays a significant role in your overall health and as its name implies, it is essential for survival. That is why a goal of 1 percent of body fat is neither realistic nor healthy.
Essential fat is present in organs, bone marrow, nerve cells, and the brain, and helps you:
- Maintain sufficient energy reserves by acting as a metabolic fuel.
- Conserve body heat by acting as an insulator.
- Protect your internal organs and joints by acting as a soft, fluffy cushion.
- Reproduce; adipose tissue (fat cells) and fertility are heavily linked to each other.
Normal essential fat values register around 3 percent for men and 8 to 12 percent for women, respectively. The higher ranges in women account for female-specific adipose tissue needs due to childbearing and similar reproductive functions.
What is storage fat and where is it stored?
Meanwhile, nonessential or storage fat is adipose tissue that accumulates as energy reserves. Storage fat affects body shape and appearance. Additionally, storage fat can be further divided into two:
- subcutaneous fat
- visceral fat
Although they are both components of storage fat, they are quite different from each other. So different in fact, that these two types of adipose tissue have different gene expressions. This means they are literally different and function independently from each other.
What is subcutaneous fat?
Located just underneath the skin, subcutaneous fat is adipose tissue that you can see, touch, and pinch. Subcutaneous fat is the type of body fat that most people think of when they hear the word “fat” because it is tangible.
While too much subcutaneous fat can pose a variety of health risks, visceral fat, the second type of storage fat, has far greater potential to be more harmful.
What is visceral fat?
Visceral fat is a type of body fat that surrounds your organs in your abdominal cavity.
These fat cells hide between your abdominal organs and become overlooked when you use BMI to assess health or body density measurements. However, health professionals recognize visceral fat as a far more dangerous health threat than subcutaneous fat, and it’s considered a strong, independent predictor of all-cause mortality in men and women.
High levels of visceral fat, the hard-to-see fat, can be a true red flag for overall health. Visceral fat churns out inflammatory proteins that can stress the body, causing damage to many-body systems. This can lead to serious diseases such as cardiovascular disease, liver disease, diabetes, and other life-threatening conditions.
Sometimes, a person may not look overweight, but if their visceral fat levels are high, they can develop a condition called metabolic obesity. In this syndrome, visceral fat collected most often in the abdomen, correlates with high rates of type 2 diabetes, heart disease, and stroke.
With all this serious discussion on fat, you may now be wondering, how can I measure my body fat, or find out my body fat percentage? Keep reading.
How to measure your body fat percentage?
There are several ways to measure body fat percentage, and each method has its advantages and disadvantages.
- Tape Measure
- Skinfold Caliper
- Hydrostatic Weighing
A tape measure is a common tool to use for a general body fat calculation. In general, by measuring the circumference of various body parts: Neck, abdomen, and hips added in for women, specific circumference values can be calculated. Men and women can each identify a value, and then by knowing their height, can consult a body fat calculator ( found online) to generate an estimated body fat percentage.
Drawbacks to this method include errors in measuring and variables based on how much you’ve eaten recently and how tightly you pull the tape measure.
A skinfold caliper is an instrument that, gently pinches the skin and subcutaneous tissue to measure specific sites.
The standard for measuring body fat was once skin calipers. However, the usefulness of skinfold calipers has been called into question because, among other concerns, they only account for or report subcutaneous adipose tissue.
To utilize hydrostatic weighing a subject descends into a water tank until completely submerged. Now, weighing the subject with all lung air expelled, a new reading emerges. While accurate, this method is highly impractical, expensive, and uncomfortable.
Dual Energy X-ray Absorptiometry (DEXA)
Currently, “gold standard” methods include Dual Energy X-ray Absorptiometry (commonly known as DEXA). A DEXA scan entails a highly trained specialist directing two low-energy X-ray beams toward the subject’s bones. This method is accurate in terms of calculating body fat percentage, but it is extremely impractical, expensive, and not easily repeatable.
Bioelectrical Impedance Analysis (BIA)
Another method of body fat measurement that is rapidly evolving and gaining popularity is bioelectrical impedance analysis (BIA). BIA measures impedance by applying alternating low-level electrical currents through the water in the body.
The technology behind BIA models has advanced to the point that high-tech models are on par with the gold standard DEXA method. In contrast, the BIA offers superior affordability, convenience, and good test repeatability.
Though some BIA models in the past had questionable accuracy, the technology has advanced to the extent that the most cutting-edge devices offer accuracy on par with gold standard methods like DEXA but superior affordability, convenience, and repeatability.
Body Composition, Weight Gain and Weight Loss Takeaways
In sum, the study of body composition, including the recognition of the many different types of body fat, is a key component to your overall health.
Rather than thinking that you only need to lose (or gain) weight, perhaps it is more beneficial to assess the different types of body fat you have, and where those levels may be outside of a healthy range. By focusing on the types of fat present in your body, and where that fat exists, you can make informed decisions that greatly impact your health and well-being for many years to come.