Body Fat Composition
Often you go to your doctor's office and they get your weight. The doctor tells you if your weight is healthy or not based on your BMI.
Body Mass Index
But is your BMI an accurate assessment of your health?
Obesity is an excess accumulation of fat. The definition is based on criteria measured by the body mass index.
Using the following formula, you can calculate the Body Mass Index (BMI).
BMI = Weight (kg)/(Height (m)2
Here are the general BMI categories:
- Underweight: BMI less than 18.5
- Normal weight: BMI between 18.5 and 24.9
- Overweight: BMI between 25 and 29.9
- Obesity: BMI equal to or greater than 30
BMI is not an accurate assessment of body composition, just as body weight is not an accurate indicator of health without more information.
Body Composition
Skinny fat is a coined term used to describe people in the general population who have a normal weight and look like they are healthy, but low muscle mass, poor diet and horrible lifestyle choices can contribute to poor health outcomes for low body weight individuals.
The Journal of Clinical Endocrinology & Metabolism discovered that individuals with more body fat and less lean muscle mass had a higher risk of all-cause mortality, even after accounting for factors like age, sex, and smoking.
According to a study published in the Journal of Clinical Endocrinology & Metabolism, the optimal body fat percentage for men is between 8% and 19%, while for women, it's between 21% and 32%.
Body composition is the measure we should use as the standard to understand and assess your individual health. Too often, the assumption is weight loss by itself equal improved health. It is important to understand weight loss as it relates to the percentage of fat versus muscle.
For example, when you lose weight rapidly through extreme cardiovascular exercise with a calorie deficit, the weight loss will be more muscle that fat, especially without resistance training. If the weight loss results from more muscle loss than fat, this may prove more detrimental to your health.
The three keys to body composition
1. Muscle mass
2. Fat mass
3. Distribution
Even though a higher fat percentage to overall body weight is associated with poor health outcomes, the distribution of fat around the abdomen has a higher risk of death. A recent study found that for every 25 cm2 increase in visceral fat area, there was an associated 13% increase in all-cause mortality risk.
British Journal of Sports Medicine found that individuals with higher levels of visceral fat (the type of fat that surrounds your organs) had an increased risk of cardiovascular disease and type 2 diabetes.
The range of health problems stretches further and includes:
Insulin resistance
Joint Issues leading to severe pain and osteoarthritis.
Metabolic syndrome
Non-Alcoholic Fatty Liver Disease
High blood pressure, which can lead to strokes, cardiovascular disease and strokes
Cancers like colon, breast, endometrial, pancreatic and ovarian cancers
Sleep Apnea which leads to poor sleep quality and many medical problems
Reduced life span
Methods for measuring
Bioelectrical impedance Analysis
A device measuring the impedance (resistance) of electrical flow through body tissues. It works on the principle that different tissues in the body conduct electrical currents differently. Lean tissues, such as muscle, contain more water and electrolytes and thus conduct electricity well, while fat, which has lower water content, resists the flow of electrical current.
BIA devices then use mathematical equations, along with factors like age, gender, and sometimes height and weight, to estimate body composition. The output typically includes information on body fat percentage, lean body mass, and sometimes hydration status.
DEXA
Dual-Energy X-ray Absorptiometry, is a medical imaging technique used to measure bone density and body composition. Originally developed to assess bone mineral density for osteoporosis diagnosis and management, DEXA has expanded its applications to include the measurement of fat and lean tissue mass.
Skinfold thickness measurement
Skinfold thickness measurement is a method used to estimate body fat percentage by measuring the thickness of a fold of skin and subcutaneous fat at specific anatomical sites.
Hydrostatic weighing
Hydrostatic weighing is based on the assumption that lean tissue is denser than water, while fat tissue is less dense. The method is one of the more accurate ways to assess body composition.
Causes of increased visceral fat
You can boil down the causes of visceral fat accumulation to simple factors.
Poor diet high composed of processed carbs/sugars
Sleep deprivation and lack of quality sleep
Lack of activity
Stress
Summary
There are plenty of individuals walking around thinking because their weight is normal, that means they are healthy. Do not get fooled into a level of health complacency because your weight or BMI are in the normal range or above the normal range.
Understanding body composition is crucial for an accurate assessment of your health, especially when combined with body fat distribution. If living longer and enjoying a quality life is the goal, then taking action to learn about this aspect of your body's health is vital. What we manage now can ensure a better life in the future.