Overweight vs. Excess Fat: Is Your Scale Lying to You?

Even in case your weight looks normal, you're storing an unhealthy amount of visceral fat.

For many years, body mass index (BMI) has been the gold standard for predicting obesity-related heart disease risk. But this easy tool doesn't all the time tell the entire story. It calculates your body fat percentage based in your height and weight (see /bmi-calculator). But the formula doesn't predict how and where your body stores its excess fat — a distinction that's vital for cardiovascular health. By some estimates, BMI misclassifies about 50% of individuals as being at high risk of obesity, meaning chances are you’ll be chubby even while you're not chubby.

The Secret Life of Belly Fat

In individuals who don’t have an adequate quota of accessible fat storage cells (or those whose adipose tissue is already full to capability), fat particles travel through the bloodstream and are deposited within the liver, muscles, and tissues. and accumulate in other organs, which normally don’t contain fat. It also accumulates visceral or “belly” fat — a fat distribution pattern that's particularly dangerous to your health (see “Who Has Visceral Fat?”). Visceral fat is related to insulin resistance and other metabolic abnormalities. “It also stimulates the release of inflammatory substances that damage arteries and help set the stage for heart disease,” says Dr. Mentzors.

Who suffers from visceral fat? The tendency to build up visceral fat is driven by genetic, ethnic and gender differences. For example, individuals who inherit two copies (one from each parent) of a mutation in a gene involved in fat metabolism usually tend to have a better amount of visceral fat than individuals with just one copy. Those with no copies of the gene change are less more likely to develop heart disease – even in the event that they are obese. Indians and South Asians have a better than average prevalence of abdominal obesity. And white men and black women accumulate more visceral fat than black men and white women.

Obesity and aging

With age, people are inclined to lose muscle tissue, especially the style of muscle fibers that produce speed and strength. Fat often accumulates inside the remainder of the muscle tissue, causing your body fat percentage to extend even when your weight stays constant. This scenario is closely related to inflammation throughout the body and the chance of diabetes. It also can explain why your BMI measurement doesn't accurately reflect your health risks.

Evidence suggests that waist circumference and waist-to-hip ratio are higher indicators of metabolic health than BMI. Even amongst individuals with the identical BMI, those with a bigger waist (defined as greater than 40 inches for men and 35 inches for ladies) have a significantly higher risk. Also, individuals who carry their weight on their hips and thighs (in a “pear” shape) have a lower waist-to-hip ratio and a lower risk of heart disease than individuals with abdominal obesity. (an “apple” shape); See “Measuring Your Midsection.”

Measuring your midsection To measure your waist accurately, exhale and wrap the measuring tape around your bare stomach just above your navel (belly button). Do not suck into your gut or pull the tape so tight as to squeeze the realm. To calculate your waist-to-hip ratio, first measure your hips by placing a tape measure across the widest a part of your hips. Place the tape measure level. Then, divide your waist size by your hip size.
Measurements that indicate high risk.	waist (inches)	Waist to hip ratio
Women	35 or more	0.9 or higher
Men	40 or more	1.0 or higher

What must you do about visceral fat?

People with abdominal obesity – even in the event that they aren’t chubby – can reduce their risk of heart disease with regular exercise and healthy eating habits. “Reducing the total amount of fat in your body frees up storage space for fat particles in areas that are associated with lower metabolic risk,” says Dr. Mentzroz. This is why losing 7% of your total body weight helps reduce the chance of heart disease: essentially the most dangerous visceral fat disappears first.

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