Unlike fat stored on the hips and thighs, fat around the middle produces substances that can pose serious health risks.
Regardless of the shape of your body, excess fat is not good for your health. But balloon bags and tummy tuck are not equivalent. When it comes to body fat, location matters and every year brings new evidence that fat deep in the abdomen is more dangerous than the fat you can pinch with your fingers.
In most people, about 90% of body fat is subcutaneous, which is in a layer just below the skin. If your belly stings, the fat that feels soft is subcutaneous fat. The remaining 10% – called visceral or intra-abdominal fat – is handy under the firm abdominal wall. It is found in the areas around the liver, intestines and other organs. It is also stored in the omentum, an apron-like tissue flap that sits under the belly muscles and covers the intestines. The fat gets harder and thicker as it fills with fat.
Although visceral fat is only a small part of body fat, it is a key player in a variety of health problems.
As women go through the middle ages, their proportion of fat to body weight tends to increase – more so than in men – and fat storage begins to favor the upper body over the hips and thighs. Even if you don’t gain weight, your waist can increase by inches as your visceral fat pushes toward your abdominal wall.
Where’s the fat?
Visceral fat is found in the spaces between the abdominal organs and in a tissue apron called the omentum. Subcutaneous fat is located between the skin and the outer abdominal wall.
The problem with visceral fat
Body fat, or adipose tissue, was once seen as a little more than a storehouse of fat that was passively waiting to be used for energy. But research has shown that fat cells – especially visceral fat cells – are biologically active. One of the most important developments [since the mid-1990s] is the awareness that the fat cell is an endocrine organ, which secretes hormones and other molecules that have far-reaching effects on other tissues.
Before researchers recognized that fat acts as an endocrine gland, they believed that the main risk of visceral fat was to influence cholesterol production by releasing free fatty acids into the blood and liver. Now we know that the story is much longer. Researchers have identified a number of chemicals that link visceral fat to a surprisingly large variety of diseases.
Subcutaneous fat produces a higher proportion of beneficial molecules, and visceral fat a higher proportion of molecules with potentially harmful effects on health. Visceral fat produces several proteins called cytokines, which can trigger low-level inflammation, a risk factor for heart disease, and other chronic conditions. It also produces a precursor to angiotensin, a protein that causes blood vessels to contract and blood pressure to rise.
A measuring tape is the best option at home to take into account visceral fat. Measure your waist at the navel – not the narrowest part of your torso – and always measure in the same place. (According to official instructions, the bottom of the measuring line should be level with the top of the right hip bone or ilium – see illustration – at the point where the ilion intersects a line descending vertically from the center of the armpit.) Do not aspirate your bowel and do not pull the band tight enough to compress the area. In women, a waist circumference of 35 inches or more is generally considered a sign of excess visceral fat, but this may not apply if the overall body size is large. Instead of focusing on a single reading or an absolute limit, be careful if your waistline increases (your pants become tight at the waist?). This should give you a good idea if you are getting unhealthy visceral fat.
From fat to disease
Visceral fat can be measured in a variety of ways. CT scans and whole-body MRI scans are the most accurate, but they are expensive and rarely available, so investigators often use estimates based on waist circumference or waist size in proportion to height (see “Checking the Bowel”). To make sure it doesn’t just measure general obesity, researchers are also checking to see if a person’s waist circumference is greater than the average body mass index (BMI).
Visceral fat is involved in a number of chronic conditions, including:
Cardiovascular disease. Several studies have documented this effect. For example, a large study of European women between the ages of 45 and 79 found that those with the largest waist (and those with the largest waist size) were more than twice as likely to develop heart diseases. The risk was still almost double even after adjusting for several other risk factors, including blood pressure, cholesterol, smoking and BMI. Even in healthy, non-smoking women, every 2 inches of extra waist size increases the risk of cardiovascular disease by 10%.
A higher volume of visceral fat also has a detrimental impact on a few other risk factors for heart disease. It is associated with higher blood pressure, blood sugar levels and triglyceride levels and lower HDL (good) cholesterol levels. Taken together, these changes, known as metabolic syndrome, pose a serious risk of cardiovascular disease and type 2 diabetes.
Dementia. Researchers at Kaiser Permanente found that 40-year-olds with the highest levels of abdominal fat compared to those with the least abdominal fat at that age were almost three times more likely to develop dementia ( including Alzheimer’s disease) to the middle of them. 70s to early 80s. Dementia was not associated with an increase in thigh size.
Asthma. In a large study by California teachers, women with high visceral fat (a waist circumference of more than 35 inches) were 37% more likely to develop asthma than women who were shorter. their weight was normal. The risks were highest for women who were both tall and overweight or obese. Investigators believe that belly fat increases the risk of asthma more than other pounds because it has inflammatory effects throughout the body, including the airways.
Breast cancer. A combined analysis of several studies found that premenopausal women with abdominal obesity (the largest waist size in proportion to their height) have a higher risk of breast cancer. Large waistline has also been linked to the risk of breast cancer among postmenopausal women, but this effect was not significant once the BMI was considered.
Colorectal cancer. People with the highest visceral fat are three times more likely to develop colorectal adenomas (precancerous polyps) than those with the lowest visceral fat. The relationship was found after many other risks were considered. The researchers also confirmed that adenomatous polyps in the colon are associated with insulin resistance, which may be the mechanism that increases the risk of cancer.
How to lose (and prevent) visceral fat from the abdomen
Where you tend to gain weight depends on genes, hormones, age, birth weight (younger babies add belly fat more easily later in life) and whether you have had children (women who have given birth tend to develop more ). visceral fat than women who do not have).
As young adults, women have on average less visceral fat than men, but that changes with menopause. You can’t change your birth weight or eyelashes and you can’t hold back menopause. But there are several ways you can minimize the accumulation of visceral fat. The good news is that because it is more easily metabolized into fatty acids, it responds more effectively to diet and exercise than fat on the hips and thighs. Here are some approaches that can help:
Keep moving. Exercise can help reduce waist circumference. Even if you do not lose weight, you lose visceral abdominal fat and gain muscle mass. Engage in at least 30 minutes of moderate-intensity activity on most days, such as walking or cycling at a regular pace. Also, create opportunities to add movement to your routine tasks. For example, park away from your destination and walk the rest of the way, take the stairs instead of the elevator, and stand while you talk on the phone.
Studies have shown that you can help cut down on visceral fat or prevent it from growing by both aerobic activity (such as brisk walking) and strength training (weight training). On-the-spot exercises, such as the abdomen, can tighten the abdominal muscles, but will not touch the visceral fat. Exercise can also help prevent fat from returning.
Eat right. Choose a balanced diet that helps you gain and maintain a healthy weight. Avoid products that seem to encourage the deposition of fat on the abdomen, especially simple sugars, such as foods and beverages sweetened with fructose.
Do not smoke. The more you smoke, the more likely you are to store fat in your abdomen rather than your hips and thighs.
Go to sleep. Too little is bad. A five-year study found that adults under the age of 40 who slept five hours or less a night gained significantly more visceral fat. But not too much is good – young adults who have slept more than eight hours have added visceral fat. (This relationship was not found in people over the age of 40.)
Take care of your condition. Middle-aged women who are more hostile and have had more depressive symptoms tend to have more visceral fat, but not more subcutaneous fat.
Forget the quick fix. Liposuction for the cosmetic removal of fat does not reach the inside of the abdominal wall.
Image: UserGI15994093 / Getty Images
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