Visceral Fat and Why We Should Be Concerned With It
The correlation between obesity and disease is well established. Diabetes and heart disease are two of the most prevalent conditions associated with obesity. The conventional method of determining levels of obesity is Body Mass Index or BMI for short. It is a formula based on your weight and height. You can have your BMI automatically calculated online here. If you are in the range of 18.5 to 24.9, you are considered normal. Below 18.5 is deemed to be underweight, above 24.9 is considered overweight. BMI below 18.5 and above 24.9 are both considered unhealthy. Thirty and above is considered obese. Unfortunately, BMI has limitations. Muscular but otherwise lean individuals may have a BMI in the overweight range. Pregnant women will skew high. Children may not have reached their growth potential and appear to be underweight. (1) Body type also affects BMI. One may be lean but have pronounced fat in one region only, a condition known as ectopic fat distribution, giving them a healthy BMI.
One specific form of ectopic fat distribution is known as visceral or abdominal fat. The location of visceral fat is inside the abdominal wall around the organs as opposed to being just under the abdominal skin. When there is enough fat to show, the belly appears smooth and rounded as in pregnancy. Subcutaneous abdominal fat tends to droop over the pants, making it somewhat easy to differentiate from visceral fat. The two can occur together making the determination more difficult. Insulin resistance (type 2 diabetes) and heart disease are associated with visceral fat. (2) Increasing BMI alone without taking into account where the fat resides is associated with an increase in the risk of high blood pressure, poor cholesterol and triglyceride profiles, type 2 diabetes, heart disease, gallstones, and certain cancers. The problem arises that when just looking at BMI, some very obese patients show no clinically measurable markers of disease, whereas patients with healthy BMI demonstrate illnesses associated with obesity, leading many clinicians to shun using only BMI as a reliable predictor of disease. (3,4)
In the Mid-eighties, Gothenburg and associates linked a high waist-to-hip ratio (WHR) to an increased risk of developing heart disease and diabetes. (5,6) The shortcoming of the WHR method is that it cannot accurately differentiate between the belly fat under the skin to the visceral fat around the internal organs, leading to confounding results. 3D imaging enabled researchers to make distinctions between the two. (7) In 2002, Ross and colleagues determined that in patients with similar BMI, those with higher visceral fat could not handle glucose challenges as well, establishing that they were at higher risk for developing type 2 diabetes. (8) In 2009 Mahabadi et al. found that patients with heart disease had greater amounts of visceral fat when compared with control subjects. (9)
The risk for developing heart disease and type 2 diabetes requires measuring several markers like cholesterol, triglycerides, blood pressure, etc. that can become costly when added up. Lemieux, Poirier, and Despres have developed a quicker and cheaper method by measuring increased waist circumference combined with elevated fasting triglyceride concentrations. They call this combination the hypertriglyceridemic waist, and they propose that it could be used as a screening to identify patients likely to be characterized by high fasting insulin levels, elevated apolipoprotein B (a cholesterol-type attribute) and an increased proportion of small LDL particles, all of which are indicative of metabolic issues associated with diabetes and heart disease. (10)
Today, we have precise imaging for body composition through the use of DEXA Scan technology that gives you exact measurements of fat and muscle distributed around your body. There are multiple DEXA Scan locations throughout the US, Australia, and Great Britain. You do not need a referral from a physician to obtain one, so those of you who are curious can find out precisely what your fat distribution is. Since visceral fat may not be apparent from the outside, DEXA Scan technology can let you know if you are at risk sooner than your eyes or the bathroom scale. The prices vary from location to location, but the location near me charges $150. (11)
Diagnosis and treatment of blood sugar issues and cardiac problems is a complicated business and should be left to the professionals. However, even if the scale tells you that you are a healthy weight, but you are sporting a belly bulge, I suggest you visit the doctor to assess your risks for developing blood sugar issues, cholesterol issues, high blood pressure, metabolic syndrome, and the like.
Recommendations to lower visceral fat and general obesity include dietary changes and exercise. Interestingly, fructose influences more visceral fat deposition. One study gave either glucose or fructose to two groups. The fructose group had an increase in visceral fat. (12) You don’t have to give up fruit, but you should give up high fructose corn syrup contained in processed food. While you are at it, give up all processed foods! Ross and Janiszewski also found that regular physical activity and exercise could induce a substantial reduction in visceral adiposity, even in the absence of weight loss. (13) Whatever diet chosen for weight loss and health, it should exclude all processed carbohydrates, industrial seed oils like corn, canola, and soybean oil, and include whole minimally processed foods and animal products.
