Your Fat (no, not YOU'RE Fat)

While attending medical school at the University of Cincinnati back in the 1970s, the faculty would occasionally warn us that “…about half of what we’re teaching you will be proven wrong in five years.” In hindsight, although that was a bit of an exaggeration, they were making an important point: knowledge grows, insights multiply, and soon science and medicine evolve to new understandings and practices. In other words they were saying, never be complacent and think that the answer has been found. Science is a process, not a religion.

One particularly good example of a changing scientific landscape is our knowledge and understanding of body fat (also know as adipose tissue). Three decades ago we were taught that fat was a dumb tissue unlike those making up sophisticated organs like the kidney, brain or heart, and it merely served as a depot for energy storage. The cells making up this tissue are called adipocytes and we now know they are far from dumb, and further, when enough of them gather together in certain places in your body this fat can actually control your destiny...no foolin'!

Please see illustration below:

Graphic from hypericum.com

The midsection fat (slang terms abound, e.g., jelly belly, beer gut, front porch, muffin top, bay window, love handles) is actually composed of two very different types of fat: the subcutaneous fat that lies just below the skin and pictured as light blue and the visceral fat which lies underneath the abdominal wall (which includes the muscle layer) and is pictured in dark blue. The subQ fat is the soft material that you can easily grab and hold--that is, unless you have a near-perfect six-pack or "washboard" set of abdominal muscles.

Below you can see two abdomens...the guy above has essentially NO subQ abdominal fat whereas the guy below looks like he put a few pounds on since college.


The image above is from here, and the one below is from here.

What has been learned in the past two decades is that the visceral fat, that is, the adipose tissue within your abdominal cavity actually acts as an endocrine organ and can have a significant effect on your metabolism. This intra-abdominal fat significantly increases the risk for cardiovascular disease, hypertension and diabetes.

One reason that the visceral fat has such a profound effect on our metabolism and disease risk is that the blood from this visceral fat drains directly into the liver, our master metabolic organ. Through the hormones that this fat secretes, it controls--among other functions--how our body reacts to the insulin that our pancreas puts out. Increased visceral fat increases the cell's resistance to the action of insulin; the pancreas senses this, and then ratchets up the amount of insulin it secretes. When the pancreas cannot keep up with the increased demand for insulin caused by this insulin resistance, type 2 diabetes develops.

The distribution of body fat is dependent on several variables including genetics, metabolism, hormonal balance, the presence of certain diseases, aging and sex. For example, when women go through menopause their fat distribution shifts from the periphery to the center, and they often get belly fat similar to that of overweight men.

Ok...so what does this all mean?

• First, understand that sit-ups will not give you a spot-burn and get rid of belly fat; you cannot tighten up what you can grab above the muscle layer--you must lose it through negative calorie balance


• If you distribute excess fat more or less evenly over your body and do not concentrate it in your abdomen you are less at risk for diabetes and cardiovascular disease


• You will lose fat in the order that you put it on--last on, first off


• If you have a family history of diabetes, hypertension, heart attacks or other cardiovascular disease, reducing abdominal fat should become a serious personal goal

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