January 30, 2012

BMI – Part II

Posted in Weight Loss tagged , , , , , , at 7:04 pm by Dr Michelle Torrance ND, LAc

Aesthetically, we all know what being overweight looks and feels like. But do you know what is happening on the inside?

Adipocytes, aka fat cells, are commonly visualized as fluffy square-like cells that are plumped up by the fat within them. For many years, adipocytes were thought of as fairly inert and unexciting storage units. Current research, however, is showing that these cells do far more than just sit there and store our excesses for future use.

Nowadays, a fat cell is being seen as an extension of our endocrine (hormone) system. A good example of this is estrogen and cortisol production. In overweight women, a measurable amount of estrogen is created by the aromatase secreted by the fat cells. In my practice, I have often seen the phenomenon where a peri- or menopausal woman will lose weight and have an increase in her night sweats or hot flashes, or some mild hair loss. Her body eventually adjusts to the lower amount of estrogen and the symptoms resolve. Aromatase can have a multitude of effects depending on the area of fat distribution. Aromatase also creates excess cortisol. Excess cortisol interferes with proper insulin secretion and sensitivity. This creates blood sugar problems (hyperglycemia and Type II Diabetes) as well as increased truncal obesity, greater deposition of visceral fat and increased health risks. In other words, excess fat is creates an environment that makes it easier to be fat.

Now, how do adipocytes relate to BMI? If your BMI number is greater than 30, then you are for sure carrying around more body fat (aka adipocytes) than you should be.

Men and women often disagree with where the “perfect” body weight is on the chart. Most women’s projection of their ideal body weight usually fits into the “Healthy” weight range pretty easily, or is just above at a BMI of 25-26. Most men would disagree with a BMI of 19-24.9. This is especially true for men who have a lot of muscle. To be in the “Healthy” weight range of BMI, they find it too lean and too difficult to maintain. Generally, many men would be very comfortable within the “Overweight” range, 25-29.9. Anything higher than that and the health risks certainly outweigh the benefits.

Naturally, there are exceptions to every rule, but they are few and far between here. This is not the place to use the “I’m just big boned” excuse to justify being in a higher bracket. Probable exceptions include body-builders, elite athletes and those very few individuals who genetically carry a higher amount of bone and lean muscle mass. The vast majority of us, however, fall within the guidelines for the general population.

 

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January 28, 2012

BMI – What does it really mean?

Posted in Weight Loss tagged , , , , , , at 12:54 pm by Dr Michelle Torrance ND, LAc

We’ve all looked it up – plug in your height and your weight and you get a number. http://www.nhlbisupport.com/bmi/

But what does it mean? You can reference the table that is usually attached, and see where you fall in the graph. You can look at the calculator’s recommendation about where you “should” be. You can look at the titles, “Healthy”, “Overweight“, “Obese” and see which category relates to you.

But the question really is, what do all those definitions mean to you?

Part I of the Answer

Let’s define BMI. Essentially, all it is is a height/weight ratio. It is very broad in its scope and its only purpose is to give an easy to use guideline regarding healthy vs. unhealthy weight. The higher the your number, the higher your health risks from weight and obesity related diseases.

What BMI doesn’t tell you: It doesn’t estimate your body fat. It can’t tell you how much abdominal or visceral fat you carry. It doesn’t predict your cardiovascular risks. It doesn’t care about your body composition.

What BMI does tell you: People with bigger numbers tend to be more sick. The higher the number, generally, the larger percentage of fat a person carries. The difference between “Healthy” and “Overweight” is fairly mild from a morbidity (the rate of incidence of disease) and mortality (death) point of view. But past that…”Obese”, “Morbid” and “Super”… some serious problems begin to arise.

Part II will discuss some of the metabolic effects that extra fat cells (adipocytes) create, and Part III of this posting will discuss some of the ways we can personally change these outcomes!