BoomerGirl Diary

Dear Crabby:

Is BMI an accurate measurement of obesity, and do those body fat calipers really work? Just when I thought I was becoming a sleek and fit BoomerGirl, I joined a fitness club and subjected myself to a "fitness evaluation" by a personal trainer. She measured my bust, waist, and hips. I was wearing a sports bra, t-shirt, and sweats ... she measured over all that fabric! AND I was instructed to "relax" and stop holding my stomach in. I am sure this made my breasts compressed and flattened, waist much larger, and hips enormous.

That evening I nearly killed myself in the sauna trying to sweat off the extra poundage.

What is your take on all of this measuring and calculating?

I've already joined the gym ...

D.K., Kansas

Dear D.:

Weights and measures — boy are they an inexact science! Your experience is not unusual by any means. And no, I doubt that the measurements were accurate. And was she a really tiny thing, in tight workout clothes? Not an ounce of fat on her? Did you have an urge to take the calipers and just pinch ... oh, sorry! Got carried away there....

There are lots of ways to measure the body. Let’s talk about a few.

Are you big-boned? Remember body frame/weight charts? I am 6 feet tall, and (ahem) sturdily built. Yet my wrists and ankles are spindly little twigs — I measure as a “small” frame! Pretty worthless, in my book.

Then there are those machines that look like scales that you stand on or grip with your hands — they are supposed to send a current through the body and somehow measure the fat content. Hard to believe they are accurate ... if my home electronics are any indication, glitches and bugs run rampant! They seem gimmicky, like those vibrating-belt weightloss machines of yore.

The insurance height/weight tables were a nightmare, and didn’t account for fit, muscular women. These have been mostly abandoned, thank god. Those didn’t even list weights for women over 5’11”—once again, old Crabby was relegated to “Freak” category!

Body fat calipers are popular in gyms, but there appears to be no real standardized way to use them. Also, we all know someone who is skinny in most areas, chubby in one or two. If these are the pinch-an-inch spots picked, well, then, the results are skewed. And they certainly should not be used over clothing, although that makes a good defense! (“30 percent? — oh, that was just the heavily quilted down jacket she measured over, I’m sure I’m closer to 20!”)

The only real way to check body fat is by weighing the body in and out of water in a special lab, such as the one at a research hospital or university. Cripes, hard to find AND you have to get into a swimsuit in front of strangers! This yields a measurement that is accurate and scientifically proven. And usually depressing.

“Normal” body fat percentage for women is about 22-25 percent. But this is just a number. And so is BMI, which is the most popular measurement these days. Some medical offices check it at each visit. The Body Mass Index, or BMI, is a relationship of weight to height, and gives you a number that corresponds to a category of underweight, normal, overweight, obese, etc. In theory, these categories might help predict health risk, but the data is still a little soft on that. The BMI also does not take into account muscle mass, so a bodybuilding woman might show up as “overweight” on the chart.

Figure yours here: http://www.ahealthyme.com/topic/bmi

The waist-to-hip ratio is another measurement that is getting a lot of press. As you probably know, women who carry their weight in the belly (apples), even rather thin women, are at higher risk than women who have a little “junk in the trunk” (pears). To figure this ratio, divide your waist measurement by your hip measurement. Ideally, women should have a waist-to-hip ratio of 0.8 or less. Women with a ratio over 0.8 appear to be at greater risk for weight-related diseases such as diabetes and heart disease.

Figure yours here: http://www.ahealthyme.com/topic/waisthip

In our culture, with its hyperacute focus on weight, I imagine most people who need to lose weight know it. The measurements might provide motivation, I guess, although usually they just bum you out. Repeated measurements can gauge progress, if you are intent on using them. They can also be a discouraging distraction, or a complete error, as you have pointed out.

For my own weight loss efforts, I took a quick look at BMI (fair) and waist-to-hip (yikes!) to give me an idea of where I am. Since then, I just try to focus on how I feel, how my clothes fit, and my waist measurement, which has been stubbornly static since menopause, despite a 20-pound weight loss. And, in truth, we’d probably all be better off if we started accurately measuring and weighing our food portions, instead of ourselves! So, thanks for the question, D., it’s a good one. And now, throw away the tape, the chart, and the calipers, and go take a walk. A long, brisk one.