Who is Tanita?

Tanita is a 70-year old Japanese firm that has been making precision scales for over 55 years. In 1992 they introduced the first body composition/analyzer scale to the professional market. In 1994 they started selling scales to the consumer market.

While their commercial scales are approved for industrial use, their consumer scales are FDA approved.

A few months ago I tried the Tanita TBF-410 Body Composition Analyzer.

The Tanita scales uses Bioelectric Impedance Analysis (BIA) technology to determine body composition. When you stand on the scale, a 50kHz, 800 micro amp current passes through your body. By measuring the impedance, or resistance to current, the system can measure body mass and composition.

I had the measurement done by a local physical therapy practice at a street fair in a local town. They were looking to drum up business with free measurements and I was looking to try one of these machines. In August 2012, I wrote a post, “What’s Your Number” about obesity and the methods of measuring body composition. In that post I wrote about Bioelectric Impedance Analysis (BIA) and the Tanita scales.

If you own a Garmin watch, you will be happy to know that Tanita scales are compatible with some Garmin watches.

Methods of Measurement

There are a variety of methods to measure body composition. They all have good and bad points.

The BMI test is widely ridiculed as being in-accurate and not worth the effort to calculate. While BMI does not account for body types the only cost to calculate BMI is a few minutes and some simple math. The NIH has a free calculator on-line and all you need to do is plug in your height and weight.

I still think the BMI calculator is a good place to start for most of us. The other methods of measurement are not as accessible.

The “gold standards” of body composition testing are the Dual Energy X-ray Absorptiometry (DEXA) and Hydrostatic Weighing. These “gold standards” are not generally available to the public and can be expensive. Please see my previous post, “What’s your Number”, for more details on these methods.

I tried to find a DEXA scan in the Boston area. Being the hub of medical research and having so many hospitals and medical professionals, you would think it would be easy.

I found one office that offered it only to their patients and a research facility that offered it only to research subjects. DEXA is commonly used to measure bone density, and as a diagnostic tool for women who may suffer from osteoporosis.

I didn’t qualify for any of the studies and do not have a condition that requires my bones to be scanned.

I haven’t found anyone offering the Hydrostatic Weighing procedure. It requires special equipment and as such, is probably expensive.

While BMI is easy to calculate, it is inaccurate. The “gold standards” are accurate but generally not available. I have studied and written about the Tanita system, so I knew it would offer some interesting data for me . The accuracy of the process may be disputable, but it was FREE and AVAILABLE.

The weigh in

They have different modes on the machine for different types of people. These include, Adult, Athlete and Wrestler. To qualify for Athlete mode you must get 10 hours per week of intense exercise and have a resting heart rate of 60 or less. Mine is usually around 50. As a runner I get 3-5 hours of intense exercise weekly, so I only qualified for the standard setting. I took of my shoes and stepped onto the scale.

I am 6’1″ and weighed 176.2 at the time. This gave me a BMI of 23.2. The Tanita gave me these additional details:

• Fat %                     14.3%
• Fat Mass               25.2lbs
• Fat Free Mass      151lbs
• Total body Water 110.6lbs

My desirable ranges are: Fat%  11-22% and Fat Mass 18.6 – 42.6lbs.

My results and analysis

While the accuracy of the Tanita system may be debatable, the system is FDA approved.

The measurement showed my fat % (14.3%) and pounds (25.2lbs) were on the low end of the desirable range. As a runner I was happy to see I that my hard work was paying off.

My fat-free mass is 151lbs, which means it would be very difficult, and probably unhealthy, for me to get near 160lbs. I would need to get my body fat down to the 5% range.

Over the summer when I was in marathon training mode I hit 165 on the bathroom scale a few times. I rarely hit 170 all summer and into the fall. Only around the holidays did I get over 170.

I know that my bathroom scale is not as accurate as a doctor’s office scale or the scale built into the Tanita. My weight is probably 2-5lbs more than what my home scale shows. With this assumption, I probably did get into the 11-12% body fat range over the summer. I’m probably in the 12-13% range now.

Conclusions

Using a single data point is not a valid method of determining anything. I think that access to one of these scales over time could be interesting and useful to me. A basic Tanita scale starts at $89.99 and range up to $632.99. I paid $24.99 for my current scale and my weight changes slightly depending how I arrange my feet on the scale. Maybe this year I’ll upgrade to one of these more accurate scales.

As a runner I tend to keep an eye on my weight. It would be nice to know how much of my weight is fat and how much is muscle added through marathon training.

Questions

Have you ever had a DEXA or Hydrostatic measurement?

Have you ever used a Tanita system?

Would you pay over $100 for a scale?

Is your weight at the doctor’s office significantly higher than your weight on your bathroom scale?

Disclaimer – I did not receive compensation from Tanita or the physical therapy office that performed my analysis.

Run well my Friends,

Andy

© 2014 Andrew Nagelin