The Myth of the “Ideal Weight”

By Michael Applebaum, MD, JD, FCLM

Ideal.  What is ideal?

Well, if you look in the dictionary, which I find to be a pretty good reference for word meanings, nothing is ideal.  You'll find definitions like: 

A conception of something in its absolute perfection. 2. One that is regarded as a standard or model of perfection or excellence. 3. An ultimate object of endeavor; a goal. 4. An honorable or worthy principle or aim. --i·de·al adj. 1.a. Of, relating to, or embodying an ideal. b. Conforming to an ultimate form or standard of perfection or excellence. 2. Considered the best of its kind. 3. Completely or highly satisfactory: The location of the new house is ideal. 4.a. Existing only in the mind; imaginary. b. Lacking practicality or the possibility of realization.

These are from the American Heritage Dictionary and are representative of the definitions found in other sources.

"Ideal" is conceptual.  It is not practical, it is not achievable.  Among the last things we need is a health and fitness goal that is impractical and unattainable.

In fact, there are a lot of representations in the weight debate whose underpinnings are faulty; “ideal weight” is merely one of them.

Have you ever asked yourself how the impossible “ideal weight” came about?  I thought not.  So I’ll tell you.  (By the way, this is closely related to the story of the weight loss myth, which will be the topic of another rant.)

At the turn of the 20th-century the life insurance industry was looking to make more money.  Imagine that.  In furtherance of this objective, it undertook a project to identify factors which may be associated with premature mortality.  The industry was hoping to screen applicants using these factors.  The point being that if the industry could identify those at greater risk of early death, i.e., those likelier to cost it money through a policy pay-out, then it could charge them more up front or deny them coverage altogether so the industry's bottom line could improve.

One factor which could be easily and readily quantified was weight.  The insurance companies undertook a statistical analysis of their policyholder’s body weight information that their physicians had collected.  The intent was to determine whether there was a statistically significant relationship between body weight and the risk of mortality.  From this data, in 1897, the first height-weight table was generated.

Between 1897 and 1912, these height-weight tables were sex and age specific stating the "average" weight of policyholders for each gender over a given age range.  The data were obtained from policyholders whose ages spanned from approximately 15 to 70 years and were interpreted as follows: "Average" weight was always recommended.  "Overweight" included all individuals who exceeded a given weight range for age.  Persons who weighed 20 percent or more than average for their age and gender were penalized with higher insurance rates.

And so began the reliance on the height-weight tables.  Above average weight was generally considered bad whether it was from muscle or fat.  It is fascinating to consider that no distinction was made between the two.

In 1942, a shift of tectonic proportions occurred in the obesity/overweight conversation.  In that year, the Metropolitan Life insurance company published a new table for women (a new table for men was published in 1943).  The nomenclature had changed.  The weights were not given as average weight but as "ideal" weights.  And unlike prior tables, the weights for a given height no longer varied by age.  Instead they varied by a new, more arbitrary and uncertain “standard” called "frame size" (small, medium and large).

So how was this "ideal weight" determined?  The statisticians had noticed that an increased mortality in persons over the age of thirty was associated with weight increases over the average.  Thus, it was assumed that the ideal weight was the average weight in 20-to 29 year olds and that this was the weight one should maintain throughout one's life.

Until these new tables generated in the 1940s, the life insurance tables suggested that the best weight was the average weight for one's height, age and gender.  However, with the new tables, the age variable was deleted and the subjective determination of frame size was added.

Not very ideal, is it?

So why tell you all this?  A couple of reasons:

1.         To disabuse you of the notion of your "ideal weight” as determined by some chart.  My recommendation is don't buy that line.

2.         If you seek the assistance of a health care professional or personal trainer or anyone else and they say based on some chart that they are going to get you to your "ideal weight,” run, don't walk, to someone else.

Coincidentally, I went to my health club today to work-out and what did I see?  The absolute fanciest scale in Creation.  This thing is the Lamborghini of scales.  Flashing lights, high tech design, sleek look.  So what does it do to merit so pretentious an appearance?  It automatically determines your height and weight, then gives you a read-out of, among other things, you "ideal weight"!  For fifty cents.  I’ll keep my four bits, thank you.