Question Everything, Especially When it Comes to Health and Fitness

The 2,000 calorie per day diet. The 10,000 steps per day goal. The body mass index. These are just a few examples of things we have been told are measures or indicators of good health or healthy practices but are by and large arbitrary and oversimplified. Bodies are complex and complicated, and no two function exactly alike. Trying to standardize them in any way is an exercise in folly, and it allows for people who don’t live up to these standards to be marginalized and bullied.

Let’s take BMI, for example. Anonymous fat writer Your Fat Friend recently published a piece on the racist and questionable history of the BMI. It is an incredibly well-researched article, and if you didn’t already know that BMI was sketchy, you should definitely read it. To summarize, BMI is a statistical way of finding the “ideal” body size for a population; it was never meant to link the weight and health of an individual and is NOT a measure of how healthy a person is; it was developed by measuring only white men, excluding all women and all people of color. Two people with the same BMI could be in vastly different conditions. For instance, a runner could be the same height and weight as someone with a chronic health condition that limits their mobility. Their BMI would be the same, and thus they would be classified into the same category (underweight, normal, overweight, obese, or extremely obese). The only thing BMI can tell you is how your weight for your height compares to the weight and height of other people in the population (ie, white men). It cannot tell you how healthy you are. But because it was adopted by US health insurance carriers, and then physicians, as a way of determining who might be at higher risk of disease (and thus who was a greater risk to insure and who should be charged more money), it hangs on.

There was an article on NPR not too long ago about where the 10,000 steps per day recommendation came from. Turns out that it goes back to a decades-old marketing campaign in Japan for a pedometer. Somehow, that number was adopted in the US as a goal for good health. One study on that number concluded that older women really only need light activity, around 4,400 steps per day, to boost their longevity. And that doesn’t take in account all activity they may participate in. Also, the longevity benefit in that population topped out around 7,500 steps per day. As with most things in the health and fitness area, what makes sense for one person, doesn’t make sense for another. Trying to meet an artificially set goal like 10,000 steps (which is the default goal for fitness trackers like FitBits) is setting up some people for failure.

As for the 2,000 calorie per day diet? It is based on some very rough rounding from self-reported calorie intake surveys that helped form the basis of the 1990 Nutrition Labeling and Education Act. The FDA wanted consumers to be able to compare products for what percentage of daily intake of sodium, protein, fiber, etc the product made up. But that daily intake percentage had to be based on a standardized calorie intake. Ultimately, for reasons detailed in the article I linked, the FDA decided to use a 2,000-calorie diet as the baseline, noting that individual diets will vary. Somehow, though, that piece of data has become a goal for calorie intake, even though how much food your body needs is a complex interaction of age, size, activity, hormones, and metabolism, among other things.

Health messaging, especially in the US where lobbyists for various food industries (how many different meat and dairy recommendations have you heard?) are involved, is a minefield of bias and misinformation. Often, we’re only getting part of the story, and we don’t even know where the story is really coming from. The diet industry and lobbyists are very good at hiding behind scientists to put their “research” out for public consumption without context. Comparators and populations are left out of the percentages we’re fed. We don’t know who was tested, or how we compare to them, or how many people were actually studied. Yet, each time a new recommendation comes out or a standard measure changes (see the shift in BMI definitions in 1998), people immediately look at themselves first to see if they are “okay.” And then they look around at everyone else to see who is not “okay,” who doesn’t measure up. Usually, the answer is fat people.

When it comes to recommendations for better health, we all need a skeptical eye and a BIG dose of critical thinking. Before you are discouraged (or encouraged), take a look where the information is coming from if you can, and try to find out more about it. And definitely before you judge another person’s health or well-being or worth based on these recommendations, make sure you know where they are from and the history behind them. You’ll be surprised to find out they are often not based on real evidence.