Maybe it’s those inane but oh-so amusing infomercials on cable TV or the unrelenting pop-up advertising on the internet. But you probably believe as I do: If something seems too good to be true, it is.

Such belief began well before the advent of infomercials or the internet, though. By the early seventeenth century, a biblical allusion to one of the 12 apostles was created for skeptical people who refuse to believe in something without proof: a doubting Thomas.

In the twenty-first century, however, everybody including Thomas needs to move to Missouri, the Show Me state. Yet when it comes to your diet, being a suspicious Susan (there will be no gender bias in this column) or a doubting Thomas is simply not good enough. That’s because a doubting Thomas initially doubts, but then believes once proof is provided.

But what’s truly proof when it comes to your diet?

It’s surely not the loss of weight during the first weeks of adopting a new one. Any significant reduction in calories, regardless of how unhealthily it’s accomplished or how ill-suited it is for the long term, works for a while.

It’s surely not an increase in energy or mental acuity when you start consuming a single so-called superfood — or even a group of them. It’s impossible to isolate an improvement like this to a single variable. That your job has been less stressful lately or that you’ve been going to bed earlier may be the real reason or play a large part.

So if it’s not “proof,” what can you rely upon to guide your dietary decisions? The results of scientific research performed at highly regarded universities? The fact that those results merited publication in highly regarded journals?

Maybe yes. Maybe no.

It all depends upon something so obvious that you’ll probably roll your eyes as you read it. You can indeed learn a great deal from published research — provided you don’t forget that you did not take part in it.

Obvious or not, I forget this at times. You may, too.

Consider the research conducted at the University of Wisconsin-Madison and published in The Journal of Physiology that’s the focus of “Could this be a better solution to weight loss than calorie counting?” an article by Catharine Paddock PhD for Medical News Today. It suggests that the branch-chained amino acids (BCAA), long seen as being a great aid in recovery from intense exercise, may also do two other things.

Make you fat and give you type 2 diabetes.

Clearly it’s not that cut and dried, but Dudley Lamming, an assistant professor at the university who was a co-principal investigator, told Paddock “we’ve identified an unanticipated role for dietary BCAAs in the regulation of energy balance.” The research found that if you eliminate BCAAs from your diet and eat as much high-fat and high-sugar food as you want, you record a “dramatic improvement in metabolic health” through improvement in energy usage, glucose metabolism, and body-weight composition.

If you’re a pre-diabetic, obese mouse in a laboratory environment, that is.

Now I realize it’s necessary to use animals instead of humans for much food-based research, and that mice are especially well-suited for the task because of the genetic similarities they share with humans. I have no problem with that.

My problem is that I have trouble moving past the fact that something I believe is essential to quick recovery after tough workouts has any sort of a negative impact nutritionally — even on a pre-diabetic, obese mouse in a laboratory environment.

So I keep reading or researching until I have a better handle on the matter. When you find a study flying in the face of one of your successful practices or long-held beliefs, I suggest you do so, too.

For example, even the researchers of this study admit that prior research on BCAAs and insulin resistance — a harbinger of type 2 diabetes — does not align with theirs. In fact, they even acknowledge that their results may not translate to humans because of “species differences.”

So what are you to do in a situation like this? What Ronald Wilson Reagan, the 40th President of the United States, suggested we do during our rather rocky dealings over the reduction of nuclear weapons with the U.S.S.R.: “Trust, but verify.”

Reagan’s slogan is another way of saying what I’ve written many times before. That for you to achieve optimal health and fitness, you need to be both the researcher and the subject. The way you respond to the foods you eat and the workouts you do contains a variable not found in the scientific research performed at universities and published in journals.

You.

Which is why when the goal is optimal health and fitness, you need to be willing to consistently experiment on yourself.

And if you aren’t willing to do so ... then you need to keep really close tabs on this column.