What you’ll read next is certainly not original. It’s just true and missing two expected modifiers.

For every action there is a reaction.

Despite their inclusion in the common saying that doubles as Sir Issac Newton’s third law of motion, “equal” and “opposite” have been deleted today because this article’s not about the conservation of momentum. It’s about health and fitness and how your pursuit of it sometimes defies not only physics but also basic math.

If you’ve ever attempted to lose a specific amount of weight by reducing the number of calories you consume and/or increasing the number you burn, you know that. Even the simplest number crunching during a diet can’t be trusted.

There are several reasons for this.

One is that your basal metabolic rate — how much energy you burn at rest — is determined by more than how much muscle and fat you possess and how much energy is required to digest your foods’ macronutrients. Dieting itself lowers your BMR, even if you’re eating mostly the macros that require the most energy to burn, protein and complex carbohydrates.

Moreover, the more weight you lose, the lower your BMR goes. In addition, weight loss also affects the secretion of certain hormones that determine whether fat gets stored or burned.

So what seems to be a matter of simple subtraction simply doesn’t work. You take away two from six, so to speak, only to find the answer is not four but five.

But only if you’re lucky. If not, the answer’s six.

And if you’re really unlucky (aka genetically cursed), you do the same subtraction problem months later and find it’s somehow become an addition problem — and a real problem at that. Because the new answer’s eight.

All this exemplifies why today’s article begins with such a seemingly obvious and unoriginal statement, yet one that merits restatement.

For it may not be equal. It may not be opposite. But every action creates some sort of a reaction that adds or subtracts from your health and fitness.

These additions and subtractions can be so minuscule that you miss them, but they do indeed exist and this much is true. They reside in the same place some find God.

In the details.

Which is why I write about them, especially the ones you might overlook. Like the potential link between colorectal cancer and a diet many people find the quickest way to lose weight: the low-carb diet.

The science world has long maintained the dietary choices you make either increase or decrease your risk of colorectal cancer, a cancer that’s been making news for another reason. Once seen as a cancer afflicting people aged 50 and over, its incidence has increased in children, teens, young adults — and markedly so in those in their early 30s.

In a 21-year span starting in 1999, for instance, the incidence of colorectal cancer increased 71 percent in those between the ages of 30 and 34.

So researchers at the University of Toronto decided to feed mice one of three diets along with three specific types of bacterial strains linked to the sort of DNA damage and inflammation that can lead to colorectal cancer. They did so for 16 weeks and presumably because of something else making news as of late: the connection between a healthy gut and overall good health.

One of the bacterium used in the experiment you know, but not by its full name. Escherichia coli is almost always referred to as E. coli and is notorious because some strains cause severe food poisoning.

When that occurs because thousands of people have consumed mass-produced processed food gone bad, it becomes big news. And in this study, E. coli created big news, too.

Out of all the combinations of diets and bacteria fed to the mice, the only one that lead to a higher number of polyps and tumors in the colon and the rectum was the low-carb and E. coli combo. Big news because about 60 percent of the time that colorectal cancer occurs in humans, high amounts of E. coli are found as well.

What’s nearly as noteworthy is that this study serves as a fine example of how every action creates a reaction, albeit in this case it’s an unexpected one.

Another unexpected reaction in the study occurred when E. coli was added to the diet generally regarded as unhealthy due to the prevalence of ultraprocessed foods in it, the Western diet. No significant increase in polyps and tumors was detected.

Yet the most significant takeaway from this study may be the confirmation of the good ingesting dietary fiber does. For whether the diet was low carb or Western, adding fiber to each reduced tumor formation and the inflammation associated with adding harmful strains of bacteria into the gut.