The proof really is in the pudding — especially if the pudding is part of the poo that plops into the toilet.

This potentially offensive image is not designed to draw your ire as much as your attention to the following fact: Analyzing fecal matter is a worthwhile medical endeavor. It not only helps in assessing your personal health, but it also may very well provide the overall information needed to end the obesity epidemic.

For years, researchers knew that the presence of certain gut bacteria made it more likely for your body to store fat and that other gut bacteria made that less likely to happen. Unfortunately, around 100 trillion bacteria exist in your gut. Primarily because of that mind-boggling fact, researchers could not be sure to what degree genetics and environmental factors like diet influenced whether or not your gut became a breeding ground for the former or the latter.

To a much greater degree, now they do. And the knowledge they accrued came from — you guessed it — gathering poo.

Researchers from King’s College London in the United Kingdom and lead by their colleague Cristina Menni procured fecal samples from more than 1000 twins, about 95 percent of whom were females. Analyzing the samples for 1,116 metabolites that could be linked to different types of gut bacteria led the researchers to determine that 17.9 percent of gut processes are affected by genetic factors while 67.7 percent of them are influenced by environmental factors — especially diet.

Professor Tim Spector, the head of King’s College London’s Twin Research GroupEnd and co-author of the paper that contained the study’s results published in the journal Nature Genetics earlier this year, called the research “great news.” You should too since it shows something you control, the foods you choose to eat, is a greater ally — or a bigger enemy — than something you do not, genetics, in the battle of the bulge.

Similarly, research published last year in Cell Reports reinforces the food-trumps-genetics belief when it comes to gut bacteria affecting the success or failure of your diet.

In this study, researchers used magnetic resonance spectroscopy on urine samples from about 50 genetically similar lab mice to assess what was going on in their guts. In other words, they viewed the molecules in the samples to establish how the gut bacteria in each was functioning. They then switched the mice from standard mice food to a high-fat diet.

As expected, the mice gained weight.

What was not expected were the varying amounts of weight gained. Only genetically similar mice were used, and the calorie intake and activity levels for all remained constant, so why did statistically significant differences in the amount of weight gained occur?

The paper posits that the unique composition of gut microbes in the supposedly similar mice caused them to process the same high-fat diet differently.

The co-senior author of the study, professor Jeremy K.Nicholson from Imperial College London, told Medical News Today that the study shows the “power” of the tens of trillions of microbes in your stomach “to influence” your health and that the end result of your diet is determined “not only by your genes, but also the genes of your gut microbes.”

And the subsequent study that analyzed the fecal matter of twins clearly shows that the make up of your gut bacteria results in large part from the foods you choose to eat.

So what foods should you eat to allow the good bacteria in your gut to thrive and the bad to decline? Research hasn’t provided any definitive answers yet, but it has shown that processed foods in general seem to unfavorably alter gut bacteria.

The emulsifiers used to improve food texture and extend shelf life in processed foods, for instance, have been found to reduce the bacterial diversity in the digestive tracts of laboratory mice.

But bacterial diversity is good — or at least natural. The Yanomami tribesmen of the Amazon rainforest, for instance, have 50 percent more bacterial diversity in their stomachs than typical Americans.

To encourage bacterial diversity in your gut, eat fermented foods — like traditional yogurt and sourdough bread, sauerkraut, pickles and other vegetables pickled in brine, miso, soy sauce, and sour cream — and increase your intake of dietary fiber. Eliminate as much processed foods as practically possible, but don’t feel as if you have to replace them with foods advertised to promote the growth of good gut bacteria, prebiotics, or foods or supplements with probiotics, the good gut bacteria itself.

Just eat the standard healthy stuff, such as fresh fruits and vegetables, foods featuring whole grains, low-fat or no-fat dairy products, fish, fowl, and lean cuts of red meats. Provided they’re prepared in a healthy manner, they should create the type of environment in your gut that keeps you healthy — and from getting heavy.