The Gut Effect

Alright guys, here we go...one of my favorite topics in nutrition! Today's topic, gut bacteria, is possible the coolest up and coming research in the field of nutrition and biochemistry right now. I am about to blow all of your minds (unless, of course, you already know all of this information, in which case this will be rather boring to you).

We have all heard since we were youngsters that every body is different. Everyone needs a different number of calories, has specific nutrient needs, has foods that they like and don't like, etc etc. But just how deep into our chemistry does this uniqueness go? Well, this question isn't entirely answerable just yet. All scientists have their speculations.

But what we do know is that the bacteria in every living human on this planet is different. There are 'bad' bacteria, like the flu virus, that is the same in every person and can be detected easily, but then there are the 'good' bacteria--the ones that don't make us sick and live in harmony with our body. Bacteria on our skin surface, in our blood stream, in our cells, and in our digestive system are unique to our bodies. 

As you can probably guess, I want to discuss a little bit about the gut microbiome, or bacteria, in this post. From the moment we are born, the only time of life when our guts are naturally sterile, our body begins to make the microbiome. The makeup of the gut microbiome is dependent on many factors: genetics, whether you were breastfed, what you eat, how much you exercise, environmental pollutants, the environment in which you were raised, and the environment in which you currently live. As you can see, many of these factors are constantly changing. Unless you eat the same thing everyday from birth to death, your gut microbiome is changing slightly everyday.

This explains the current trend of probiotics and prebiotics. Perhaps you have seen these advertised in the store? Items labeled as 'probiotic' means that the product contains the 'good' bacteria, while items labeled as 'prebiotic' means that the product contains food for the 'good' bacteria. Both are equally food for you. However, there are specifically 2 things to watch for when looking for a probiotics in particular:

1. If the product doesn't contain at least trillions of 'live cultures' (the most common way you will find 'bacteria' labeled on a container), it will do you no good and you are wasting your money.
2. If the product doesn't contain more than 3 or 4 different kinds of bacteria strains, the product will do you no good and you are wasting your money.

What makes our gut microbiome so unique and helpful is its sheer size and variety. Each bacteria has its own special role in the microbiome, and the more strains you have, and the higher number of each strain you have, the healthier your gut is. But what do the bacteria in the gut do? Well...this topic is still under a bit of debate, but I can provide some of the facts we for sure know. 

Scientists do know that the bacteria interact with the fiber we eat and assist with the 'fermentable' fibers. Basically, they eat the stuff our body cannot digest and turn it into energy for themselves. This is one of the many reasons why when we eat a lot of fiber, a nutrient the body cannot digest, we get a little...gassy. And typically that gas is smelly. This is your gut bacteria at work! As they make their food and energy from the stuff we cannot digest, gases are released as a byproduct of this process. 

Because of this, scientists have found out something that I think is pretty amazing: bacteria can contribute up to 15% more calories to someone's day. As in, two people can eat the same foods in exactly equal quantities, but each person will absorb different amounts of calories. There are certain bacteria strains that are better at harvesting energy than others, meaning that the amount of calories we eat is not accurate to the amount that is absorbed. 

The implications of this are pretty astounding. As you all can probably guess, scientists are finding that obese individuals have the strains of bacteria in their gut that are more efficient at harvesting energy than those that aren't. Therefore, up to 15% of the calories that obese individuals are eating are calories that they have no control over. And if you are eating a 2,000 calorie diet, 15% can be an extra 300 calories per day. If that person's intake is consistent, and the bacteria are consistent energy harvesters, then the person can gain weight quickly without even meaning to. 

This all comes back to genetics: though we can change our gut microbiome through many factors, some people are more genetically inclined to have energy harvesting bacteria in their guts and therefore, do not have much choice or control over the matter. However, as individuals make healthy lifestyles their goal, they can prevent what they can and change what bacteria they can. In general, obese individuals do not have as much bacteria, and their variety is poor. And as we discussed before, the more bacteria the merrier! It's just like our diets. The more variety in our diet, the easier it is to make sure we are getting all of the nutrients we need. The less varied our diet is, the easier it is to experience nutrient deficiencies. 

Someone once described the gut microbiome as a rain forest: there is a lot of life, a lot of variety, and a lot going on. On the other hand, the microbiome of an obese or otherwise unhealthy individual is more like a desert: there is still a lot going on, but only a small amount of life is adapted to such an environment. I just think it's so cool that we continue to see the pattern of variety down to the individual cells in our body. Nature is a master at patterns, and this one is no different!!!