Prebiotics + Probiotics = Synbiotics
A simple equation for acheiving a happy, healthy gut.

Prebiotics = Food for probiotics

So what do probiotics – “good bacteria” – eat? Prebiotics is the simple answer that’s being used on product packaging and in the news. But what are prebiotics?

Prebiotics are chains of sugars (or carbohydrates) that we humans are incapable of digesting. These carbohydrate chains, often referred to as “fibers”, come from plant sources, including certain types of fruits and vegetables. Prebiotics include: carbohydrates, such as mucins, that are excreted in the guts of humans and other animals; chondroitins, which makes up animal connective tissues; and, chitin, which provides a shell for bugs, crabs or lobsters. Basically, anything that is a long string of sugars (or polysaccharides if you’re playing Scrabble) is a prebiotic.

So why do we need prebiotics? We need them because probiotics need them to do their job. Prebiotics perform a necessary preliminary function that helps probiotic gut bugs break the linkages between the sugars in prebiotics and turns the long indigestible chains into simple sugars that our bodies can use;

Probiotics and prebiotics work together to keep our guts health.  It’s sort of a symbiotic relationship: each one benefits from the other and neither is as effective alone. It makes sense, then, why scientists call products that contain both pro- and pre- biotics “synbiotics” – a happy marriage between good gut bugs and polysaccharides.

Not all fibers are created equal: the more complex the better

While many people have heard of prebiotics, few really understand how they work. It’s important to be aware of the differences between prebiotic fibers and to look for ones that are complex. Some fibers are derived from common sugars (like glucose, sucrose or fructose) and contain simple linkages between sugars. These are often referred to as cellulose (or starch), inulin, and fructooligosaccharides or FOS, and are all common ingredients in today’s health products. Other fibers, made up of unconventional sugars (like glucosamine, arabinose, mannose, or fucose) and joined by uncommon links to form long polysaccharide chains, are more complex.

This second group of fibers is more complex than the first, and from a gut health standpoint – the more complex the better! Complex fibers make your gut bugs happy because they require more varieties of bugs to do the work in breaking down the fiber. In other words, a greater number of gut bug species are able to feed off of complex fibers, which thus allows a greater number of beneficial bacteria to live and colonize in the gut.

In 2005, the Nobel Prize in Medicine was jointly awarded to Barry J. Marshall and J. Robin Warren for their discovery of a gut bug’s role in disease. The “prize winning” bacterium was Helicobacter pylori and the associated disease was stomach ulcer, more specifically, duodenal ulcers (for those googling picture of the intestine right now, the pylorus is the junction between the stomach and the duodenum and small intestine).

So the “Germ Theory of Disease” that was postulated 450 years ago, and scientifically proven by Louis Pasteur only 150 years ago, has now taken a turn to look at the “gut” and the specific bacteria living there. And since the 1970’s and 1980’s, when the 2005 Nobel laureates got their start, there have been an ever-increasing number of scientists looking at the microorganisms living in the gut and exploring their potential roles in disease and health.

What I find interesting about today's gut bug discussion is that many scientists are suggesting that it’s not always just an issue of good bacteria, but also a matter of balance – balancing the good with the bad. I say this because it is suggested that most intestines harbor as much as 15% bad bacteria. Thus, in order to be healthy, we must maintain enough good bacteria to keep the bad bacteria from gaining the upper hand or from moving to a new location in the GI tract (where they aren’t supposed to colonize).

The best way to maintain an optimal balance of good and bad bacteria is to:

1. Give the good bacteria the things they need to survive; they can’t do it alone!
   Probiotics are delicate and can die off very easily. By giving them the right food (prebiotics) and a hospitable natural environment, that they can multiply and colonize.
2. Avoid things that give the bad bacteria an upper hand.
   In the coming months I will talk about the various environmental factors, common in the Western world, that help give bad bacteria a fighting chance.