Did you know that there are more bacterial cells on and in you than there are, well, human cells? They’re quite literally everywhere: on our skin, in our mouths, lungs, in the harsh acidic environment of our stomachs and, rather importantly, in our gastrointestinal tract.

Researchers estimate that between 10 and 100 trillion bacterial cells inhabit our GI tract. So, you’d think it’d be important to know a little bit about them and what they do, right?


Functions of our bacterial cells

They have quite a long list of things they do for us. Which is why taking good care of them is pretty important.

Our bacterial cells:

  • Assist us in digesting and absorbing nutrients
  • Feed on the starch in our food (resistant starch) to produce health promoting short-chain fatty acids
  • Prevent bad bacteria from getting a foothold
  • Metabolise (process) medications, phytonutrients and hormones
  • Produce polyamines which affect cell growth

And that’s just some of their functions. Our microbiome has intimate ties to our immune system: when our gut health is out of whack so too is our immune system.

So, you might want to think twice before taking another round of antibiotics unless it’s absolutely necessary. Sure, antibiotics help you kill off whatever pathogen your body is fighting but they also kill off a substantial swath of commensal (friendly) bacteria.

For example, evidence has suggested that babies who are treated with many rounds of antibiotics later go on to develop asthma. Compromised gut bacteria is also associated with other inflammatory conditions such as eczema.

Disrupted gut bacteria has been linked to obesity and metabolic dysfunction.

For example, research has shown that obese people tend to have reduced bacterial and fungal biodiversity. They also seem to have a higher proportion of Firmicute and fewer Bacteroidetes. Interestingly, the reverse is true for lean people.

Having certain types of fungi such as Sacharomycetes, Tremellomycetes and Cystobasidiomycetes is linked to greater adiposity (fat) and metabolic conditions such as dyslipidemia (high levels of circulating fat), insulin resistance, high blood pressure and inflammation.
In contrast to this, as you might expect, having other types of fungi such as Agaricomycetes and Eurotiomycetes seem to offer protection against these conditions.

Interestingly, even if lean and obese people eat the same food, the bacteria and fungi of the obese people may actually harvest more energy from it. Another reason to treat calories in versus calories out with caution. While you can’t argue with the rules of energy balance, you just simply cannot account for all the variables in that equation!

So, what happens when your microbiome is out of balance?

Bearing in mind all of the functions of our intestinal bacteria, it’s little wonder there’s such a broad range of symptoms associated with GI bacterial disruption.

These include, but are not limited to:

  • Mood disorders (including both anxiety and depression)
  • Overgrowth of pathogens and other harmful bacteria
  • Lowered immunity, frequent colds and flu
  • Poor digestion, absorption and gut motility (diarrhoea/constipation)
  • Poor clearance of medications and hormones

What can you do?

Research has demonstrated that supplementing with probiotics (live cultured bacteria) can reduce or alleviate many GI problems. It can even help with other inflammatory conditions which are seemingly unrelated to your gut health such as acne.
It appears that the best probiotics to take are multi-strain, broad spectrum probiotics with a high CFU number (colony forming units).
Here’s one I personally use.

Cultured foods
Sourdough breads, yoghurt, kimchi, cultured cottage cheese and, my personal favourite, kefir are all examples of fermented foods which can help boost the diversity and health of your microbiome.

Clients of mine suffering with IBS and GERD (gastroesophageal reflux disease or, more commonly, chronic heartburn) have experienced positive results from taking a daily dose of probiotics and kefir. It won’t cure everyone but it’s certainly worth a try.

Don’t overdo it on the kefir though. Too much of it and you could find yourself dashing for the toilet. 200ml should be plenty.

Vegetables. Surprise surprise

Needless to say that vegetables are absolutely crucial to our gut health. Vegetables contain many health promoting compounds such as vitamins, minerals, phytonutrients (beneficial compounds specific to plants) and fibre which, as we all know, keeps us regular. But there’s a specific type of fibre known as resistant starch which our gut bacteria feed on. Be sure you’re eating enough raw and cooked vegetables to keep you colon dwelling critters happy, relaxed and content.

Quick tip: Cooking and subsequently cooling potatoes results in what’s know as starch retrogradation. This occurs when the starch granules in cooked potato reorganise themselves to form a more crystalline structure. This retrograded starch is less digestible and so behaves just like resistant starch.

So, if you’re concerned about feeding your gut bacteria but you’re not ready to begin piling up the plate with vegetables just yet, cook, cool and (gradually) eat a bag of spuds. Now you’ve got some resistant starch to hand for a few days at least. Lucky devil.