Feed your belly (yep... thats right)...

There is a lot we dont yet understand about gut health and how to ‘optimise’ it. There is one thing science does know however. It can be changed - very quickly - by what you eat.

So what is the right food for gut microbiome?

‘Feeding your belly’ might not sound like the most obvious thing, but, in the quest to provide the best conditions to grow and feed your baby (if you’re breastfeeding) optimising your own gut health is extremely high up on the agenda (click here to be reminded why).

We know that the use of store bought Probiotics as a ‘shortcut’ to gut health is perhaps not as easy or effective as you may think (click here for full info article). They have shown some success when very targeted and administered in a clinical setting, but, the over the counter type that are heavily pushed on us these days as the marketing machines have latched on to the latest ‘health craze’ are probably at this stage not worth spending your money on.

So what else can we do? Well, this is where feeding your belly comes in…


It turns out - what we eat is very effective at influencing our own gut microbiome. In fact, studies have shown that the population of your gut bacteria can be changed as quickly as 24 hours by altering what you eat.

‘Switching from a low-fat, plant polysaccharide-rich diet to a high-fat/high-sugar “Western” diet shifted the structure of the microbiota within a single day, changed the representation of metabolic pathways in the microbiome, and altered microbiome gene expression…..colonization history influences the initial structure of the microbial community, but that these effects can be rapidly altered by diet.’ (1)

‘An acute change in diet—for instance to one that is strictly animal-based or plant-based—alters microbial composition within just 24 h of initiation, with reversion to baseline within 48 h of diet discontinuation’ (2)

How powerful can this be for your baby?

Well, we know that one of the best way for a baby to develop the foundations for good immunity, health and neuro functionality is developing its own microbiota (you want balanced levels and diversity) which is initially dictated by what is picked up from the mother’s own microbiome (in utero plus skin/birth canal and breastmilk). That is the foundation - but from that point onwards your environment matters and can shape the makeup of your gut. In fact a study looking at twins showed that even identical twins had different microbiota compositions (3)

So - what is the best way to ‘feed your belly’ ?

Well first and foremost in big picture terms it is relatively obvious. A ‘Western Diet’ is not good for the health of our guts. What is a ‘Western Diet?’ Well in simple terms: high fat (especially animal), high sugar and low fibre:

‘the configuration of the microbiota, its microbiome and meta-transcriptome change in a rapid, dramatic and reproducible fashion after switching from a plant polysaccharide-rich/low fat diet to a high-fat/high-sugar Western diet’ (4)

This is of course pretty obvious, however, digging in to the detail….


What are the ‘pitfalls’ and what are the ‘heroes’ of the gut health food world?  

The Mediterranean diet has been cited by many as the ‘poster child’ for good health. Why? Well - its mix of all the ‘good things’. Its not about avoiding one food group or focusing heavily on another; its about finding the best types of the particular group and balancing these along with the others. Diversity of what you eat is key and elimination of entire food groups (unless you have an intolerance) won't help with that. So here is a break down of why the Mediterranean diet satisfies most of the key criteria for ‘feeding your belly’:

The ‘right’ fatty acids:

The Mediterranean diet is excellent when it comes to the optimal fatty acid profile as it generally contains both monounsaturated and polyunsaturated fatty acids (Olive Oil being the prime example here).

As we know Saturated Fat is less ideal. Animal (meat) is usually a source for this and as we know the Mediterranean diet limits meat (it's usually used for a celebration or occasion rather than every day) and instead uses more fish. We also know that processed foods are usually high in these types of fat.

‘These results indicate that gut microbiota may promote metabolic inflammation...upon challenge with a diet rich in saturated lipids’ (5)

The ‘right’ proteins:

Once again, it's about finding the right source. We know that the Mediterranean diet generally consists of more vegetable than animal protein, including nuts and fish. Interestingly clinical studies have shown that when you concentrate your protein intake from plant sources you tend to have a more positive effect on the diversity of your gut bacteria than when you focus on animal/red meat sources:

‘A majority of the studies noted that protein consumption positively correlates with overall microbial diversity. For example, consumption of whey and pea protein extract has been reported to increase gut-commensal Bifidobacterium and Lactobacillus, while whey additionally decreases the pathogenic Bacteroides fragilis and Clostridium perfringens. Pea protein has also been observed to increase intestinal SCFA levels, which are considered anti-inflammatory and important for maintenance of the mucosal barrier (6)

The pitfall here is really a diet high in red or processed meat - not what you want….

Once again, we also know that pesticides and antibiotics will have a negative effect on our microbiome so its better to eat less of better (wild or organic) quality. Save your bullets.

The ‘right’ Carbs:

No carbs before Marbs? Not sure about that…

Once again it depends on which ones you choose. High fiber and low glycemic index are the ones you want.

The major hero in fact is fiber/non-digestible carbs here. Why? This is a natural source of ‘prebiotic’. What is a prebiotic? (Click here for a link to the profile here) Think of it as food for the bacteria you do have. This type of fibre which we ourselves cant process provide great food and fuel for our microbes. The hidden hero of the gut world…

How does this work? Well, this type of fibre doesn’t get broken down by the small intestine, it goes through to the large intestine where it is effectively fermented by the host microorganisms. These are generally known as “microbiota accessible carbohydrates” (MACs).

Where can you find these?

Soybeans

Non-Digestible Oligosaccharides: which naturally occur in onions, banana, garlic and Jerusalem Artichoke, legumes.

Inulins (type of soluble fibre found in many plants): found in Asparagus, Chicory Root, Garlic, Artichoke and Onions.

Unrefined wheat and barley, raw oats

‘A diet that is low in these substances has been shown to reduce total bacterial abundance. On the other hand, high intake of these carbohydrates in 49 obese subjects resulted in an increase in microbiota gene richness.’ (7)

The pitfalls:

The quest to be slim has seen a massive growth in artificial sweeteners - we are talking here about saccharin, sucralose, aspartame. You may have heard some of the controversy such as the view that they actually promote issues with glucose intolerance - even worse than pure glucose. It appears, that this is related to their effect on the gut - specifically by altering the gut microbiota. Studies conducted in mice showed significant intestinal dysbiosis (ie. imbalance in the gut bacteria). Steer well clear from these.

We also know that high sugar diets (high fructose in particular) in general aren’t ideal. They have been commonly associated with over growth of a type of yeast Candida for one thing.  

Dairy:

Now, not everyone can tolerate this and it is always important to listen to your body. It is also important for anyone to consume diary that is organic and unsweetened wherever possible to avoid hormonal disruptions. Several studies have shown increased total bacterial load after regular consumption of fermented milk or yogurt. Kefir has been shown to be particularly good. On that note….

Fermented Foods:

Most of us now know that fermented foods are the heroes of the gut world. Think Sauerkraut, pickles, Kombucha and Kimchi. All you really need to know about these is that they are super rich in probiotics which grow during the fermentation process.

Kombucha is basically black or green tea and sugar (in its simplest form) but it contains a colony of bacteria and yeast which (when combined with sugar) starts the fermentation process. A word of warning here - Kombucha can contain trace amounts of alcohol so worth being aware of that if you are pregnant or breastfeeding.

Sauerkraut is made from cabbage. Ideally you make your own which is very easy to do but if you want to buy make sure you look at the label as the stuff you can buy isnt always fermented, I would avoid the canned variety and look for the type that is refrigerated. Also a great source of fibre.

Pickles: these are literally cucumbers in salt water. Once again super easy to make yourself and once again if you’re buying rather than making, ensure they are organic and fermented.

Kimchi: a Korean favourite made from various vegetables usually alongside a seasoning.

If you’re pregnant however one fermented food that you should avoid is unpasteurised milk which may be fermented but is risky (becuase of potential unwanted bacteria). Just steer clear - miso soup is one good safe option.

Bone Broth?

This has become a bit of a health food craze of late, however, the science behind it isn't quite as compelling for now. Instead a meat stock might be the better way to go (click here to learn more).

Bottom line: once again it's not rocket science. It is not about going to extremes but about being smart and as balanced as possible with as many unprocessed, whole foods as possible. The one thing that is really important thing to take away from this is simply how important what you eat actually is, particularly when it comes to building a healthy gut microbiome.

Footnotes:

  1. TURNBAUGH PJ, RIDAURA VK, GORDON JI: The Effect of Diet on the Human Gut Microbiome: A Metagenomic Analysis in Humanized Gnotobiotic Mice: Science Translational Medicine. 2009. Nov 11: 1(6)

  2. SINGH R, CHANG H-W, LIAO W: Influence of diet on the gut microbiome and implications for human health: Journal of Translational Medicine. 2017. 15:73

  3. TURNBAUGH PJ, RIDAURA VK, GORDON JI: The Effect of Diet on the Human Gut Microbiome: A Metagenomic Analysis in Humanized Gnotobiotic Mice: Science Translational Medicine. 2009. Nov 11: 1(6)

  4. TURNBAUGH PJ, RIDAURA VK, GORDON JI: The Effect of Diet on the Human Gut Microbiome: A Metagenomic Analysis in Humanized Gnotobiotic Mice: Science Translational Medicine. 2009. Nov 11: 1(6)

  5. SINGH R, CHANG H-W, LIAO W: Influence of diet on the gut microbiome and implications for human health: Journal of Translational Medicine. 2017. 15:73

  6. SINGH R, CHANG H-W, LIAO W: Influence of diet on the gut microbiome and implications for human health: Journal of Translational Medicine. 2017. 15:73

  7. SINGH R, CHANG H-W, LIAO W: Influence of diet on the gut microbiome and implications for human health: Journal of Translational Medicine. 2017. 15:73

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This article is for informational purposes only. This article is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment and should never be relied upon for specific medical advice. The information on this website has been developed following years of personal research and from referenced and sourced medical research. Before making any changes we strongly recommend you consult a healthcare professional before you begin.