I’ll freely admit it: I’m skeptical of most internet wellness trends. Long before I binge-watched Apple Cider Vinegar on Netflix, I muttered phrases like, “Dose matters,” and “Arsenic is natural too” when reading the comments section. So, when I first heard about the “30 plants a week” challenge, I quickly dismissed the idea. But then I looked into it—and to my surprise, there’s some genuinely solid science behind it.

Let me be clear: I’m not a scientist so my ability to fully interpret complex research is limited. But if you’re curious about your gut health, here’s a digestible (pun intended) and very simplistic summary of the science that underpins this way of eating.

Where Does the Science Come From?

The 30-plants-a-week idea originates from the American Gut Project, one of the largest studies ever conducted on the human microbiome. Researchers analysed the gut bacteria of over 10,000 people across the globe.

Their key finding? People who ate 30 or more different plant foods per week had much more diverse gut microbiomes than those who ate 10 or fewer.

That’s they key takeaway: Want more gut biodiversity? Feed your microbes a variety of plant based foods..

Why Gut Microbiome Diversity Matters

Your gut is made up of trillions of microorganisms. While they play a key role in digesting food, research increasingly shows that these microbes also influence immune responses, your metabolism and are even connected to your mental health.

Gut Health & Immunity

Scientists believe that a balanced, diverse microbiome helps to train immune cells to tell the difference between harmful pathogens and beneficial bacteria – you can almost think of your gut as a school for your immune system.

There is also data demonstrating that an imbalanced gut microbiome (a condition called dysbiosis) can trigger inflammation, resulting in higher incidence of allergies, autoimmune disorders and greater risk of infection.

A few compelling studies back this up:

• A Cell study showed that diets high in fibre and fermented foods can boost immune function.
• Research from Harvard Medical School found that certain gut bacteria produce anti-inflammatory molecules, potentially protecting against conditions like colitis.

Metabolism & Gut Health

Research is showing that the health of your gut microbiome can have a big impact on your metabolism. Some types of gut bacteria have been shown to help control blood sugar levels, influence how your body stores fat, and even affect the hormones that tell you when you’re hungry or full. In a 2013 study published in Nature, scientists found that when gut microbes from lean people were transplanted into mice, the mice actually gained less body fat. While researchers are still figuring out exactly how this all works, there’s a clear connection between an unhealthy gut/dysbiosis and conditions like obesity, type 2 diabetes, and metabolic syndrome. We can’t say for sure that gut issues cause these problems, but the link is definitely strong.

The Gut-Brain Axis

Your gut and brain engage in two-way communication system called the gut-brain axis. Scientists have linked imbalanced gut microbiomes to a range of conditions including:

• Anxiety
• Depression
• Mood disorders

According to a 2020 review in ScienceDirect, changing your microbiome can actually influence brain function and behaviour. Another study from MDPI described how specific bacteria help produce neurotransmitters like serotonin, which play a big role in mood regulation.

So yes—feeding your gut bugs better food may help you feel better emotionally, too.

Resources

For the non scientists amongst us, I highly recommend Dr Erica Ebbed Angle’s Ted Talk which was easy to follow and pitched at the right level for me. I’ve just started reading “The Good Gut” by Justin and Erica Sonnenburg and will report back with my thoughts in a future post (I’m trying to read more and stream less so hopefully I get through this one quite quickly).

A few other resources that I’ve used to answer my own questions over the last few months are:

Harvard Health Blog – Microbiome Section

• https://www.health.harvard.edu
• Trusted, evidence-based articles on gut health and related topics.

The American Gut Project

• https://microbio.me/americangut
• Citizen science project with resources to learn about your own microbiome and compare it with others.

See you next time for some practical tips on getting started on your 30 Plant journey!