Eating 30+ Different Plant Foods a Week for Gut Health: The Science Explained
When it comes to nourishing your gut, one of the most powerful tools isn’t a supplement or a complicated protocol — it’s variety in your diet. In fact, research from the American Gut Project found that people who include more than 30 different plant foods per week have a significantly more diverse gut microbiome than those who consume fewer than 10 (McDonald et al., 2018).
Why does this matter? A diverse gut microbiome is linked with:
Better digestion and reduced bloating
Stronger immune function
Lower levels of inflammation
Improved mood and mental wellbeing (via the gut-brain axis)
More efficient hormone metabolism and detoxification
The good news? Hitting this “30 plants per week” target is easier than you might think.
Why Aim for 30+ Different Plant Foods?
Each plant food contains its own unique mix of fibres, phytonutrients, and polyphenols. These compounds feed different species of beneficial gut bacteria. The broader your intake, the more “food” you provide for a wide variety of microbes — which translates to a stronger, more resilient gut ecosystem.
A healthy microbiome helps your body to:
Produce vitamins like B12, vitamin K2, and short-chain fatty acids (SCFAs), which fuel your intestinal cells (Ríos-Covián et al., 2016).
Support balanced immune activity, helping your body fight infection while reducing the risk of overactive inflammation (Belkaid & Hand, 2014).
Influence mood and cognitive health through the gut-brain connection (Cryan et al., 2019).
Assist with hormone metabolism, including the clearance of excess oestrogen (Plottel & Blaser, 2011).
What Counts as a “Plant Food”?
It’s not just fruits and vegetables! For this challenge, you can include:
Vegetables (all varieties count individually)
Fruits
Whole grains (e.g. oats, quinoa, brown rice, buckwheat)
Legumes (lentils, chickpeas, beans, peas)
Nuts & seeds
Herbs & spices
Seaweeds and plant-based oils
Tip: Each distinct plant counts once. For example, red and green capsicum = 1 plant (capsicum), but sweet potato and potato = 2 separate plants.
Example: 40 Plant Foods in a Week
Here’s how quickly the numbers can add up:
Vegetables (15): broccoli, zucchini, carrot, sweet potato, cauliflower, kale, spinach, red capsicum, beetroot, pumpkin, cabbage, onion, garlic, eggplant, mushrooms.
Fruits (8): apple, banana, blueberries, kiwi, orange, pear, strawberries, mango.
Legumes & Grains (6): brown rice, quinoa, oats, chickpeas, lentils, buckwheat.
Nuts & Seeds (5): almonds, walnuts, chia seeds, flaxseeds, pumpkin seeds.
Herbs & Spices (4): parsley, coriander, cumin, turmeric.
Bonus Plants (2): olive oil, nori (seaweed).
That’s 40 plants without much effort!
Easy Ways to Boost Your Plant Count
Mix up your grains: Rotate oats, quinoa, buckwheat, and rice.
Eat the rainbow: Add different coloured vegetables to each meal — purple cabbage, orange pumpkin, green kale.
Snack smart: A trail mix with nuts, seeds, and dried fruit can add 3–4 plants in one handful.
Get generous with herbs: Fresh parsley, basil, mint, or coriander not only count as plants but also add flavour and antioxidants.
Cook in batches: Curries, soups, and big salads are easy ways to pack 8–10 plants into a single meal.
Spice it up: Even a pinch of cinnamon, cumin, or turmeric counts toward your diversity score.
Final Thoughts
Incorporating 30 or more different plant foods each week isn’t about strict rules — it’s about expanding your variety. Start by rotating your regular staples, add in a few new foods, and keep an eye on your weekly count. Your gut microbiome will thrive with diversity, and the benefits extend far beyond digestion.
Small changes, like swapping your usual grain for a different one or adding an extra herb, can make a big difference over time. Remember: it’s not about perfection, but progress.
References
Belkaid Y, Hand TW. (2014). Role of the microbiota in immunity and inflammation. Cell, 157(1), 121–141.
Cryan JF, et al. (2019). The microbiota-gut-brain axis. Physiological Reviews, 99(4), 1877–2013.
McDonald D, et al. (2018). American Gut: an Open Platform for Citizen Science Microbiome Research. mSystems, 3(3).
Plottel CS, Blaser MJ. (2011). Microbiome and malignancy. Cell Host & Microbe, 10(4), 324–335.
Ríos-Covián D, et al. (2016). Intestinal short chain fatty acids and their link with diet and human health. Frontiers in Microbiology, 7, 185.