Liz's Blog for a Healthier, Happier Life

The Healthy Gut Challenge: 30 Plant Foods in 7 Days

Eating 30 different plant foods in 7 days is easier than you think

I have an exciting, health-protective, dietary challenge for you.  It involves the trillions of microbes that live along your gastrointestinal tract.  It’s based on the largest microbiome study to-date, the American Gut Project – a research project designed to determine how many types of bacteria live in our bodies, and how our diet and lifestyle affects these microbes.  Preliminary results from this ongoing study have found that a more diverse plant-based diet makes for a more bacterially diverse gut. Specifically, people who consume more than 30 different plant foods (different types of fruits, vegetables, whole grains, legumes, nuts and seeds) each week have much more diverse gut microbiomes than those who consume 10 or fewer different plant foods weekly. 

Why Diversity Matters

A more diverse microbiome results in a more stable and resilient microbial community that is better equipped to powerfully protect your health.  This includes lowering your risk of colon cancer, inflammatory bowel disease, celiac disease, heart disease, diabetes, arthritis, obesity, allergies, depression, and more.  A healthier gut microbiome means a healthier, happier you!

The Challenge:  Eat 30 Different Plant Foods in 7 days

Eating 30 different plant foods in one week may sound overwhelming, but with a little planning, it’s much easier than you may realize.  Here are my top tips to help you on your way:

1.  Choose a start date for your 7-day challenge – perhaps today, tomorrow, or after your next major trip to the grocery store.

2. Commit to keeping track each time you consume a new or different plant food over the course of 7 days.  Write the food item down on a notepad or keep an ongoing, updated list on your phone. 

3. Going full vegan or vegetarian for 7 days is definitely not required – just make sure you include a variety of plant foods at each meal and at snack times.   

4.  Look for ways to add more plant-food variety to each meal.  For example, at breakfast I top my super, high-fibre cereal with a few tablespoons of ground flaxseeds and at least three different kinds of berries (some combination of blueberries, blackberries, raspberries, and strawberries). It all adds up.

5.   Main course salads, for lunch or dinner, are a fantastic way to consume lots of different plant foods.  Add a mix of veggies to your salad (dark leafy greens, carrots, peppers, tomatoes, cucumbers, etc.).  Consider also adding some nuts or seeds, fresh fruit (like berries, mandarin oranges, or kiwi), whole grains (like cooked quinoa or brown rice) or beans (like chickpeas).  Stir-fries or other veggie-loaded meals are also highly recommended.

6.  A handful of nuts makes an awesome snack.  Instead of having just one type of nut, enjoy mixed nuts or a trail mix that contains nuts, seeds and dried fruit. 

7.   Be generous with your use of herbs and spices in all your cooking and meals.  Add fresh herbs, like basil, to your salads.  I regularly use a spice blend that contains six different spices (it’s called “Herbes De Provence”) when roasting or sautéing many different types of vegetables.  I also add cinnamon sticks, whole cloves, and freshly, sliced ginger root to my big pot of green tea each morning (and yes, both coffee and tea come from plants and should be included in your weekly tally!).

8. When it comes to grains products (like cereals, pasta, breads, or crackers), look for products that are “multi-grain” and contain added seeds. Just be sure that all grains listed (rye, wheat, oats, barley, etc.) are 100% whole grain.  Many multi-grain products contain a significant amount of white flour (listed as wheat flour on the ingredient list).  You don’t want that.     

Closing Thoughts

Consuming a diverse, plant-based diet is an important way to keep your gut microbiome in tip top shape.  By keeping track of what you eat, you can learn what’s required to meet the recommended weekly goal of consuming 30 different plant foods each week. 

P.S.  Eating a high-fibre diet is also super critical for a healthy gut microbiome.  I’ll talk more about this in another post.  In the meantime, please share this 7-day challenge with family and friends. Report back and let me know how well you did and what you learned.  Good luck and have fun! 


Cryan, J., et al.  “The Microbiota-Gut-Brain Axis.” Physiol Rev. 2019 Oct 1;99(4):1877-2013.

Heiman, M. and Greenway, F.  “A healthy gastrointestinal microbiome is dependent on dietary diversity.” Mol Metab. 2016 May; 5(5): 317–320.

Johnson, A., et al. “Daily sampling reveals personalized diet-microbiome associations in humans.”  Cell Host Microbe. 2019; 25(6):789-802.

McDonald, D., et al. “American Gut: an Open Platform for Citizen Science Microbiome Research.” 2018 May 15;3(3).

Valdes, A., et al.“Role of the gut microbiota in nutrition and health.” BMJ. 2018 Jun 13;361:k2179.



I’m a registered dietitian with a passion for peanut butter sandwiches and an undying love for chocolate. I’ve been researching, writing, and speaking about eating for optimal health for over 25 years. I have two wonderful daughters, love hiking year-round, and playing hockey in the winter. Perhaps, most importantly, I never let a good dance song go to waste!

Post a Comment:

Subscribe to Liz’s blog for a healthier, happier, & more delicious life!

(P.S. Your email will never be shared!)