Thirty plants in seven days sounds like an enormous salad. Don't worry, it's actually a lot easier than you might think.
Oats count. So do chickpeas, walnuts, cinnamon, frozen berries, canned tomatoes, and the cilantro scattered over dinner. Once "plants" stops meaning "fresh vegetables," the number gets much easier to reach.
The idea comes from the American Gut Project, a large citizen-science study. In the comparison behind the famous 30-plant finding, 41 people who reported eating more than 30 plant types a week had a different gut microbial profile than 44 people who ate 10 or fewer, including more of several bacteria associated with fermenting plant material.
Those groups were a small subset of the larger project. The study was observational and relied on self-reported diets. It did not prove that 30 is a biological cutoff, a prescription, or a cause of better health.
How to count 30 different plants in one week
The American Gut study did not establish a detailed point-scoring system. For this shopping challenge, use a simple convention: count each distinct plant food once per week, regardless of form. Oats are one plant whether you eat them once or every morning. Under this convention, red and green apples count together as one.
These easy rules keep the challenge useful:
- Frozen, canned, and dried plants count.
- Whole grains, beans, lentils, nuts, seeds, herbs, and spices count.
- Plant-based fermented foods count as the plant they came from. Sauerkraut is cabbage; tempeh is soy
The American Gut study did not establish a minimum serving that makes a plant count. The point is variety, not gaming the total with a dusting of 30 ingredients.
If you currently eat 8 to 10 plants a week, you don't need to jump to 30 tomorrow. Add a few more to meals you already make. A sudden increase in fiber can bring gas or bloating, so a slower climb may feel better.
Produce can contribute 10 to 12 plants
Produce is the easiest place to make a large dent in the total. Aim for 10 to 12 plants across fruit and vegetables, using what you already like as the base.
Color is a handy shopping prompt, though it isn't a scoring system. A cart with berries, apples, leafy greens, carrots, peppers, tomatoes, onions, and broccoli gets you farther than buying five versions of the same salad.
Mixed frozen berries, slaw mix, and frozen vegetable blends can add several plants without leaving a refrigerator full of produce that spoils before Friday.
Freshness doesn't decide whether a plant counts. Frozen spinach is still spinach. Canned tomatoes are still tomatoes. The format that you will actually cook is usually the useful one.
Download the printable 30-plant shopping list for produce ideas and checkboxes you can take to the store.
Whole grains: 3 to 5 plants
Choose three to five different grains for the week. Oats at breakfast, brown rice in a grain bowl, and whole wheat bread already make three. Barley, quinoa, buckwheat, rye, farro, bulgur, millet, and sorghum give you room to rotate without changing every meal.
Whole grains bring different fibers and plant compounds into the diet. Human intervention trials suggest that whole grains can change the abundance of some gut microbes, although the trial results vary by grain, dose, study length, and the person's starting microbiome. That makes variety a more honest goal than expecting a particular grain to produce a particular microbial result.
A grain blend can cover several plants in one package. Check the ingredient list, since "multigrain" can still describe a product made mostly from refined flour.
Beans and legumes: 3 to 5 plants
Chickpeas, lentils, split peas, beans, and soy foods can all add variety. Pick three to five for the week, but remember that different forms of the same plant still count once: black beans and kidney beans are both common bean, while edamame, tofu, and tempeh are all soy. You don't need to buy every variety at once.
Beans and legumes provide fermentable carbohydrates that gut microbes can use. Across randomized trials, legume-rich diets changed some microbial metabolites and taxa, but the microbiome findings were not uniform enough to promise the same response for everyone.
Canned beans count and remove most of the prep. Rinse them, then add them to soups, salads, tacos, or grain bowls. If beans usually leave you uncomfortable, start with a smaller portion and build slowly rather than forcing a full serving to hit a number.
Nuts and seeds: 3 to 5 plants
Nuts and seeds are useful because they add variety without requiring another side dish. Pick three to five for the week, then rotate them through oatmeal, yogurt, salads, sauces, and snacks.
Walnuts, almonds, pistachios, chia, flax, pumpkin seeds, sesame, and sunflower seeds each count separately. A spoonful of tahini counts as sesame. Peanut butter counts as peanuts. Different forms of the same plant still count once.
A meta-analysis of randomized trials found that nuts altered the abundance of some gut bacteria, while overall diversity did not consistently change. Nuts and seeds still bring fiber, fats, and plant compounds to the diet; the evidence simply does not support promising a predictable microbiome shift from one handful.
Herbs and spices: 5 to 8 plants
This is where 30 starts to feel realistic. Basil, cumin, oregano, ginger, cinnamon, cilantro, and turmeric are seven different plants. Fresh and dried versions count the same way.
Aim for five to eight across the week by seasoning meals you already planned. Tacos might bring cumin and cilantro. Oatmeal adds cinnamon. Tomato sauce can cover basil and oregano. Curry may add ginger and turmeric. The amounts can be small because the 30-plant exercise is an inventory of variety, not a validated dose of each plant.
In a controlled feeding study, culinary amounts of mixed herbs and spices changed the abundance of some gut bacteria in adults at risk for cardiovascular disease. The analysis was exploratory, and the bacterial changes do not prove that spices improve gut health.
Fermented foods can add 1 to 3 choices
Fermented foods are a separate lane from plant variety. Add one to three if you enjoy them, but count carefully: sauerkraut adds cabbage, kimchi adds the plants in its ingredients, and tempeh adds soy. Yogurt and kefir can be part of the fermented-food goal without increasing the plant total.
In a 17-week randomized study of 36 healthy adults, a diet high in fermented foods increased gut microbiota diversity and reduced several inflammatory markers. It was a small study, and the fermented-food results do not establish that everyone needs fermented food or that more is always better.
Fermentation alone does not guarantee that live microbes remain when you eat the food. When live microbes are what you want, check the label for language such as "live and active cultures" or "contains live cultures." Shelf-stable or heat-treated fermented foods may be delicious without still carrying live cultures.
Download the printable 30-plant shopping list to keep plant variety and fermented foods straight while you shop.
A sample cart that reaches 30 plants
You can reach 30 without buying 30 separate packages. This sample uses overlapping meals and ingredients:
- Oats
- Blueberries
- Raspberries
- Banana
- Apple
- Spinach
- Kale
- Cabbage
- Carrot
- Broccoli
- Bell pepper
- Tomato
- Onion
- Garlic
- Avocado
- Sweet potato
- Brown rice
- Quinoa
- Whole wheat
- Chickpeas
- Black beans
- Lentils
- Walnuts
- Chia seeds
- Pumpkin seeds
- Cinnamon
- Cumin
- Cilantro
- Ginger
- Turmeric
Oatmeal with blueberries, raspberries, banana, walnuts, chia, and cinnamon covers seven plants. A grain bowl with brown rice, chickpeas, spinach, cabbage, carrot, pepper, avocado, cilantro, and cumin adds nine more. The number rises through combinations, not 30 separate recipes.
Foods to limit for better gut support
A varied grocery cart can still include food chosen for convenience or pleasure. The useful question is what takes up most of the cart and what it displaces.
Ultra-processed foods
Ultra-processed foods include a wide range of products, and the category alone does not tell you the nutritional quality of every item. Researchers have proposed several ways these foods or their additives could affect the gut, but a major evidence review found that much of the mechanistic work comes from animals or laboratory models and that human evidence remains limited.
Use "limit" as a shopping prompt when packaged foods are crowding plants out. It is not a reason to fear every packaged product.
Foods and drinks high in added sugar
High intakes of added sugar have been linked to changes in the gut microbiome, but a recent research review includes substantial animal evidence and does not prove that a specific dessert causes a specific microbiome change in a person.
Compare labels on foods you buy often, such as cereal, granola, sauces, and sweetened yogurt. Fruit does not belong in this category simply because it contains naturally occurring sugar.
Heavy alcohol use
Clinical studies in people with alcohol use disorder or alcohol-associated liver disease often find altered gut microbial communities and impaired gut-barrier function. Those clinical studies involve heavy, harmful use and cannot define a microbiome-safe drinking threshold for everyone.
If alcohol is difficult to cut back, or stopping causes shaking, sweating, nausea, anxiety, or other withdrawal symptoms, talk with a clinician rather than stopping abruptly on your own.
How to tell whether eating more plant variety is working for you
Eating more plant variety can change your fiber intake quickly. The first week may bring a change in stool frequency or consistency, more gas, or no obvious difference. Those outcomes do not measure microbiome diversity, and symptoms alone cannot tell you which microbes are present.
Track what you can observe: what you ate, stool form, frequency, urgency, bloating, and how you felt. Keep the rest of your routine fairly steady for a couple of weeks so five simultaneous changes don't muddy the pattern.
If you want that tracking to happen automatically, Throne One records stool consistency, frequency, and gut patterns over time without manual bathroom logging. It is a wellness device and does not diagnose, treat, cure, or prevent disease.
The challenge is working if it helps you eat a wider range of plants in a way you can sustain. Thirty is a prompt, not a pass-fail test.
Common questions about eating 30 plants a week
Do herbs and spices count toward 30 plants?
For this shopping challenge, yes. That is our practical convention, not a scoring rule validated by the American Gut study. Count herbs and spices for variety, not as a promise that a pinch changes your microbiome.
Do coffee, tea, and dark chocolate count?
For this shopping challenge, they can count in a broad inventory. That is a personal choice, not a rule established by the American Gut study. Keep the exercise honest: a diet built around coffee, tea, and several chocolate products misses the point of adding different whole plant foods.
Do canned and frozen foods count?
Yes. Freezing or canning does not change the plant species. Check labels for added sodium, added sugar, or ingredients that matter to your health needs.
Is 30 plants a week proven to improve gut health?
No. The American Gut result was an association from a self-selected, observational cohort. The widely cited comparison involved 41 people reporting more than 30 plant types and 44 reporting 10 or fewer; it did not prove that moving one person from 10 to 30 causes better health.
What if beans, whole grains, or some vegetables trigger symptoms?
Do not force foods that reliably make you feel unwell just to hit a number. Smaller portions, slower increases, or different plants may sit better. Persistent digestive symptoms, weight loss, blood in the stool, black stool, fever, severe pain, or symptoms that wake you at night deserve medical attention.
