Experts say we need to eat 30 plants a week. This is how I fared

<span>The advice to eat 30 plants a week is based on a study of thousands of people which found those who eat a wide variety of plant foods have better gut health.</span><span>Photograph: PeilingLeeCopyright/Getty Images</span>
The advice to eat 30 plants a week is based on a study of thousands of people which found those who eat a wide variety of plant foods have better gut health.Photograph: PeilingLeeCopyright/Getty Images

That we’re supposed to be eating our vegetables is a piece of health wisdom so universally acknowledged that most of the time, we barely think about it. Since 1991, the dominant US public health message on the subject has been to “eat your five a day”, which means eat either five fruits and vegetables, or five servings of fruits and vegetables – start asking the people around you, and I think you’ll find nobody really knows.

The call for “five a day” (that’s cup-size servings, by the way) hasn’t quite panned out; the Centers for Disease Control and Prevention report that only one in 10 American adults are fulfilling their quota. Perhaps a new, more elaborate measure will help? In 2018, the British and American Gut Project, run by the University of California San Diego in the US, and Dr Tim Spector of King’s College London in the UK, offered a new message: instead of “eat five a day”, they started saying “eat 30 plants a week.”

Why do experts recommend eating 30 plants a week?

The advice to eat 30 plants a week is based on the project’s study of thousands of people – or, more specifically, their poop. It found those who ate a wider variety of plant foods – fruits and vegetables, but also seeds, nuts, whole grains and spices – had a more diverse gut microbiome. A wider variety of gut bacteria provides a basis for better overall health and wellbeing: greater resilience to withstand pathogens, better digestion and better brain function. Since the project published its message, other experts have joined the call for 30 plants a week; Catherine Rabess, a dietitian and NHS clinical lead, released her book, The 30 Plan, this February, while Dr Megan Rossi, author of How to Eat More Plants and Love Your Gut, claims eating a diverse range of plants is her only dietary rule.

Spector’s 30-a-week approach is explained in detail on the website of his company, Zoe, a biotech firm aimed at helping people better understand their personal nutrition needs, best known for its continuous glucose monitors. There, eating 30 plants a week is conveyed as a personal “challenge” – a self-test anyone can do at home by tracking the plants you eat.

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How does the 30 plants challenge work?

Here’s how it works: every individual plant you eat counts as one “plant point”, even if you only eat a small amount of that plant, like a couple of carrot sticks or one strawberry. Herbs, spices and garlic also count, but only for quarter of a point. Meanwhile, different colored versions of plants, like red and yellow bell peppers, count separately as a point each, since different colored plants contain slightly different amounts of vitamins, minerals and phytonutrients. But some items don’t count at all – like white rice and potatoes (they spike your blood sugar too much, according to Spector, and contain less fiber and nutrients than other plants).

Relatively simple processed foods like popcorn count, but if the food has more than a handful of recognizable ingredients, it probably doesn’t count; nor do any juices. The idea is to start with bolstering diversity, and worry about quantity later.

According to Joan Frank, assistant program director at the University of California, Davis department of nutrition, the idea of eating 30 plants a week is nutritionally unimpeachable and excellent for health unless you have gastrointestinal (GI) problems that may make fiber hard to digest, in which case, proceed with caution. However, “some people don’t have access to a variety of different plants. We would hate for people to think, ‘I can’t do this because I can’t afford it,’” she says. “You certainly get benefits from eating as many plants as you can,” she says, even if you can’t get 30 different ones every week.

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Can I eat 30 plants in a week?


I already eat a lot of plants, but at first blush, 30 sounds like a lot. Out of curiosity, I decided to see if and how I hit my weekly 30 without particularly changing my diet or doing a special shop. Here’s how it went.

Monday

Morning: Amazingly, coffee counts as my first plant (only a quarter point, though). I’ve been skipping lately, partially because it seems like a sad chore ever since I discovered I’m lactose intolerant and had to re-evaluate my passionate relationship with yoghurt.

Afternoon: Lunch is a dynamite roll and a futomaki – so, I can add seaweed, cucumber, avocado, lettuce (Spector calls iceberg lettuce “pointless” and “useless”, but luckily I think this was green leaf), as well as mushroom, carrot and pickled ginger, which I count as a spice.

After lunch I had the last morning glory muffin from a batch I baked on the weekend. The batter contained carrot, apple, banana, fresh ginger and turmeric, pineapple and pecans. The serving sizes are truly negligible, but for sheer variety, I’m going to count them. The Zoe TikTok account has a post about how “all the best cakes have vegetables in them”, so I think they would approve.

A couple of hours later, I wanted another snack and had some okra chips and mangosteen. It was an incredible coincidence for me to buy the latter, one of my most favorite and rarely eaten fruits, before this experiment. They look and taste like fairy Pokémon.

Evening: Made a riff on a previously successful dinner that came out less successful but nonetheless contained chicken, kale, kabocha squash, butter beans, tomato and, for spices, garlic, lemon zest, fresh thyme and parsley.

Tea counts as quarter of a point; I had a mint blend.

Then, a few bites of coconut milk cookies ’n’ cream ice cream. Technically coconut and chocolate both have a place in the Spector-verse, but I reckon not like this.

Daily total: 18 points

Tuesday

Morning: Black coffee again, and then around noon I had a little concoction comprising a frozen cube of blended ginger, frozen pineapple, parsley, cucumber, lemon juice, water and a pinch of salt. I had all of these plants yesterday, so none of them count.

Had a few crackers with olive tapenade (it’s a small amount, but Rabess counts olive oil as ¼ point, so I will do that here).

Afternoon: Lunch was leftovers from last night and more mangosteen. Then, a cup of green tea.

Later, at a cafe, I had a mint tea and a pear danish.

Evening: Dinner was a white rice bowl with some squash, cucumber, pickled ginger, seaweed and pork floss.

Daily total: 1.5 points

Running total: 19.5 points

Wednesday

Morning: Black coffee; then I made a smoothie with almond milk, protein powder, banana, a few blueberries and freezer burned mulberries.

Lunch: A Spartan lunch of chicken and rice; it was what was in the fridge.

Evening: In the 30-plants challenge, even a small quantity of the plant counts. Still, eating tiny bits of thyme in a recipe or, a sliver of mushroom in my futomaki doesn’t get me even remotely near the CDC’s recommendation that “adults should consume 1.5–2 cup-equivalents of fruits and 2–3 cup-equivalents of vegetables daily to support a healthy immune system and prevent chronic diseases”. To up my volume, I decide to make minestrone soup for dinner.

It contains red onion, celery, garlic, canned tomatoes, kale, carrots, kabocha squash, white potatoes, a chayote that was in my crisper for two weeks but was still perfect, and the last of my parsley and thyme. I also eat a tangerine.

Daily total: 6

Running total: 25.5 points

Thursday

Morning: Coffee and a stalk of asparagus while cooking brunch for my grandpa.

Lunch: At a co-working session, I have shakshuka, which contains tomatoes, lentils, onion, red pepper and arugula, and a glass of hibiscus lemonade (sugary drinks don’t count).

Evening: At a cooking class my boyfriend booked, we make three dishes: Mexican short rib in a braising liquid full of spices; cod with red curry sauce and green papaya salad; and pork tenderloin with lemon-cashew fried rice.

Daily total: 6, plus two-odd points’ worth of spices (each dish had several, including mustard seeds, four varieties of chilis, cilantro and cumin).

Running total: About 33

Conclusion

Well, I killed it. This challenge gamifies plant intake, and I can feel myself already looking for places to add more; perhaps I could add smaller amounts of different berries in a smoothie, sprinkle hemp and chia seeds on top of peanut butter toast or try gremolata on a tray of roasted veggies.

It would be even easier to up my number by buying a mix of different apple, pepper or onion varieties at the store, and picking up frozen vegetables like edamame, peas and cauliflower, which are generally more affordable than fresh, and can last months.

Best of all, adding more plants doesn’t only contribute to gut health and make food taste better, but focusing on plant-based food sources over animal-based ones is generally more sustainable (with the exception of the international shipping on my mangosteens). Perhaps that will be my next challenge: 30 plants a week on the 100-mile diet.