30 plants a week as a family: how the count really works

30 plants a week sounds like a project until you look at one evening. Tuesday's pasta is already 4 or 5: wheat, tomato, onion, garlic, basil. Nobody has ever looked at it that way. This is the family version of the guideline: what the 30 means, what counts, how everyone at your table shares one count and how to start a first week without anyone being measured.

What 30 plants a week means

The guideline comes from the American Gut Project, a large citizen-science study in which adults who ate more than 30 different plants a week had a more varied gut flora than adults who ate 10 or fewer (McDonald, 2018). It is an observation in adults, based on what people reported themselves. It says nothing about what the number does for a child, and we do not say it either.

What the number is, is a handy anchor. It shows that the point is not eating more, it is eating more different things. A household that rotates the same five vegetables sits well short of 30. The same household with a new legume and a handful of seeds gets a long way further, without a single portion growing. That is why we call it the guideline and not a target you hit or miss.

What counts as a plant

A plant is a plant food you can name. There are 8 types: fruit, vegetables, legumes, whole grains, nuts, seeds, herbs and spices. Each type counts once a week, however often you eat it. Apple on Monday and Wednesday is 1 plant, apple and pear is 2.

The rule is generous on purpose. The point is variety, not bookkeeping. Coffee, a potato, a spoon of ketchup, a pinch of cumin: most of the questions parents ask have a short and friendly answer. The full list, with every doubtful case in one table, is in the article on what counts as a plant.

Counting together as a household

Everyone at the table shares one count. The household counts per plant, not per person. If you eat the lentils and so does your partner, that is 1 plant. If your child only licks the lentils, that counts as well, because the household has now had them. Nobody has to eat their own 30.

That makes the number reachable in a way it is not for one person alone. Four people who each finish their own plate cover far more different plants than one person trying hard. One eats the olives, another the cucumber, a third tastes the parsley. Your list grows and nobody has to see their plate as a score.

How a whole week with four people at the table reaches 30 without cooking twice is laid out day by day in 30 plants a week for kids: one count for the whole family.

The tasting count is the child's side

There are two counts, and it helps to keep them apart. The household count belongs to the grown-ups: 30 plants a week, together. The tasting count belongs to the child: how often they have tasted something, on the way to liking it. Most children need 8 to 15 tastes of a new food before they accept it, sometimes more. A lick counts.

So a child is never measured against 30. Their game is smaller and closer: 2 more tastes and that plant's card levels up. Everything they taste feeds the household count, but the pressure sits with the adults only, and there it is a cheerful number. How to keep the tasting count without it turning into a project is in the article on how many times to try a food.

What an ordinary week adds up to

You do not need to cook anything special. A week of ordinary meals gets closer than you would think, because every meal has several plants in it.

• Breakfast. Oats with an apple, a spoon of seeds and cinnamon: 4 plants.
• Lunch. Bread with cucumber and tomato, a handful of nuts on the side: 4 or 5 plants, depending on the bread.
• Pasta with tomato sauce. Wheat, tomato, onion, garlic and basil: 5 plants.
• Soup or stew. Lentils, carrot, celery, onion and parsley: 5 plants, of which the onion is already counted.
• Rice with chicken and vegetables. Rice, pepper, broccoli and ginger: 4 plants.
• In between. A mandarin, a banana, popcorn: 3 plants.

That is an example, not a prescription. Add up a week of meals like these, take out the repeats and you are well on the way. The last few come from one new plant in the shopping, a herb in the wok or a different legume on Saturday.

Why variety beats quantity

The number counts types, not portions, and that changes how you look at a week. A second plate of broccoli on Thursday adds nothing to the count, a first spoon of black beans adds 1. For a household that is a relief: nobody needs to eat more, you only need to put something different on the table now and then.

The same logic is why meat and fish stay out of the count: they carry no fibre, so they add nothing to the variety the bacteria live on. The full reasoning, and why yoghurt and sauerkraut do count, is in why meat and fish don't count towards 30 plants a week.

It also works the way children know. A child who gets the same three vegetables every day has few chances to meet anything new. A child who finds one small new plant next to the plate each week builds their list slowly, at their own pace. The household variety and the child's tasting count pull in the same direction.

The shopping rule

The easiest way to grow the list is one question in the shop: which plant have we not had for three weeks. That is the whole rule. Pick that one and put it in the trolley. It can be a mushroom, a different colour of pepper or a bag of red lentils.

One new plant at a time is not much, and that is the point. A new plant only becomes an ordinary one when it comes back to the table, and then the child's tasting count starts running by itself. The household does not eat more, it eats a wider range.

Your first week

Start small. The first week is a measuring week, not a challenge.

1. Days 1 to 3: see what is already there. Note which plants reach the table. It is usually a surprising number.
2. Day 4: one new plant. Choose one that fits something you cook anyway and put it next to the plate.
3. Days 5 to 7: keep counting. Put the new plant on the table again, without comment, and see what happens.
4. Sunday: one look. How many different plants was it this week? That number is your starting point, not a grade.

A household that lands on 14 this week and 17 next week has nothing to correct. The guideline points a direction. A week that comes out lower than the last one is just a week with a lot of the same meals, and that happens to everyone.

What backfires

• Counting as a chore. If the number becomes one person's job, or a moment everyone dreads, it goes. One tap after eating is enough.
• A child's plate as a score. A child who hears that their plate counts towards a number has a reason to refuse. The tasting count stays small and the child's own, the household count stays with the adults.
• Comparing siblings. "Look, your sister had four." Nobody learns to like a food to beat a brother or sister.
• Cooking twice. A separate meal for the child, so the household reaches its number, works against the tasting count. One pan, several plants, and everyone takes what they want.
• The number as a verdict. A week of 12 plants is not a failed week. Do not say it that way, not even to yourself.

If you are worried about how your child eats

A counting game is meant for ordinary weeks. Talk to your doctor if your child is losing weight or not growing, if whole food groups are missing, if they gag or panic around new food, or if the worry is getting too big for you as a parent. There is help for that, and it fits the situation better than any counter.

How Project Food does this

Project Food is an app on your phone that counts with you, and with everyone at your table. Every plant is a card, and a card fills by tasting. After a meal you tap what was on the table, per person. The household ring shows how many different plants you have had this week, and a plant's card levels up at 1, 5 and 10 tastes. The catalogue holds 224 plants (checked 2026-09-24), herbs and spices included. The app gives no advice on weight or nutrition and promises nothing for a child. It is a counter, and something to talk about at the table.

To remember

• 30 plants a week is a guideline from research in adults, not a promise and not a test.
• Each type counts once a week. Variety beats quantity.
• The household has one count. A lick from your child counts.
• A child is never measured against 30. Their game is the tasting count.
• One new plant per shop is enough.
• Counting as a chore, a plate as a score and comparing siblings backfire.
• Weight loss, whole food groups refused, gagging or panic: talk to your doctor.