For optimal gut health, diversity is key - and as a general rule, the more diverse your diet, the more diverse and healthy your gut will be. Dr Hazel Wallace shares her tips on how to get 30 different plants in your diet to help support your gut microbiome.
Where did the rule of 30 come from?
The 30 different plants - or plant points - recommendations comes from a study from 2018 that compared the gut microbiome of over 10,000 volunteers, mainly from the US, UK and Australia. (1) This study found that those who consumed more than 30 types of plants per week were more likely to have a healthier, more diverse gut microbiome, as compared with those consuming less than 10 types of plants per week. Interestingly, this plant diversity was seen to be more important than following a vegan or plant-only diet (1). Other studies have also found that consuming a variety of plants in the diet is associated with improved gut health (2).
Why plant diversity is so good for your gut
Plant-based foods (fruits, vegetables, wholegrains, nuts, seeds, beans and pulses) can contain a variety of important nutrients such as vitamins, minerals, antioxidants, carbohydrates, protein, fats and fibre. Each plant has a different nutrient profile and so by diversifying the types of plants you eat - you get a more varied intake of nutrients.
Fibre is a key component of plant-based foods and is one of the most important nutrients for gut health. Certain types of fibre can be fermented and used to feed healthy gut bacteria (3). This fermentation process also produces short chain fatty acids (SCFA) which feeds and protects cells in the gut lining and may also be beneficial when it comes to immunity and metabolic health (4). Fibre also helps with the movement of stools through the digestive system, and therefore prevents constipation and related conditions, like piles.
How to get 30 plants per week
It’s important to note that when we talk about “plants” we mean all different types of plant based foods so, while that includes fruit and vegetables, it also includes beans and pulses, nuts and seeds, wholegrains grains - even herbs and spices.
Each different plant-based food counts towards a point (herbs and spices count for a quarter of a point), regardless of the portion size, as it’s the variety of food which makes all the difference. But remember that a portion of fruit and/or vegetables for the ‘5-a-day’ rule is 80g/serving to count.
5 easy tips to help you get there:
- When it comes to snacks, grab a mixed bag of nuts instead of a single type of nut, or choose a mixed fruit salad instead of a pot of mango on its own, for example. This is a simple swap that shouldn’t require a change in cost or habit.
- Add beans and lentils to your meat-containing meals, either instead of the meat or on top of. Beans, chickpeas and lentils are also quite cheap sources of protein compared to meat and fish, so it’s a great way to save money too! You can also buy cans of mixed beans and mixed packets of grains that have more than one type which can be a quick way to bump up your points.
- Make the most of your freezer and fill it with mixed frozen fruit, to add to smoothies or porridge, and frozen veggies to add to stirfry’s, curries and stews.
- When grocery shopping, if you always find yourself picking up one type of vegetable, try swapping it out for another. For example, if you always choose red peppers - this week choose yellow! Or swap it out for a courgette or aubergine.
- If you’re buying salad leaves, a simple swap can be to go for a mixed bag of salad with different varieties.
Having a diverse intake of plants in the diet can play an important role in nourishing a healthy and diverse gut microbiome, which is likely to have a knock-on beneficial impact on overall health. The research suggests that aiming for 30 plants per week leads to improved gut health, compared to those who eat 10 or less.
As always when it comes to nutrition, this recommendation does not need to be the “rule”. The aim behind the recommendation is to increase the diversity of plant-based foods in the diet, so it might be more realistic for many people to aim to work on this more gradually. For example, if you currently usually consume 7-8 different types of plants each week a good starting point could be aiming for 10-12, then 12-14 etc.
Reaching this number may feel overwhelming in the beginning but once you get started you will be surprised how quickly you will reach 30 once you become more aware of the different plants you’re eating - and hopefully these tips will help you get there.
Hungry for more? Dig into our favourite gut-loving recipes.
References(1)McDonald, D., Hyde, E., Debelius, J. W., Morton, J. T., Gonzalez, A., Ackermann, G., ... & Knight, R. (2018). American gut: an open platform for citizen science microbiome research. Msystems, 3(3), e00031-18. [accessed April 2022 via: https://pubmed.ncbi.nlm.nih.gov/29795809/]
(2) Heiman, M. L., & Greenway, F. L. (2016). A healthy gastrointestinal microbiome is dependent on dietary diversity. Molecular metabolism, 5(5), 317-320. [accessed April 2022 via: https://pubmed.ncbi.nlm.nih.gov/27110483/]
(3) Chassaing, B., Vijay-Kumar, M., & Gewirtz, A. T. (2017). How diet can impact gut microbiota to promote or endanger health. Current opinion in gastroenterology, 33(6), 417. [accessed April 2022 via: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6005665/]
(4) Blaak, E. E., Canfora, E. E., Theis, S., Frost, G., Groen, A. K., Mithieux, G., ... & Verbeke, K. (2020). Short chain fatty acids in human gut and metabolic health. Beneficial microbes, 11(5), 411-455. [accessed April 2022 via: https://pubmed.ncbi.nlm.nih.gov/32865024/]