Eating 30 different plant-based foods every week is gaining popularity as a simple way to support gut health and improve dietary diversity. The idea is attracting attention among health-conscious people who want to improve their eating habits without following complicated diets. BBC journalist Melissa Hogenboom decided to try the challenge for a week and ended up consuming around 51 different plant foods, exceeding her original target. The concept is linked to a 2018 study that found people who reported eating at least 30 different types of plants each week tended to have more diverse gut microbiomes than those consuming fewer than 10. A diverse gut microbiome refers to the variety of microorganisms living in the digestive system, which play an important role in overall health. According to researchers, eating a wider range of plant foods may help support these microorganisms and contribute to better health. However, the number 30 is not a strict medical requirement. Rob Knight, director of the Center for Microbiome Innovation at the University of California, San Diego, has noted that people may also benefit from consuming 20 or 25 different plants weekly. The potential benefits can vary depending on a person's existing diet and the variety of foods they introduce.

Which Foods Count Towards the 30-Plant Challenge?
The challenge is not limited to fruits and vegetables. It includes six broad categories: fruits, vegetables, whole grains, legumes, nuts and seeds, and herbs and spices. Foods such as oats, lentils, chickpeas, brown rice, quinoa, almonds, chia seeds, and leafy vegetables can all contribute to the weekly total. Tea, coffee, and chocolate are also sometimes included because they contain plant-derived compounds, although some approaches count herbs, spices, tea, and coffee as quarter-points rather than full points. Nutrition scientist Federica Amati of Imperial College London has highlighted the potential importance of adding a variety of herbs and spices to everyday meals. Small changes, such as mixing different spices into a curry or adding seeds to breakfast cereal, can help increase dietary diversity. Nutrition experts also recommend looking beyond familiar choices such as apples, cucumbers, and peppers. Whole grains, nuts, seeds, and pulses are important additions because they provide fibre and other beneficial nutrients. The goal is to include a broad range of plant foods rather than consume large quantities of only a few familiar ingredients. For people who are new to the challenge, starting with a few extra ingredients each day may be more manageable than trying to reach 30 immediately.

How One Week of Eating More Plants Made a Difference
During her week-long experiment, Hogenboom continued eating familiar meals while making small changes to increase the variety of ingredients. Her breakfasts included overnight oats, chia seeds, yoghurt, and different fruits. Lunches consisted mainly of sandwiches and leftovers, while dinners featured meals such as chickpea tagine, quinoa salad, vegetable curry, soup, tacos, and stir-fried noodles. She also included ingredients such as green lentils, asparagus, sweet potatoes, black beans, avocado, peanuts, sesame seeds, aubergines, and courgettes. Instead of purchasing expensive fresh produce every day, she combined fresh ingredients with frozen foods and cupboard staples. Planning meals in advance helped her avoid food waste and use leftovers for lunch the following day. Although preparing different meals required some effort, she found that the challenge was easier than expected. She also noticed that having a wider selection of ingredients encouraged her children to try foods they might otherwise have avoided. By the end of the week, she had counted approximately 51 different plants. Her experience suggests that improving dietary diversity does not necessarily require a complete lifestyle change or a large grocery budget. Adding nuts to breakfast, including beans in meals, choosing whole grains, and experimenting with herbs and spices can all help. The key takeaway is to focus on variety and build sustainable eating habits rather than treating 30 plants as a rigid target. A diverse, balanced diet can support gut health, although individual health benefits depend on overall dietary patterns and other lifestyle factors.