A new dietary recommendation from nutrition experts is challenging the well-established “five-a-day” fruit and vegetable rule, advocating instead for a remarkably diverse plant-centric approach. Recent research and expert opinion report that regularly consuming 30 different plants per week—far surpassing the classic advice of five daily servings—may substantially improve gut health and overall wellbeing. This shift, supported by findings from major studies such as the American Gut Project, is sparking conversation in Thailand and across the globe regarding how dietary diversity can transform modern eating habits and public health.
The significance of this “30 plants” strategy comes at a time when dietary-related diseases are on the rise worldwide, including in Thailand, where ultra-processed foods, high sugar intake, and declining consumption of traditional plant-rich diets are contributing to health burdens such as obesity, diabetes, and metabolic syndrome. Against this backdrop, the move to promote not just the quantity but the diversity of plant foods reflects a critical paradigm shift, one underscored by international and local research.
The new approach is championed by nutritionists including the head nutritionist at FuelHub, who says, “Thirty plants a week is definitely achievable if you take the necessary steps. Each plant food counts as ‘one plant’ or ‘one point’… You can mix up your meals by adding different vegetables to salads and stir-fries, choose plant-based snacks such as nuts, seeds and fruit, and also use herbs and spices like basil and turmeric as this can also count.” For busy Thais, these suggestions may be easier than ever with the abundance of fresh vegetables, fruits, whole grains, nuts, seeds, and aromatic herbs available at local wet markets, supermarkets, and even urban home gardens (Mirror article).
Backing this advice, the 2018 American Gut Project—a landmark citizen-scientist initiative involving more than 10,000 participants—found that people who consumed at least 30 distinct types of plants each week had a significantly more diverse gut microbiome compared to those whose diet included fewer than 10 plant types. Microbiome diversity is widely recognized as a crucial factor in supporting digestion, immune system effectiveness, mood regulation, and disease prevention (Wikipedia: American Gut Project). Additional research continues to confirm that such dietary practices are linked to lower chronic disease risk and improved health outcomes (ZOE guide, Cigna Global blog).
Gut health expert Professor Tim Spector, who appeared on the ZOE podcast in 2024, argued that “this 30, you know, it may have been plucked out of the ether somewhat, but as well as the public loving it and it’s being achievable—for many people, now we have a randomised controlled trial to say that diversity of plants put together have a very rapid effect on transforming many people’s gut microbes.” This perspective is transforming nutrition conversations among Thai health professionals and policymakers, who are increasingly attuned to the pivotal influence of the microbiome (Guardian coverage).
Within Thailand, traditional diets were already rich in plant diversity, with sticky rice, glutinous or brown rice, myriad vegetables, mushrooms, beans, tubers, and a dizzying variety of herbs and spices underpinning daily meals. Studies of urban and rural Thai populations reveal that “high-vegetable Thai traditional diets [confer significant benefits on] gut microbiota,” while high-fat, less-vegetable, Westernized diets are associated with reduced microbiome diversity, increased obesity, and higher rates of chronic disease (Frontiers in Microbiology, 2018, PubMed Central, 2018). Additional research in Thai populations confirms that urbanization and modern dietary changes are putting traditional microbiome advantages at risk (PMCID: PMC9866083).
Plant diversity, not just plant volume, is the crucial innovation here. Instead of simply eating more vegetables or fruit, the goal is to consume a greater variety across categories: different types of leafy greens, root vegetables, pulses, edible flowers, grains, nuts, seeds, and many kinds of herbs or spices. The head nutritionist at FuelHub explains, “Having a number of vegetables with each meal, fruit with breakfast and plant-based snacks in between can significantly improve your plant uptake… Use plant-based foods as toppings by adding nuts, seeds or herbs to your meals. This is an easy way to boost intake without much effort. A good example is adding chia seeds to your yoghurt or oats. Other meal ideas include smoothie bowls and rainbow salads.”
These small adjustments are linked to big health dividends. According to the American Gut Project, individuals with greater plant diversity in their diet exhibited more resilient microbiota populations, which are associated with enhanced resistance to pathogens, improved metabolic outcomes, and potentially lower rates of allergies and autoimmune diseases. While the “30 plants a week” recommendation sounds daunting to some, experts argue that batch cooking and “rainbow” meal preparation strategies make it feasible, especially if Thais draw inspiration from traditional recipes rich in plant-based ingredients. Modern dishes, such as smoothie bowls, are easily customizable to include Thai fruits like mango, papaya, dragonfruit, as well as imported superfoods.
The nutritionist at FuelHub emphasizes that this is more than a dietary fad: “This concept comes from gut health research, so should be differentiated from a typical fad trend. As great as eating 30 plants a week is, it’s more difficult to track, which may seem a rigid challenge to some people, but given the robust evidence of plant diversity, it could be a good addition to the broader dietary advice.” The NHS continues to recommend balanced caloric intake (around 2,500 calories daily for men and 2,000 for women), emphasizing that plant diversity is an enhancement, not a replacement, for overall energy and nutrition guidance.
Importantly, there are emerging efforts to bring this practice to the fore in public health communication. Several online resources, including printable tables and weekly trackers, help individuals tally their plant servings and discover new foods (Nutrition Connection resource). For Thai families, schools, and communities, engaging children and elders in the “rainbow diet” can revive interest in underappreciated indigenous or seasonal produce, such as winged beans, Thai eggplants, or various wild mushrooms.
However, some health professionals caution that achieving 30 unique plant foods may still pose challenges for individuals with constrained food budgets, allergies, or rural dwellers with limited access to supermarket variety. For these groups, nutrition outreach programs and local farming cooperatives can play a vital role in expanding food diversity while maintaining affordability.
Globally, the “30 plants a week” recommendation is attracting support because it echoes a broader scientific consensus: gut microbiome diversity is a key foundation of human health. A recent PubMed-indexed review notes, “Dietary patterns characterized by low-glycemic, minimally processed plant foods are associated with lower risk of several chronic diseases” and that metabolic plasticity—how the gut microbiota quickly adapts to different plant foods—underscores the resilience of our digestive ecology (PubMed Search: Metabolic plasticity of the gut microbiome).
Thai culture’s rich plant traditions may make this transition more accessible compared to highly urbanized Western societies. Centuries-old dishes like phla (herb-laden salads), nam phrik (vegetable dips with fresh-cut veggies), or multi-herb soups demonstrate natural strategies for achieving high plant variety. Street market stalls and village gardens feature diverse edible leaves, roots, beans, and fruits used in all meal types, from breakfast congee to night market snacks.
Looking ahead, experts suggest that future public health campaigns in Thailand and Southeast Asia will increasingly stress plant diversity, leveraging modern digital tracking apps, community gardening projects, and culinary education in schools. There is strong potential for collaboration between local chefs, health authorities, academics, and the tourism sector to simultaneously boost health and showcase Thailand’s biodiversity to visitors.
Practical recommendations for Thai readers include: keeping a simple checklist of plant foods tried each week; swapping white rice for mixed grains; adding locally available pulses to main meals; experimenting with unfamiliar herbs or edible flowers; and including more nuts, seeds, and whole fruits in snacks and desserts. For busy working adults or families, meal-prep days at the start of each week can ensure that a colorful variety of plant ingredients are on hand for stir-fries, curries, or soups.
In conclusion, while the “five-a-day” method remains a helpful guideline, the new “30 plants a week” approach offers an exciting, evidence-based upgrade that leverages traditional Thai eating patterns for modern health. As Thai society faces growing health challenges stemming from globalization and dietary change, embracing plant diversity could offer a pragmatic, sustainable route to improved wellbeing for all. Readers are encouraged to start small—trying just one or two new plant foods a week—while supporting local farmers and exploring the botanical riches found in every Thai community.
Sources: Mirror, American Gut Project (Wikipedia), Frontiers in Microbiology, PubMed Central, ZOE, The Guardian, Nutrition Connection, Cigna Global, ScienceDirect, PMCID: PMC9866083