2026 marks not only the 50th anniversary of Herne Hill School but also the 10th anniversary of the school’s food provision and education programme – a good opportunity for a retrospective on how it was developed and has evolved.
The photo above shows Pre-Reception eating family-style in their classroom, like the Kindergarten children. The Pre-Prep children eat buffet-style in the Oak hall.
Ambitious objectives from the get-go
‘Food and Drink’ is one of the five essential and interrelated building blocks of the ‘House of Good Health’ we establish together with the children alongside ‘Mindset’, ‘Sleep’, ‘Exercise’ and ‘Environment/Nature’. Since the inauguration of our Oak building in 2016, we are not only able to talk about it but can also experience it daily.
From the outset, we were aware of the huge opportunity this would offer to help shape the long-term health of our pupils, and we have therefore invested significant effort in devising a special, high-quality and age-appropriate programme. As we were not encumbered by historic infrastructure or traditions, we had the chance to devise something special that reflected the latest nutrition and child development research and best practice.
At the origin was designing the large kitchen in the basement of the Oak building to a spec that would enable the realisation of our ambitious aims. By working with a highly experienced catering kitchen designer and engaging with leading, high-end independent school and nursery caterers, we managed to build a kitchen which all caterers considered to be state-of-the-art. We later, in 2020, duplicated this process when we built/designed the kitchen at 99 Herne Hill for our dedicated Kindergarten.
Broad-based, expert input
When in 2015 it came to defining in greater detail the food offering we would actually be providing from 2016, we engaged in further extensive dialogues with the development chefs and nutritionists of the two best catering companies that had emerged from our tendering process (since summer 2018, we have successfully partnered with one of them, Wilson Vale). This included multiple site visits to their best practice schools as well as creative brainstorming sessions during which we established the following key hallmarks of our provision:
- Bespoke menus developed on a weekly basis to avoid menu fatigue and facilitate seasonality.
- Everything being prepared from scratch on site daily, with high-quality seasonal produce and authentic ingredients, i.e. no processed or pre-prepared frozen food.
- Tasty and flavoursome food as there was unanimity among the experts that young children’s food does not need to be bland and that they can be encouraged to be adventurous.
- Wide variety of cuisines and ingredients, with everything provided ‘in moderation’ and with very low sugar levels.
- Continued adherence to our historic nut-free policy but otherwise safe catering to the widest possible range of allergies.
In these brainstorming exchanges, we were initially driven by a desire to combine the best of the traditional, highly balanced Mediterranean diet (with its large variety of plants, legumes, nuts, seeds, olive oil but also pasta and rice, fish, meat, milk and fermented foods and drinks) with additional aspects of the Asian diet (which is also very varied, contains additional plant products such as tofu, and in which fermented products such as kimchi or miso play a key role), as their health benefits have been widely recognised.
Incorporation of the new gut microbiome science
Our dietary knowledge and insights expanded substantially in summer 2015, when we came across Prof. Tim Spector’s ground-breaking first book on the gut microbiome: “The Diet Myth – The Real Science Behind What We Eat”. We had encountered it as a highly recommended ‘Summer Science Reading’ in the Financial Times, which described it as follows:
“The microbiome, the population of 100tn or so microbes inside the human body, has a huge influence on our health, which science is only now beginning to understand. Spector has written the best of a bunch of good new books about our microbial guests, focusing on their role in promoting healthy digestion and avoiding disease.”
We were fascinated to discover that:
- As humans, we are ‘holobionts’ – biological systems consisting of the host organism and 100 trillion of symbiotic microorganisms (bacteria, archaea, viruses and fungi) who live on and within us in a synergistic relationship that benefits both the host and the microbial species.
- Within ourselves, we have 1.3 times more microbes than human cells.
- The genes in our microbiome outnumber those in our genome by about 150 to 1.
- 95% (or about 95 trillion) of our microbiota are located in the gastrointestinal tract; they weigh about 2 kg, i.e. around 50% more than the average brain.
- Every person’s microbiome is unique, just like our fingerprints; it can vary greatly from individual to individual.
Medical benefits and implications
As interesting as these new facts were for us at the time, what has turned out to be even more revelatory and relevant for our catering purposes is what we have learned about the huge importance of the gut microbiome for our health, and how it can be influenced.
We now know that a healthy gut microbiome:
- has profound and far-reaching health benefits, including
- enhanced digestion and nutrient absorption;
- production of essential vitamins and short chain fatty acids;
- powerful support of the immune system;
- improved mental health and mood via the bi-directional connection with the central nervous system (the ‘gut-brain axis’); as well as
- substantial contribution to the prevention of disease, including mental conditions (dysbiosis, i.e. an unhealthy gut microbiome, is associated with an ever-expanding range of diseases);
- is primarily defined by high microbial diversity and balance, which are key to enabling functional complexity; and
- can be moulded, nurtured and supported, primarily through diet, but also through a variety of other environmental and lifestyle factors such as avoiding antibiotics when not necessary, exercise, sleep, etc.
Below is an overview of what we have learned to ideally eat and avoid eating to promote a diverse and balanced gut microbiome.
In a nutshell, the most impactful way to sustain a healthy gut microbiome ecosystem is to feed it with a diverse, wide variety of ‘whole’ (as opposed to ‘processed’) foods and plants containing lots of fibre and polyphenols/antioxidants, supplemented by probiotic fermented foods.
Weekly veg, fruit and flavour
It was this realisation that led us to incorporate yet more seasonal produce into our menus and introduce, in 2019, an educational taster tray programme for the children in the Reception Cycle and Key Stage 1.
Every week, our chefs prepare a taster tray for each class for the teacher to introduce to them a seasonal veg, fruit and flavour (typically a spice or fresh herb) so that each child can learn about and experience the produce in question.
Whilst the foundations for this learning are laid in Pre-Reception, it is really in Reception and Key Stage 1 that it comes into its own and solidifies, when the children become increasingly accustomed to and enjoy trying new flavours over the course of their three Pre-Prep years.
It goes without saying that it is paramount to serve them high-quality, ripe produce. Indeed, when a child tastes, say, an apricot for the first time, we want it to be fully ripe, soft, juicy, flavoursome and sweet – and not a green, hard and acidic one that could put them off for a long time. First impressions matter greatly!
Obtaining the best produce is, of course, best achieved through a seasonal approach, which incidentally also helps the budget and our carbon footprint due to reduced transportation. In this regard, we have been delighted to be working since 2020 with Fresh Connect, a superb family-owned greengrocer based in New Covent Garden Market. We talk to them regularly about what’s coming up that is good and abundant.
How does a gut microbiome develop?
Although the speed with which science has uncovered previously unknown biological mechanisms related to our gut microbiota over the past 15-20 years has been extraordinary, much more remains to discover. This is particularly the case with how a gut microbiome develops and evolves over a lifespan, and especially in children.
In many ways, we already know a lot, as articulated eloquently by Prof. Susan Lynch of University of California San Francisco’s Benioff Center for Microbiome Medicine in her highly educational video lectures (see Further Reading for links):
- We are not born with a set of microbes that we then nurse throughout life, but with a very simple microbiome inherited from our mother that then evolves with us in a symbiotic, mutually dependent manner.
- During the first three years of life, a very rapid accumulation of microbes occurs in the gut, with their distribution starting to resemble that of an adult microbiome.
- However, the functional capabilities of the microbes accumulated by a 3-year-old are vastly different from those seen later in adolescence and adulthood.
- Throughout life, the microbiome remains dynamic but is actually quite resistant and difficult to change significantly once formed.
- As we decline and enter the senior years, our microbiome continues to evolve, with a loss of diversity quite characteristic.
The emphasis placed on postnatal infancy is understandable as there has been a strong desire to better understand the apparent benefits of natural birth over c-section, breast milk over formula and the avoidance of anti-microbials as well as the impact of weaning. Furthermore, as the extremely rapid accumulation of microbes and their genomes during infancy coincides with a critical window in immune development, there is great interest from researchers like Prof. Lynch to further study the early infancy gut microbiome with the aim of identifying microbial predictors of allergy and asthma risk in later childhood. As explained in her September 2025 video, some amazing results are beginning to emerge (see Further Reading).
Supporting children’s gut microbiome development during their Early Childhood Education period
By contrast, we still know relatively little about the development of the microbiome in children over the age of three years. In the review “The Gut Microbiota in the First Decade of Life” published in “Trends in Microbiology” in Dec. 2019, the authors quote research showing that only about 3% of the gut microbiota samples that had been analysed by metagenomic shotgun sequencing at the time had been carried out on children aged 3 to 18 years old (whereas samples from 0-3 year-old infants accounted for over 20%). Still, they have collated some interesting findings from a variety of research conducted around the world, including:
- One study showed that children aged 3-4 years still had a lower microbial diversity than adults.
- Another found that microbial diversity at five years of age was still significantly lower than that in adults.
- A further study combining both taxonomic and functional analyses of the gut microbiome of children aged 7-12 years found significant differences in the relative abundance of certain types of bacteria and genes, resulting in differentiated microbiota functionality.
Overall, they concluded that although the structure of the gut microbiome of children aged 3+ years is similar to that of adults, there are substantial compositional and functional differences. The bottom line seems to be that microbiota richness, diversity and especially functionality continue to evolve significantly even after the very rapid postnatal evolution in infancy. This is perhaps not surprising as it appears to mirror other domains of human development, notably that of the brain.
Could the evolution of the gut microbiome resemble that of our human brain?
In the brain’s case, infancy is marked by an extraordinarily rapid formation during the first three postnatal years of synapses connecting our neurons. They peak at about 1,000 trillion at the age of around three years, when a process of pruning and maturation sets in to strengthen those we learn to need the most, and to discard those that are superfluous.
The steepest curve of this process is in its beginning years, i.e. around the ages of four, five and six, and eventually leads to the halving of synapses by adulthood to about 500 trillion. This does indeed appear to be remarkedly similar to the extremely rapid accumulation in infancy of gut microbes and their genomes, and therefore their functional genes into the gut microbiome, with this functionality then being improved and honed in childhood, with presumably the early childhood years mattering the most.
Of course, only time, and much more research through complex longitudinal studies, will tell if our hypothesis is correct. However, as long as it is not disproven, the fact that the children’s Herne Hill School years are likely to be so formative for the development of a healthy gut microbiome provides us with a great sense of responsibility and motivation to do all we can to enable this.
We know for sure that the children joining us in Kindergarten and Pre-Reception are primarily still into beige foods, and by the time they graduate at 7+, we want them to have tasted and learned to appreciate every vegetable, fruit and flavour they will encounter in any good grocery store over the course of a year. We also want them to have developed healthy eating habits and patterns that will hopefully last their lifetime.
Figures just published in November 2025 by the National Child Measurement Programme, which records the height and weight of more than 1 million primary school children in England each year, show that 10.5% of Reception class children were obese in 2024-25, and that this jumps to 22.2% by Year 6, the last year of primary school. Our aim is to do all we can to help reduce that risk for Herne Hill School graduates.
An example of our reliance on gut microbes to harness their goodness
Pomegranates are an amazing ‘superfruit’ providing lots of health benefits, including counteracting the muscle weakening associated with old age.
They and their juice are rich in ellagitannins, a group of antioxidant polyphenols, which certain gut microbiota are able to metabolise into ellagic acid and from there into various urolithin compounds, which do not exist in nature as natural molecules. Absorption of these urolithins then triggers improved functioning of our mitochondria (the microscopic power packs that provide, amongst other functions, energy to muscle cells) by stimulating the process that recycles old and damaged mitochondria into new ones.
However, this does not seem to work for everyone, with the essential prerequisite being the presence of the right gut bacteria. This is a prime example for why we consider it to be so crucial to help establish and feed healthy, diverse microbiomes in our young children.
Walnuts, cloudberries, raspberries and particularly yellow raspberries are also rich in ellagitannins. Similar mechanisms of other useful molecules and functional benefits being produced by the gut microbiota are likely to exist for many other superfruits like blueberries, strawberries, acai, goji, avocado, citrus fruits, etc.
Microbiome 101: Frequently Asked Questions
Introduction on the gut microbiome from APC Microbiome Ireland, a world-leading research centre linked with University College Cork, focused on understanding the gastrointestinal bacterial community and harnessing the power of the microbiome.
How the Gut Microbiome Affects Children and Why It Matters
Overview by JM Nutrition, a nutritional counselling service by nutritionists and dietitians across Canada.
The Gut Microbiota in the First Decade of Life
Dec. 2019 Review published in “Trends in Microbiology”.
How Do Infant Microbiomes Influence Childhood Health
March 2022 Video from University of California Television with Prof. Susan Lynch from UCSF’s Benioff Center for Microbiome Medicine.
How Prenatal and Infant Microbiomes Shape Childhood Allergy and Asthma
Sep. 2025 Video from University of California Television with Prof. Susan Lynch from UCSF’s Benioff Center for Microbiome Medicine.