For 18 months, until she died in her sleep last year at the age of 117, Maria Branyas Morera was the oldest living person on Earth. Born on March 4 1907 in San Francisco, US, to Catalan parents, and resident in Spain from the age of eight, the supercentenarian (a person aged 110 or older) has been the focus of intense scientific interest since she passed away in August 2024.
Researchers seeking to uncover the secret to Morera’s longevity have studied her gut microbiome and published a paper on their findings. While the results have not yet been peer-reviewed, they provide a fascinating insight into dietary and lifestyle choices that could help to extend our lifespan.
An analysis of Morera’s genes and microbiome revealed that cells in her body functioned as if they were 17 years younger than her actual age. The study found that Morera had an exceptionally healthy gut, with what it describes as an “anti-inflammatory” microbiome showing high levels of bifidobacterium – a genus of gastrointestinal bacteria, also known as gut microbiota, that resides in our digestive tract. According to the researchers, her microbiota “mirrored that of an infant”.
Before her death, Morera told an interviewer that her longevity was because of a range of factors: she avoided alcohol and smoking, enjoyed daily walks, and followed a diet rich in fruits and vegetables, as well as eating three yogurts a day. She also had friends and family around her and “avoided toxic people”.
“As a dietitian and nutritionist, I find it fascinating to look at what centenarians and supercentenarians eat,” says Dr Megan Rossi, the founder of The Gut Health Doctor and a research fellow at King’s College London. “The principles Morera lived by very much support optimal gut health, and one of the things the research showed was the diversity of her gut bacteria. Currently, that is considered one of the best markers of someone’s gut health.”
Individuals with a greater variety and “balance” of microbes in their gut seem to have a lower risk of experiencing around 70 different chronic conditions, ranging from heart disease to Type 2 diabetes, as each type of bacteria or microbe does something different for the body. “If you’ve got lots of different types of microbes inside you,” says Dr Rossi, “you’ve essentially got more skills. In a sense, they’re doing a wider range of jobs for you.”
For this reason, experts believe good gut health promotes longevity – by protecting us from the various ailments that approach in older age, conditions that have the potential to end our lives prematurely.
Health lessons from a supercentenarian
When considering the case of Morera, it’s important to remember two key things. Firstly, in her own words, she was blessed with “luck and good genetics”. Secondly, it was not just one factor but a combination of dietary and lifestyle choices that enabled her to reach such a ripe old age…
1. She ate three yogurts a day
It may be tempting to deduce from this that “if you eat three yogurts a day, you’ll live longer”, but the reality is more nuanced. Moreover, Dr Rossi points out, it’s not just yogurt but a wide range of other fermented foods, including kefir, kimchi and sauerkraut, that have been shown by research to be beneficial for gut health. “We know that fermented foods are associated with increasing your microbial diversity,” she says, “and some studies have even shown that eating them reduces inflammatory markers in the body.”
Inflammation is associated with an array of health problems including atherosclerosis (narrowed arteries), cancers, metabolic disorders, coronary artery disease, obesity and chronic lung disease. While more research is needed to understand the connection, nutritionists believe that consuming fermented foods will reduce it. But how exactly is eating a yogurt better for us than, say, drinking a glass of milk?
“When you take something like cow’s milk and add certain bacteria to it [to create yogurt], those bacteria change the structure of some of the milk proteins and sugars,” explains Dr Rossi. “They break down the lactose [sugar] and produce organic acids, which have been associated with various health benefits. They also change the structure of some of the proteins to make them bioactive proteins, which are thought to have heart health benefits. In other words, the fermentation process produces active chemicals that we wouldn’t just get from cow’s milk alone.”
It’s worth noting – before you dig into that Müller Corner – that some yogurts are more effective than others. Make sure you choose a plain, unsweetened yogurt with a high concentration of live and active cultures and no emulsifiers.
2. She ate a diet rich in fruit and vegetables
“If we look at Morera’s lifestyle,” says Dr Rossi, “she was very much eating a Mediterranean diet. People with optimal gut health tend to eat a range of different plant-based food groups that I call the ‘Super Six’. This consists of whole grains, such as quinoa, wheat and oats; vegetables; fruit; nuts and seeds; herbs and spices; and finally, legumes – things like chickpeas, lentils and butter beans. Each category provides your gut bacteria with different types of fertilisers. For me, the two key principles for optimal gut health are: eating across the Super Six most days and having fermented food in your diet.”
She adds that embracing a more gut-friendly diet is a lifestyle choice rather than a quick fix: “Once you’re in the habit, it’s actually quite easy to maintain, but the truth is that if you stop eating a diverse range of plants, your microbiome can change after a couple of days. So when we’re thinking about good gut health, it’s a marathon, not a sprint.”
3. She exercised regularly
Moderate exercise offers numerous health benefits and can reduce the risk of serious illnesses such as coronary heart disease, stroke,Type 2 diabetes and cancer. Research also suggests that exercise can enhance the number of beneficial microbial species in your gut and increase microflora diversity, boosting gut health.
As Dr Rossi explains, physical activity improves blood flow to the digestive tract and helps us keep our bowels regular, which means the food passing through our gut is regularly replenished. “The gut is actually a muscle,” she says, “so moving around can help keep the food pumping through and replenishing that nutrient supply to your microbes, which keeps them well fed and satisfied.”
4. She cut back on alcohol
As much as we might enjoy the occasional tipple, alcohol is known to make the gut more permeable, or “leaky”. One of the roles of the gut is to act as a kind of gatekeeper, dictating what can pass through your intestinal lining into your blood system. “It acts as a barrier,” explains Dr Rossi. “But when you have too much alcohol, that barrier becomes permeable, allowing things that shouldn’t pass from your gut into your blood system to get through, resulting in an inflammatory response. In other words, consuming any more than, say, one glass of wine can create low-grade inflammation in your body.”
5. She avoided ‘toxic people’
Having people around you that you don’t get on with can be stressful, and Morera was correct to avoid this dynamic, not just for the sake of her mental health but also the wellbeing of her gut microbiome.
There’s an increasing amount of evidence to suggest that gut health and mental health are linked via the gut-brain axis – a network of nerves, chemical messengers and microbes that constitute your gut microbiome – and that the food you eat can have a significant impact on your mental health. Elevated cortisol levels, often the result of chronic stress, have a negative impact on gut health.
Studies have shown that cortisol can disrupt the gut microbiome and increase intestinal permeability (leaky gut), potentially leading to digestive issues. Stress can also trigger our body’s “fight or flight” mode, which essentially puts the brakes on digestive function, prioritising blood flow to the organs needed for survival. This can lead to a range of unpleasant symptoms, from bloating to constipation.
It may even be the case that some people are literally toxic to have around. “There’s a growing amount of research showing that we share microbes with the people we come into contact with, because we not only have a gut microbiome, we also have a skin microbiome,” says Rossi. “Studies have discovered that housemates – even non-romantic – share microbes. We may even share microbes with people who catch the same Tube or bus. It’s interesting that Morera avoided certain individuals, not only because of the gut-brain axis – so she didn’t get stressed out – but one theory could be that it also meant she was less likely to share ’bad’ microbes from those toxic people.”