Scientific evidence is becoming increasingly clear: A diet based on real and minimally processed foods helps prevent age-related diseases. But it's not just what we eat that matters. Also, when we do it. In this new installment of the 'Living Better' series, we talk to nutritionist and researcher Marta Garaulet Aza about how to age better.
What role does food play in longevity?
Food is one of the most important modifiable factors in promoting a long and healthy life. However, when we talk about longevity, we shouldn't just think about living longer, but about reaching advanced ages with a good quality of life, maintaining physical, cognitive and emotional health.
Scientific evidence shows that dietary patterns based on minimally processed foods, such as the Mediterranean diet, are associated with a lower risk of cardiovascular disease, type 2 diabetes, obesity and some types of cancer. These are all factors that directly influence life expectancy.
Classic research has shown that "eating little", that is, calorie restriction, increases longevity. However, recent studies in experimental animals have shown that while caloric restriction itself increases longevity by 10%, if this restriction is done at the appropriate times according to circadian rhythms, the average lifespan increases by 35%.
Our studies have shown that it's not just what we eat that matters, but also when we eat. Our bodies function following biological rhythms of approximately 24 hours, and respecting these rhythms through regular eating times and reduced intake during the last hours of the day can promote better metabolism and contribute to healthier aging.
What is the relationship between food and overall well-being?
Nutrition influences virtually all of the body's systems. Nutrients provide the energy and components necessary for the proper functioning of our cells, but they also modulate important processes such as inflammation, immune response, sleep, mood and brain function.
This is why we currently talk about a comprehensive view of nutrition. A healthy diet not only helps prevent disease, but can also improve emotional well-being, cognitive ability, energy levels and sleep quality. Health does not depend on a single food or nutrient, but on the set of habits we maintain day after day.
“A healthy diet not only helps prevent disease, but can also improve emotional well-being and cognitive ability.”
What is the gut-brain axis and why is it generating so much interest?
The gut-brain axis is a bidirectional communication network that connects the digestive system to the central nervous system through nerve, hormonal, immunological and metabolic pathways. Here, the gut microbiota plays a key role by transforming nutrients into biological signals that influence metabolism, inflammation and brain function. These bacteria do not send thoughts to the brain, but produce compounds that the body interprets through the vagus nerve, the immune system, intestinal hormones and various microbial metabolites.
This explains why gut health can influence emotional state, energy or stress response. Much of the body's serotonin is produced in the gut and, although it does not reach the brain directly, it modulates signals related to well-being. Low-grade inflammation or bowel rhythm disturbances can also affect the dopaminergic system, leading to apathy, fatigue or a need for more intense stimuli. Maintaining a diverse microbiota and a healthy gut contributes to the nervous system's balance.
Can the gut influence our food choices?
There is increasing evidence that the relationship between food and the brain is much more complex than we thought. The gut participates in regulating appetite, satiety and food preferences through hormonal and metabolic signals that reach the brain.
Our food choices are also influenced by psychological, social, cultural and environmental factors. Therefore, we cannot attribute dietary decisions exclusively to the microbiota or the gut. What's most important is understanding that there is a continuous interaction between what we eat, the microorganisms that live in our gut and the signals our brain receives.
In an era where there is much talk about specific nutrients, why is it important to focus on real food?
For much of the 20th century, nutrition focused on preventing deficiency diseases, that is, those caused by a lack of specific nutrients. It was a time with less access to food, and that's why it was essential to avoid deficiencies such as scurvy due to lack of vitamin C, rickets due to vitamin D deficiency or anemia due to lack of iron.
Today we live in a very different context: a society of excess, where the problem is not usually just the quantity of nutrients, but the quality, origin and degree of processing of what we eat. Therefore, nutrition has evolved from a view based on isolated nutrients to one focused on foods and eating patterns.
What do you think is the main nutritional challenge of the coming decades?
One of the biggest challenges will be adapting our nutritional recommendations to the individual characteristics of each person. The same diet does not produce exactly the same effects in all individuals. Factors such as genetics, individual chronotype, eating schedules, sleep, physical activity, gut microbiota and age can modify the response to food.
We are moving towards increasingly personalized nutrition, but without losing sight of a fundamental message: the foundation remains a balanced diet based on minimally processed foods, accompanied by healthy lifestyle habits and adapted to each person's biological rhythms. The Mediterranean diet, rich in legumes, whole grains, fruits, vegetables, fish and olive oil, is a model to follow, especially in Mediterranean countries like ours, where this type of diet is deeply ingrained in our culture.