Health and Nutrition

Between nature and the laboratory: food that heals and food that causes illness

Investing in independent research, strengthening training in universities and promoting prevention in schools by encouraging the consumption of natural foods: these are the priorities for reducing the impact on diseases

by Antonio Gasbarrini *, Riccardo Fargione **

19 October 2026

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4' min read

Translated by AI

Versione italiana

4' min read

Translated by AI

Versione italiana

For much of the twentieth century, medicine viewed food primarily in quantitative terms: calories, macronutrients, and deficiencies to be corrected. Today we know that this perspective is not enough. Food is a set of biological signals that interacts with our bodies every day. The primary participant in this dialogue is the gut microbiota – the ecosystem of trillions of microorganisms that inhabit our gut and help regulate our metabolism, immune system and even the gut-brain axis.

What we put on our plates alters the composition and functions of this ecosystem within a matter of days. It affects the integrity of the gut barrier and, through this, the level of low-grade chronic inflammation that the international literature refers to as ‘meta-inflammation’. It is a silent inflammation, which causes no symptoms for years but forms a common ground for many of the major diseases of our time: obesity, type 2 diabetes, non-alcoholic fatty liver disease, cardiovascular diseases and certain forms of cancer. This is where the line is drawn between food that heals and food that causes illness.

The figures

The stakes are enormous, including in economic terms. Chronic non-communicable diseases cause 43 million deaths worldwide every year and, according to the WHO, up to 80 per cent of these conditions could be prevented by addressing modifiable risk factors, including diet. In addition to the social cost, there is also an economic cost. The OECD estimates that, over the coming decades, diseases linked to being overweight will account for an average of 8.4 per cent of member countries’ healthcare expenditure, with measurable effects on productivity and growth as well. Being overweight accounts for around 70 per cent of the costs of treating diabetes and almost a quarter of those associated with cardiovascular diseases. For a country with a long life expectancy such as ours, dietary prevention is one of the most effective ways of ensuring the sustainability of the National Health Service.

The Mediterranean Diet

The Mediterranean diet, recognised by UNESCO as an Intangible Cultural Heritage of Humanity, is one of the most widely studied dietary patterns in the world. It is based primarily on minimally processed cereals, pulses, vegetables, fruit, extra virgin olive oil and fish. It is rich in fibre and plant compounds that the gut microbiota converts into anti-inflammatory molecules, such as short-chain fatty acids. It is no coincidence that it is consistently linked to a lower risk of chronic diseases and mortality.

Ultra-processed foods

At the opposite end of the spectrum are ultra-processed foods. These are not traditionally processed foods, such as bread, pasta or cheese, but industrial products ‘formulated’ using additives such as emulsifiers, sweeteners, colourings and flavour enhancers. The evidence has grown rapidly. A comprehensive review published in the BMJ, based on data from nearly ten million people, linked high consumption of ultra-processed foods to 32 adverse health outcomes. The evidence is strongest for cardiovascular mortality, type 2 diabetes, and anxiety and mood disorders.

Some commonly used emulsifiers have also been shown to alter the composition of the microbiota and the mucus layer that protects the intestinal wall. Similar findings have also been observed for certain sweeteners. It must be made clear: authorised additives are assessed by the European authorities and considered safe within the specified limits. However, scientific understanding is evolving, and these findings warrant further investigation, particularly with regard to cumulative and long-term exposure.

‘Early-onset’ diseases

Meanwhile, epidemiological data show that conditions once typical of older age are appearing at an increasingly early age. This is the case with colorectal cancer in people under the age of fifty, which is on the rise in many countries, and with type 2 diabetes in young people. The causes are certainly multifactorial, but diet and the gut microbiota are among the hypotheses most extensively studied by the international scientific community.

New technologies

On another level are foods derived from cell cultures and proteins produced through precision fermentation. This is a rapidly developing technological frontier, which is attracting significant investment and raising legitimate scientific questions.

One of these concerns the food matrix. A food is not simply the sum of its molecules. The way in which proteins, fats, fibre and micronutrients are organised affects its digestion, absorption and interaction with the microbiota. Reproducing a single component is not the same as reproducing the food in its entirety.

The necessary caution

In recent days, at the Ministry of Agriculture, Food Sovereignty and Forestry, the Catholic University (Piacenza campus) presented data that help shed light on certain aspects of these production methods that have as yet been little explored. The analyses indicate significant nutritional differences compared with the reference foods. They also show that, under current production conditions, the environmental impact may be considerably higher than that of the production methods they are intended to emulate, largely due to the high energy requirements of the processes.

These are factors that call for caution, not a closed-minded approach. European legislation on novel foods already provides for a scientific safety assessment prior to placing them on the market, but alongside this it would be useful to have studies focusing on medium- and long-term health effects, including those on the microbiota, which are rarely taken into account at present. The precautionary principle is not a barrier to innovation, but rather the condition under which innovation can win the trust of the public.

Investing in research

The available evidence already points to a clear way forward. The first step is to invest in independent, long-term nutritional research, which is currently underfunded relative to its potential impact on public health. The second is to strengthen training in clinical nutrition within medical degree programmes and specialist training courses, so that doctors can use food as a tool for prevention and treatment. The third is to permanently integrate nutrition and food into prevention policies, starting with schools, whilst promoting the role of agriculture and natural foods.

This is the approach that the Aletheia Foundation is pursuing in collaboration with healthcare and research institutions, in accordance with the scientific method. The aim is to build bridges between the public, the healthcare sector and the agricultural sector. Restoring real food to its rightful central role means making nutrition, once again, our foremost ally in good health.

* Scientific Director, A. Gemelli IRCCS University Polyclinic Foundation;
Professor of Internal Medicine, Catholic University of the Sacred Heart
** Director, Aletheia Foundation