There is much scientific evidence linking high consumption of ultra-processed food with an increased risk of cardiovascular and cerebrovascular diseases, metabolic disorders such as obesity and diabetes, some types of cancer and, according to a recent study published in the European Journal of Clinical Nutrition (2023 May;77(5):611-614), also multiple sclerosis.
Ultra-processed food consists of packaged foods that do not contain fresh or real ingredients, but have been made with ingredients that have undergone processes such as hydrogenation or frying of oils, hydrolysis of proteins or refining of flours. These treatments reduce their quality and nutritional properties, resulting in unhealthy products that are high in energy and low in nutrition. In addition, ultra-processed foods, in order to be more attractive, usually have a very high content of additives such as preservatives, colorants, sweeteners, de-foaming agents, emulsifiers, whiteners, bulking agents or flavor enhancers. Ultra-processed foods are for example snacks, sugary drinks, industrial pastries, processed meats, cookies, pizzas or nuggets.
In this study conducted in Australia, the authors have evaluated whether the consumption of ultra-processed food increases the probability of suffering a first diagnosis of clinically isolated syndrome, that is, a first episode of neurological symptoms lasting at least 24 hours caused by inflammation or demyelination of the central nervous system and which usually predicts the development of multiple sclerosis.
The authors analyzed a group of 267 persons affected by a first diagnosis of an isolated clinical syndrome and a control group of 508 healthy persons. Both groups were comparable, i.e., they showed no statistically significant differences with respect to age, gender, area of residence, level of education, body mass index and physical activity. However, a higher percentage of persons affected by a first diagnosis of an clinically isolated syndrome had been smokers and had suffered infectious mononucleosis caused by infection with Epstein Barr virus. Both smoking and Epstein Barr virus infection are considered triggers of multiple sclerosis, so it is not surprising that more people affected by clinically isolated syndrome are or have been smokers and/or have suffered infectious mononucleosis. Regarding the consumption of ultra-processed food, the authors found that this consumption was significantly higher in people affected by a first diagnosis of clinically isolated syndrome than in healthy controls. According to the results of this study, people who consume at least one serving of ultra-processed food per day are 8% more likely to suffer from a clinically isolated syndrome and thus multiple sclerosis.
Ultra-processed food may influence the development of multiple sclerosis indirectly by displacing the consumption of fresh foods such as fruit, vegetables or oily fish rich in vitamins, antioxidants or omega-3 fatty acids with anti-inflammatory and neuroprotective properties. Ultra-processed food may also contribute to the development of multiple sclerosis directly by altering the composition of the gut microbiota, i.e. by inducing dysbiosis and facilitating the spread of bacteria that promote pro-inflammatory responses that contribute to the development of neuroinflammation and neurodegeneration. In addition, ultra-processed food may also contain harmful chemicals that can be detrimental to health.
This is the first study to demonstrate an effect of ultra-processed food on the development of multiple sclerosis, and although it was conducted in people of Caucasian origin and therefore cannot be generalized to other ethnic groups, it highlights the importance of healthy eating and nutritional education for people at risk of developing clinically isolated syndrome or multiple sclerosis.