- Children and adolescents remain the largest consumers of ultra-processed foods, raising concerns about potential long-term health impacts.
- Researchers found higher intake of ultra-processed food in people with childhood-onset MS from the US and Canada.
- Further study is needed to understand whether higher ultra-processed food intake could be an effect, a risk factor or neither in childhood-onset MS, and its impact on health outcomes.
Exploring diet and childhood-onset MS
Multiple sclerosis (MS) is a disease in which the immune system attacks the brain and spinal cord. Although MS is more commonly diagnosed in adults, some people experience their first symptoms during childhood or adolescence, known as childhood-onset MS.
The exact causes of MS are not fully understood. Researchers believe the disease develops through a combination of genetic, environmental, and lifestyle factors. The role of diet has long been considered in MS, influencing both risk factors (adolescent obesity) and health outcomes.
In recent years, researchers have become increasingly interested in ultra-processed foods. These foods are made using industrial processing methods and can contain harmful ingredients designed to improve taste, texture, or shelf life. Examples include sugary drinks, packaged snacks, instant noodles, processed meats, and frozen desserts.
Ultra-processed foods are often high in sugar, unhealthy fats, and calories, while being low in fibre, vitamins, and other important nutrients. They also commonly contain additives, artificial ingredients and chemicals, and exposure to chemicals from heated plastic packaging may affect the gut and immune system. Researchers believe these substances may increase inflammation in the body and affect communication between the gut, brain, and immune system, which could contribute to processes involved in MS onset and ongoing symptoms.
Additionally, ultra-processed foods are designed to be less filling, which may lead people to eat more of them and less healthy foods such as fruits, vegetables, fish, and lean meats that support brain and immune health.
Although research into ultra-processed foods and MS is still in its early stages, findings from adult studies suggest that higher intake of ultra-processed foods is associated with an increased likelihood of experiencing a first neurological event that may lead to an MS diagnosis. Higher consumption of ultra-processed foods has also been linked to more severe MS symptoms. These findings suggest that ultra-processed foods may play a role in processes related to MS development and progression.
Ultra-processed foods make up a substantial part of many children’s and adolescents’ diets around the world. However, little research has examined whether similar patterns exist in children and young people with childhood-onset MS.
What did the researchers do?
The study used data from the Canadian Paediatric Demyelinating Disease Network microbiome study, which included participants recruited from several healthcare centres in Canada and one site in the United States. The team included two MS Australia-funded researchers.
Researchers examined dietary information from 80 children and young people with childhood-onset MS and 46 young people without MS.
Participants completed a questionnaire about foods consumed during the previous week. The researchers then grouped foods according to the NOVA food classification system, which categorises foods based on the level of industrial processing involved in their production.
The team calculated the proportion of each participant’s diet that came from ultra-processed foods and compared the results between the two groups.
They also considered factors such as age, sex, race, region of residence, total energy intake, and body mass index (BMI) when analysing the findings.
What did the researchers find?
The researchers found that, on average, young people with childhood-onset MS consumed a higher proportion of ultra-processed foods than those without MS.
Among participants with childhood-onset MS, ultra-processed foods accounted for a median of 44% of total food intake, compared with 34% among those without MS.
Common ultra-processed food consumed in both groups included fruit drinks, soft drinks, flavoured milk-based drinks, packaged ready meals, and ice cream.
The study found that higher intake of ultra-processed foods was associated with increased odds of having childhood-onset MS.
The researchers also explored whether body weight might help explain the association, since ultra-processed foods have previously been linked with higher BMI. However, they did not find evidence that BMI significantly influenced the relationship observed in this study.
What is the significance of this?
This study contributes to a growing area of research examining how dietary patterns are associated with MS
Because the study compared dietary patterns after participants had already developed MS, it cannot determine whether ultra-processed foods played a role in causing childhood-onset MS. It is possible that living with MS influenced eating habits – that is, people ate more ultra-processed foods after diagnosis.  Studies in adults in Australia have found the reverse – that people are highly motivated to adopt a healthier diet after an MS diagnosis – but the effects of MS diagnosis on children and young people’s diets are not well understood.
In addition, the study was relatively small, and dietary information was based on participants recalling what they had eaten over the previous week.
Importantly, the study does not suggest that eating ultra-processed foods causes MS, nor does it imply that occasional consumption is harmful. MS is a complex condition influenced by many interacting factors, including genetics, environment, and immune function.
The findings highlight the need for further research into how overall dietary patterns may relate to immune health and MS risk over time. Larger and longer-term studies may help clarify whether diet could play a role alongside other known risk factors for childhood-onset MS, or if a diagnosis of childhood-onset MS results in dietary change.
