A meat-heavy diet is linked to multiple sclerosis (MS) and a gut microbiome with less carbohydrate-digesting bacteria, according to a new study published in the journal eBioMedicine.
The results from 49 participants suggest autoimmune disorders could be correlated with the foods that we eat and changes in the gut ecosystem, leading to higher pro-inflammatory markers in the blood.
“This is the first study using an integrated approach to analyse the interplay between diet, gut microbiome, the immune system and metabolism and their contribution to disease pathogenesis and progression in people with MS,” said Associate Professor and corresponding author Laura Piccio in a statement.
The approach used a complex data analysis method called multi-OMICS, which can highlight relationships between multiple variables – in this case, the immune system, gut bacteria, and MS onset. The team believes that such methods could open doors to the investigation into other diseases that may have various causes.
“It opens a new modality to address future scientific questions by not looking at one individual factor, but at their complex interactions. This approach can lead to the identification of relevant networks that could be manipulated for disease prevention or therapeutic intervention.” Piccio continued.
To test for a correlation, the researchers gathered 49 participants: 24 patients with MS, and 25 healthy controls. Various readings were taken from each, including genome sequencing of the gut microbiome, analysis of inflammatory markers in their blood, and four-day food diaries. Researchers then used advanced analysis techniques to spot correlations between any of the metrics.
In the patients with MS, there were significant correlations between a disrupted immune system-microbiome relationship and the disease, plus changes in the blood metabolome. Specifically, they found increased levels of meat metabolites (the products of eating meat), decreased abundance of certain bacteria in the gut, and a greater level of pro-inflammatory signal molecules in the blood. The changes in gut bacteria were linked with how severe the symptoms of MS were in the patient.
Together, the results suggest a strong link between high consumption of meat and levels of inflammatory markers in the blood, possibly stemming from a disruption in the gut microbiome.
When there was an increase in meat consumption, the gut microbiome was less able to digest carbohydrates from vegetables, and this was seen across both the control and MS groups.
“It is increasingly suggested that meat should be eaten in moderation for several reasons including that it is high in saturated fats and that it can promote the production by the gut bacteria of substances with potentially detrimental effects on our health,” Professor Piccio said.
The research does have a limited sample size and has only identified correlations to date, but such studies highlight the importance of considering multiple variables in the study of complex diseases.