Healthy Diet May Lower Risk of Relapse After 1st Myelin Attack, Study Suggests
A “prudent” diet rich in fresh fruit, non-fried fish, whole grains, vegetables, and nuts may lower the likelihood of a relapse in people with a first demyelinating event, a major risk factor for multiple sclerosis (MS), a study in Australia suggests.
While the researchers did not find a strong link between such a healthy diet and conversion from clinically isolated syndrome (CIS) to MS, their findings suggest this diet choice may help to prevent clinical progression.
The study, “High Prudent diet factor score predicts lower relapse hazard in early multiple sclerosis,” was published in the Multiple Sclerosis Journal.
Increasing evidence suggests that adopting a healthy diet may lower the risk of MS onset or its progression. However, most studies have focused on specific foods and nutrients, disregarding the potential influence of a person’s total diet, and the food combinations making up meals.
A case-controlled study in almost 700 people, called the Australian Multi-center Study of Environment and Immune Function or AusImmune study, evaluated the effects of dietary patterns, instead of single foods or nutrients, on the risk of a demyelinating event — which marks myelin damage, a classic first MS symptom.
AusImmune data, collected between 2003 and 2006, showed that people who ate a healthy diet — high in poultry, fish, eggs, vegetables, and legumes — were less likely to have such an event and be diagnosed with MS.
However, the potential association between dietary patterns and MS progression remains to be explored.
To fill this gap, researchers in Australia analyzed five-year data from the AusImmune Longitudinal (AusLong) study, which is following AusImmune’s participants over time and investigating risk factors for early MS progression in those with a first demyelinating event.
AusLong started following 279 people (214 women and 65 men) with a first demyelinating event, including 170 diagnosed with CIS, in 2009. Most participants reported little physical activity, and more than half were overweight or obese.
They were asked to complete a food frequency questionnaire concerning dietary habits at AusLong’s start (a baseline measure) and again five years later. A total of 96% of participants responded to the questionnaire either at baseline or years later, and 209 completed both questionnaires.
Three major dietary patterns were identified: a healthy “prudent” diet, or one high in fresh fruit, non-fried fish, whole grains, nuts, and vegetables, including leafy vegetables; a “high-vegetable” diet, or one high in yellow/red and cruciferous vegetables, legumes, potatoes and sauce; and a “mixed” diet that was higher in poultry, red and processed meat, and alcohol intake.
Prudent and high-vegetable diets associated more strongly with healthy nutrients, while the mixed diet linked more with unhealthy nutrients. A prudent diet was more frequently found among older and more physically active people, and less frequently among overweight participants. The mixed diet was significantly more common among ex- and current smokers, and less common among those who were not employed.
Notably, over the five years of follow-up, there was little change in dietary patterns — except among obese participants, who were significantly more likely to move to a prudent diet.
To minimize disease-related influences on diet choices and on outcomes, researchers also evaluated diet only in those with a CIS diagnosis, looking for a possible link between diet patterns and MS conversion and relapse.
Most CIS patients — 94% of 170 — completed either the first baseline food questionnaire or the later one; 128 completed both. Their dietary patterns and changes were not significantly distinct from the entire study group.
Conversion from CIS to MS was defined as the occurrence of a second clinical demyelinating event — found in 96.6% of the cases — or MRI evidence of a new lesion (3.4% of cases). All diagnosed relapses, including the first post-CIS relapse defining MS conversion and subsequent events, were included in relapse analyses.
Results showed the healthier, “prudent” diet was associated with a 46% lower relapse risk. Patients adopting a prudent diet also showed a trend toward a lower subsequent risk of MS conversion, but this association was not statistically significant.
“Prudent diet factor score above the median was prospectively associated with lower relapse risk in the 5 years following the first clinical demyelinating event,” the researchers wrote.
But, “no baseline diet factor scores were associated with MS conversion” risk, they added.
While researchers had hoped for a similar association with both MS conversion and relapse, they suggested that the healthiest diet might have a long-term accumulated benefit against the inflammatory processes underlying myelin loss. However, it was not enough to prevent the second demyelinating event that marks MS conversion.
These findings suggest “a potential point of intervention whereby a better quality of diet may be beneficial in reducing clinical progression,” the researchers wrote.
Further research, they added, is necessary to clarity the role of dietary choices and patterns in both MS onset and disease progression.