In particular, alpha-linolenic acid (ALA) – an omega-3 found in foods including flaxseeds, walnuts, and chia, canola, and soybean oils – was linked to longer survival and slower functional decline in ALS patients, according to the study, which was led by the Harvard TH Chan School of Public Health.
“Prior findings from our research group have shown that a diet high in ALA and increased blood levels of this fatty acid may decrease the risk of developing ALS,” said lead author Kjetil Bjornevik, assistant professor of epidemiology and nutrition.
“In this study, we found that among people living with ALS, higher blood levels of ALA were also associated with a slower disease progression and a lower risk of death within the study period.
“These findings, along with our previous research, suggest that this fatty acid may have neuroprotective effects that could benefit people with ALS.”
ALS: An incurable progressive disease
ALS is a rare neurodegenerative disease that affects motor neurons – the nerve cells in the brain and spinal cord that control voluntary muscle movement, governing actions such as chewing, walking, and talking. The disease is progressive, meaning the symptoms get worse over time, and there is no effective treatment to reverse its progression.
While medication may be used to manage ALS symptoms, there is currently no cure for the disease, meaning research into alternatives is valuable.
The researchers examined 449 people living with ALS, testing them for symptom severity and disease progression before assigning scores between 0 and 40, with higher scores indicating less severe symptoms. They then measured the levels of omega-3 fatty acids in participants’ blood and split them into four groups accordingly. Follow-up to track the group’s physical functionality and survival was carried out after 18 months.
ALA is the alpha of omega-3s
ALA demonstrated the most benefits of all omega-3s, as it was most strongly linked to slower decline and increased survival, according to the study, which was published in the journal Neurology.
Of the 126 participants who died within the follow-up period, 33% belonged to the group with the lowest ALA levels, while 19% belonged to the group with the highest ALA levels.
Adjusting for confounding factors such as age, sex, ethnicity, BMI, symptom duration, and family history of ALS, the researchers calculated that the participants with the highest levels of ALA had a 50% lower risk of dying during the study period compared with those who had the lowest levels of ALA.
‘Intriguing’ link between diet and ALS
Two other fatty acids were also associated with increased survival: eicosapentaenoic acid, another omega-3 found in fatty fish and fish oil, and linoleic acid, an omega-6 found in vegetable oils, nuts, and seeds.
“The link our study found between diet and ALS is intriguing,” said senior author Alberto Ascherio, professor of epidemiology and nutrition. ”We are now reaching out to clinical investigators to promote a randomised trial to determine whether ALA is beneficial in people with ALS.
“Obtaining funding will be challenging, because ALA is not a patentable drug, but we hope to get it done.”