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Omega-3, found in foods such as fish and walnuts, may be beneficial for people with ALS, a progressive, incurable disease. Ingrid Bertens/Stocksy
  • Omega-3 fatty acids are known to have a variety of health benefits.
  • Researchers from Harvard University have now found that people with ALS who eat foods high in omega-3 fatty acids may have a slower physical decline and extended survival rate.
  • Scientists also found that omega-6 fatty acid was associated with a lower risk of death among study participants.

For many years, research has shown omega-3 fatty acids to bring a variety of health benefits.

Previous studies show that these healthy fats found in seafood and some plants could help protect against cardiovascular disease, age-related macular degeneration, metabolic syndrome, autoimmune diseases, and Alzheimer’s disease.

Now, researchers from Harvard University have found that people with amyotrophic lateral sclerosis (ALS) — an incurable progressive neurological disease — who eat foods high in omega-3 fatty acids may have a slower physical decline and extended survival rate.

The researchers also found consumer omega-6 fatty acid was also associated with a lower risk of death among study participants.

This study was recently published in Neurology, the medical journal of the American Academy of Neurology.

ALS — also known as Lou Gehrig’s disease — is a disease affecting the body’s central nervous system, mainly the nerve cells in the brain and spinal cord.

As ALS affects the neurons needed for movement, over time a person loses their ability to control their leg, arm, and facial movements. In extreme cases, people with ALS may eventually not be able to speak or eat.

According to the ALS Association, “[w]ithin a population of 100,000 people, there are two new ALS cases each year.”

Most people who develop ALS are between the ages of 40 and 70, and it is more common in men.

Symptoms of ALS include:

Researchers still do not know exactly what causes ALS, but they believe genetics and environmental risk factors may play a role.

There is currently no cure for ALS. Some treatments are available to help alleviate symptoms.

The average life expectancy for someone with ALS is often between 2 to 5 years, with some people living longer.

According to Dr. Kjetil Bjornevik, assistant professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health at Harvard University, and lead author of this study, he and his research team decided to study the link between diet and ALS as they were interested in identifying modifiable risk factors for neurological disorders, such as dietary factors.

“We have previously conducted studies that have shown that a diet high in omega-3 fatty acids, particularly alpha-linolenic acid, may decrease the risk of developing ALS,” he told Medical News Today.

“We were therefore interested in examining whether a diet high in these fatty acids is also associated with slower disease progression in individuals already diagnosed with ALS,” he added.

This is not the first time researchers have examined the effect of essential fatty acids on ALS. A study in 2017 found that a balance of both omega-3 and omega-6 fatty acids is important for preserving motor neuron function in ALS.

And research published in 2019 reported omega-3 fatty acids could be used to produce medications for treating neurodegenerative disorders.

In this study, Dr. Bjornevik and his team recruited 449 people who have ALS with an average age of 58 years. Study participants were followed over 18 months. During that time, 126 or 28% of participants passed away.

Researchers examined the levels of omega-3 fatty acids in the blood of each participant. And all participants received scores on 12 physical functions — including swallowing, chewing, and speaking — between zero and 48, with higher scores equaling greater function.

Upon analysis, scientists found that participants with the highest amount of the type of omega-3 fatty acid called alpha-linolenic acid had an average score of 38.3 at the start of the study. Those with the lowest amount had an average score of 37.6.

Additionally, the research team found only 21 of the 126 deaths occurred in the group with the most alpha-linolenic acid in their system, compared to 37 deaths that happened in the lowest omega-3 fatty acid group.

After adjusting for age, sex, and ethnicity, Dr. Bjornevik and his team reported study participants with the highest amount of alpha-linolenic acid had a 50% lower risk of death during the study, compared to those in the lowest amount group.

“Our findings suggest that specific omega-3 fatty acids, such as alpha-linolenic acid, may exert a favorable effect on people with ALS,” Dr. Bjornevik said.

“However, randomized clinical trials are necessary to establish whether supplementation with this fatty acid is beneficial,” he cautioned.

Also during the study, the research team correlated an omega-6 fatty acid called linoleic acid to a lower risk of death during the study timeframe.

“Linoleic acid, the omega-6 fatty acid associated with a lower risk of death in our study, is also an essential fatty acid that can only be obtained through diet,” Dr. Bjornevik explained.

“However, whether and how this fatty acid has beneficial effects in people with ALS is less clear. Our article primarily focused on omega-3 fatty acids, as our previous studies found these fatty acids to be associated with a reduced risk of developing ALS,” the researcher noted.

MNT also spoke with Dr. Stephen Johnson, neuromuscular disease specialist at the Mayo Clinic, about this study.

“I am always hopeful for the next breakthrough that might slow down, stop, or even reverse ALS disease progression, so I read the article with great interest and cautious optimism,” he commented.

“The results of the study are intriguing and pave the way for additional studies, which must take place to more definitively answer the question: Do certain fatty acids slow down ALS disease progression and extend life? Right now, we have an association and must next do our due diligence to better establish whether this association is reproducible in the context of a more rigorous scientific study.”

– Dr. Stephen Johnson

For the next steps in this research, Dr. Johnson said he would like to see a large prospective phase 2/3, double-blind, randomized, placebo-controlled trial evaluating the identified potentially beneficial fatty acids.

“This trial should, in addition to measuring longevity and participant function, pay particularly close attention to participant diet, medications/supplements, and any potential confounders,” he continued. “However, it is likely a phase 1 clinical trial will need to take place first.”

“By taking these next steps, just as we would with any pharmaceutical medication, we can determine whether the association is more than just an association and whether certain fatty acid dietary supplementation should be added to the standard of care for people with ALS,” Dr. Johnson added.

Omega-3 and omega-6 are two categories of essential fatty acids.

As the name implies, essential fatty acids are required for the body to function properly. However, the body cannot make essential fatty acids, making it necessary to acquire them through foods.

The body uses essential fatty acids to:

Foods rich in omega-3 fatty acids include:

And foods for obtaining omega-6 fatty acids are: