The benefits of eating fish have been touted for years. It is a good source of protein, low in fat, and high in omega-3 fatty acids. Now researchers in Sweden have discovered that a protein that occurs naturally in certain types of fish may, when eaten, play a role in preventing Parkinson’s disease (PD).
Parvalbumin, the protein found in high quantities in salmon, red snapper, herring, and cod appears to inhibit the formation of specific complex protein structures in the human brain. Parvalbumin has the ability to form an amyloid structure (folded proteins that stick together) and join with alpha-synuclein proteins. The parvalbumin uses up, or “scavenges”, the alpha-synuclein so that they are not available to build up or clump, which contributes to the development of Parkinson’s, according to Pernilla Wittung-Stafshede, Professor and Head of the Chemical Biology division at Chalmers, lead author on the study.1
Parkinson’s disease is a neurodegenerative disorder with motor and non-motor symptoms. Alpha-synuclein, sometimes called the Parkinson’s protein, has a critical role in the development of the disease. The build-up of alpha-synuclein proteins results in the deterioration of dopamine-producing cells in the substantia nigra area of the brain.2
What is the link?
Proteins are composed of folded amino acid chains that each has a specific job. If the proteins fold incorrectly, they can get caught up with other proteins and clump together. These aggregated proteins, called amyloids, can interfere with the function of certain brain cells and cause certain neurological conditions.3 In Parkinson’s, we understand that the alpha synulein clumps together forming plaques that interfere with neuron messaging, eventually causing the death of certain brain cells.
Increasing fish in your diet could improve brain health
The measured benefits of eating fish have been unsubstantiated in the scientific community. Now, researchers have developed more substantial support for the link between consumption of fish and better long-term cardiovascular and neurological health. The parvalbumin protein is present in many species of fish, and in higher quantities in certain red fish and herrings. According to Nathalie Scheers, an assistant professor at the Chalmers University of Technology, levels of parvalbumin vary greatly throughout the year.4 Fish are more nutritious at the end of the summer. When the fish have been exposed to the sun they have higher levels of the beneficial protein due to increased metabolic activity. Thus, timing the increase in fish consumption to late summer and fall could be even more beneficial to human health and a way to fight off Parkinson’s disease.1,3 The study demonstrated that parvalbumin can enter the bloodstream after digestion in the gut and thus make its way to the brain. There are theories that Parkinson’s may develop initially in the gut (gastrointestinal tract) and then spread to the brain.
Eating fish has been advertised and promoted for improving long-term health. Population studies have shown a correlation between certain diets, like those consumed in the Mediterranean and Japan, with a lower incidence of Parkinson’s disease and other neurodegenerative conditions. These places, surrounded by water, eat a diet rich with fish; likely to have a therapeutic effect.
Parallels to other neurodegenerative diseases
The findings from Sweden related to PD may have implications for other neurodegenerative conditions. Like Parkinson’s, Alzheimer’s, ALS, and Huntington’s disease have no known cures and also involve a build-up of amyloid structures interfering with normal brain function.4 Available drugs only treat the symptoms of these conditions. These diseases generally affect an aging population, and people around the world are living longer. If something as simple as a diet of eating more fish may reduce the aggregation of amyloid formations in the brain, then it is possible that PD could be prevented or delayed. Eating fish could also be positive for general health and for addressing age-related dementia and cognitive decline.2
Lardieri, A. Study: Eating Fish Could Prevent Parkinson's Disease. Published April 23, 2018. https://www.usnews.com/news/health-care-news/articles/2018-04-23/study-eating-fish-could-prevent-parkinsons-disease. Accessed online July 31, 2018.
Werner T, Kumar R, Horvath I, et al. Abundant fish protein inhibits α-synuclein amyloid formation. Sci Rep. 2018;8(1):5465. Published April 3, 2018. https://www.nature.com/articles/s41598-018-23850-0". Accessed online July 31, 2018.
Eating more fish could prevent Parkinson's disease. Chalmers University of Technology
Published April 23, 2018. https://www.sciencedaily.com/releases/2018/04/180423085420.htm. Accessed online July 31, 2018.
Worth, J. Eating fish could prevent Parkinson’s disease. Published May 3, 2018. https://www.chalmers.se/en/departments/bio/news/Pages/Eating-fish-could-prevent-Parkinsons-disease.aspx. Accessed online July 31, 2018.