Evidence suggests that oxidative stress may also play a role in the pathophysiology of neurodegenerative diseases. Increases in the production of reactive oxygen species have been shown to influence mitochondrial activity, neurotransmission, and cellular metabolism. Altered cellular metabolism has been linked to increases in the accumulation of amyloid and tau proteins. Recent epidemiologic studies have associated lower rates of certain neurodegenerative diseases with a higher dietary intake of nutrients that support antioxidative status. A recent study explored the potential impact of fish oil on age-related changes linked to certain neurodegenerative diseases. 

Fish oil contains polyunsaturated fatty acids (PUFAs), which are fatty acids with two or more carbon-carbon double bonds. Their nomenclature is based on the position of where the first double bond is located. Omega-3 (n-3) PUFAs, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha-linolenic acid (ALA) have been shown to support a healthy response to inflammation and oxidative stress. Alternatively, omega-6 (n-6) PUFAs participate in pro-inflammatory processes in the body. Typical Western diets contain a higher amount of n-6 than n-3 PUFAs. The brain has been shown to be particularly affected by oxidative stress due to its relatively high consumption of oxygen and abundance of PUFAs. 

Torres-Mendoza and colleagues recently published a clinical trial involving the administration of fish oil on markers related to oxidative stress and the progression of certain neurodegenerative diseases. This randomized, double-blind, placebo-controlled clinical trial included 20 individuals with a history of cognitive decline who did not currently consume supplements to support antioxidative status. 

The treatment group received 450 mg of EPA and 1 g of DHA daily for 1 year. Improvements in certain biomarkers related to antioxidative status were observed at months 6 and 12, including significant improvements in catalase activity in the treatment group as compared with a placebo. Study strengths include a relatively long clinical study period and a placebo control. However, more research, particularly with larger sample sizes and more comprehensive assessments of biomarkers related to age-related cognitive changes is needed before clinical conclusions can be made.

Fish oil has been shown to support antioxidative status, a healthy inflammatory response, and brain health. Recent research indicates it may also help cognitive functioning and age-related changes. 

By Colleen Ambrose, ND, MAT