Perhaps you are familiar with the saying “fish is brain food.” My mother used to tell me this to encourage me to eat my fish sticks. She was pretty smart because there is scientific evidence behind that adage.
What is so special about fish that it can nourish your brain? The answer is the omega-3 fatty acids present in fish, the most prominent of which are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which have been shown to possess an ability to support and promote brain function. Another omega-3, called alpha-linolenic acid (ALA), is found in several foods (but not fish).
Read about omega-3s, the smart choice for your brain
Although the human body can make DHA and EPA from ALA, the conversion process is far from efficient and so fish and fish oil are considered by most experts to be the best sources of these essential fatty acids. Both EPA and DHA are integral components of cell membranes and also have powerful anti-inflammatory abilities which are key not only for the brain but for the heart and human development as well.
Where can you find omega-3 fatty acids?
You need look no farther than cold water fatty fish, such as anchovies, herring, sardines, tuna, and salmon as rich sources of EPA and DHA. If fish is not your cup of tea, then fish oil supplements can be substituted instead. In fact, even if you do eat fish, few people consume the two or more servings per week that is recommended, so a supplement can be an easy way to boost your intake.
If you want to rely on ALA for your omega-3 intake, this is a challenge. ALA is found in foods such as canola oil, chia seeds, flaxseeds, soybeans, soybean oil, and walnuts. (Often canola and soybeans are genetically modified, so if you choose these sources make sure they are organic.) An omega-3 supplement is likely needed, but if you do not consume fish or fish oil, there are a few algae-based EPA and DHA supplements available for vegans and others who do not consume fish or fish products.
Read about what you need to know about the different types of omega-3 fatty acids
Experts vary on their recommendations for intake of EPA and DHA from omega-3 supplements. A suggested daily dose is 1,000 to 2,000 mg of omega-3 fatty acids from fish oil or a comparable omega-3 supplement.
How are omega-3s good for your brain?
Both EPA and especially DHA are important even before an infant emerges from the womb, as they play a crucial role in the development of a baby’s brain. But the benefits keep on coming. For example:
- Intake of omega-3s as fish or fish oil among pregnant women has been correlated with higher test scores of intelligence and brain function in early childhood of their offspring.
- The fatty acids in cell membranes of brain cells are responsible for preserving cell membrane health and assisting with intercellular communication.
- Low levels of omega-3 fatty acids may speed up aging of the brain and contribute to impaired brain function.
- Use of fish oil supplements has been shown to improve brain function in individuals who have mild cognitive impairment or age-related cognitive decline. Some research suggests it is best to start taking omega-3 supplements during the early stages of brain function decline or else they not be as beneficial.
- If you are depressed, fish oil supplements may result in an improvement in depressive symptoms comparable with those achieved when taking antidepressants. Depressed individuals who got the most benefit from taking fish oil were those who were also taking antidepressants and/or those who took fish oil supplements that had high doses of EPA.
What’s the bottom line?
Mom was right: fish—or more accurately, omega-3 fatty acids—is good for your brain. Taking an omega-3 supplement is recommended if you do not eat fish several times a week, and especially if you have mild cognitive decline or have been diagnosed with depression. Talk to a knowledgeable healthcare provider before you begin taking omega-3 supplements. The Food and Drug Administration has determined that 3,000 mg daily is the safe upper limit for supplementation, although the European Food Safety Authority sets their limit at 5,000 mg.
Because fish oil can affect the ability of your blood to clot, you should tell your doctor you are taking these supplements, especially if you are also taking blood thinners or are scheduled for surgery, including dental surgery.
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