Omega-3 Fatty Acid
Docosahexaenoic Acid
Also known as: DHA
A key structural component of the brain essential for cognitive function, memory, and long-term brain health.
KÖGN Health grades Docosahexaenoic Acid as A+ (Strong evidence) and rates it 4.5 out of 5.
Last reviewed · June 2026
Primary effects
- Improved memory
- Brain development
- Neuroprotection
How it works
Supports neuronal structure and function, improving communication between brain cells.
Overview
DHA is one of the most critical nutrients for brain health, forming a major part of neuronal membranes. It plays a vital role in cognitive development, maintenance, and ageing. Supplementation is particularly beneficial in individuals with low dietary intake of omega-3s. Its effects are foundational and long-term, rather than immediately noticeable.
The evidence
DHA is the main structural omega-3 fatty acid in brain cell membranes, which is why it is the omega-3 most studied for memory. A 2015 meta-analysis found DHA (alone or with EPA) improved episodic memory in adults with mild memory complaints, with clearer effects above 1 g/day; benefit is smaller in people who already eat oily fish. For mood specifically, EPA appears to matter more than DHA.
How to dose it
Memory studies commonly use around 1 g (1,000 mg) of DHA per day, taken with food. It is often supplied together with EPA in fish or algal oil.
When to take it
Chronic — DHA incorporates into membranes over weeks to months.
Safety & side effects
Well tolerated; the usual effects are a fishy aftertaste or mild reflux. High combined omega-3 doses have a mild blood-thinning effect.
Who should avoid it
Take care with anticoagulant or antiplatelet medication and around surgery. Choose an algal-oil source if you have a fish or shellfish allergy. See the Omega-3 entry for the combined picture.
References
Related ingredients
Graded entries that target the same cognitive goals.
Categories
Draft — the dose, safety and evidence notes on this entry were prepared from the published literature and are pending editorial and clinical review.
Educational information, not medical advice. The evidence grade is KÖGN’s editorial assessment of published research, not a health claim. Speak to a qualified clinician before changing what you take.