DHA (Omega-3)
DHA is essential for brain development and maintenance. Observational studies consistently link higher omega-3 intake to reduced cognitive decline risk. However, RCT results are mixed: a 2012 Cochrane review found no benefit of omega-3 supplementation for preventing cognitive decline in healthy elderly. More targeted research (Yurko-Mauro et al., 2010) showed 900mg DHA/day improved episodic memory in age-related cognitive decline. Benefits are most consistent in populations with low baseline omega-3 status and existing cognitive concerns.
作用機序
Docosahexaenoic acid (DHA) is the primary structural omega-3 fatty acid in the brain, constituting ~40% of polyunsaturated fatty acids in neuronal membranes. DHA maintains membrane fluidity, enabling proper receptor function, ion channel activity, and synaptic vesicle dynamics. It also resolves neuroinflammation via specialised pro-resolving mediators (SPMs) and supports BDNF (brain-derived neurotrophic factor) expression for neuroplasticity.
臨床エビデンスの概要
DHA is essential for brain development and maintenance. Observational studies consistently link higher omega-3 intake to reduced cognitive decline risk. However, RCT results are mixed: a 2012 Cochrane review found no benefit of omega-3 supplementation for preventing cognitive decline in healthy elderly. More targeted research (Yurko-Mauro et al., 2010) showed 900mg DHA/day improved episodic memory in age-related cognitive decline. Benefits are most consistent in populations with low baseline omega-3 status and existing cognitive concerns.
ヒト効果マトリクス
Based on human clinical trials only. Animal and in-vitro data excluded.
| 効果 | エビデンス | 効果の大きさ | 研究数 |
|---|---|---|---|
| Memory (Age-Related Decline) | moderate | 中 | 10 |
| Memory (Healthy Adults) | mixed | 小 | 8 |
| Mood & Depression | moderate | 小 | 15 |
| Brain Structure Preservation | moderate | 中 | 6 |
Evidence key: Strong = multiple consistent RCTs · Moderate = smaller/fewer RCTs · Preliminary = early trials or small n · Mixed = conflicting results
実証された効果
- Neuronal membrane integrity
- Reduced neuroinflammation
- Supports BDNF for neuroplasticity
- Cardiovascular co-benefits
副作用と注意事項
- Fishy aftertaste or burps
- Mild GI discomfort at high doses
- Potential blood-thinning effect at very high doses (>3g/day)
- Generally very well tolerated
摂取方法
スタッキングの推奨
DHA (Omega-3)と相性の良い成分とその理由。
DHA provides the structural fat for membranes; PS is the phospholipid that organises membrane architecture. Together they provide comprehensive neuronal membrane support.
DHA maintains membrane integrity while Lion's Mane stimulates NGF for neuroplasticity. Foundational + growth-oriented brain support.
Citicoline provides choline for membrane phospholipid synthesis; DHA provides the fatty acid substrate. Together they supply the raw materials for brain cell membrane repair.
よくある質問
DHA vs EPA — which matters more for brain health?
DHA is the structural omega-3 in brain membranes (~40% of brain PUFA), making it more directly relevant to cognitive function. EPA is more potent as an anti-inflammatory and shows stronger effects for mood/depression. For brain health, prioritise DHA (aim for 500mg+ DHA specifically). For mood support, prioritise EPA. Most quality supplements provide both.
Can I get enough DHA from diet alone?
If you eat fatty fish (salmon, mackerel, sardines) 2-3 times per week, you likely get sufficient DHA. Most people in Western diets consume far below optimal levels. Vegetarians and vegans are particularly at risk for deficiency — algal DHA supplements are the solution. A blood test (Omega-3 Index) can measure your actual status.
Is fish oil or algal oil better?
Chemically equivalent. Algal-sourced DHA is identical to fish-sourced DHA. Algal oil avoids mercury/heavy metal concerns and is suitable for vegetarians. Fish oil provides a natural DHA+EPA ratio. Neither is objectively superior — choose based on dietary preference and quality of the specific product.
How long before I notice cognitive effects?
DHA works by rebuilding membrane composition, which is a slow process. Most RCTs showing cognitive benefits ran for 12-24 weeks. You will not feel an acute effect like caffeine or L-theanine. Think of DHA as a long-term infrastructure investment, not a performance supplement.