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Other Names:

Acide Docosahexaénoïque, Acide Gras d’Huile de Poisson, Acide Gras Oméga 3, Acide Gras N-3, Acide Gras W-3, Acido Docosahexaenoico, ADH, DHA, Fish Oil Fatty Acid, N-3 Fatty Acid, Neuromins, Omega 3, Oméga 3, Omega 3 Fatty Acids, Omega-3 Fatty Ac...
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DHA (docosahexaenoic acid) is a fatty acid found in the meat of cold-water fish, including mackerel, herring, tuna, halibut, salmon, cod liver, whale blubber, and seal blubber.

Don’t confuse DHA with EPA (eicosapentaenoic acid). They are both in fish oil, but they are not the same. DHA can be converted into EPA in the body. See separate listings for fish oil and EPA.

DHA is used as a supplement for premature babies and as an ingredient in baby formula during the first four months of life to promote better mental development. This practice probably started because DHA is found naturally in breast milk. DHA is also used in combination with arachidonic acid during the first four to six months of life for this purpose.

DHA is used for treating type 2 diabetes, coronary artery disease (CAD), dementia, and attention deficit-hyperactivity disorder (ADHD).

Some people use DHA is for improving vision, preventing an eye disease called age-related macular degeneration (AMD), preventing and treating depression, and reducing aggressive behavior in people in stressful situations.

DHA is used in combination with eicosapentaenoic acid (EPA) for a variety of conditions, including the prevention and reversal of heart disease, stabilizing heart rhythm, asthma, cancer, painful menstrual periods, hayfever, lung diseases, systemic lupus erythematosus (SLE), and certain kidney diseases. EPA and DHA are also used in combination for high cholesterol, high blood pressure, psoriasis, Raynaud’s syndrome, rheumatoid arthritis, bipolar disorder, certain inflammations of the digestive system (ulcerative colitis) and preventing migraineheadaches in teenagers.

It is also used in combination with evening primrose oil, thyme oil, and vitamin E (Efalex) to improve movement disorders in children with a condition called dyspraxia.

How does it work?

DHA plays a key role in the development of eye and nerve tissues. DHA may also reduce the risk of heart and circulatory disease by decreasing the thickness of the blood and lowering blood levels of triglycerides.

DHA (DOCOSAHEXAENOIC ACID) Uses & Effectiveness What is this?

Possibly Effective for:

  • Reducing the risk of death in people with coronary artery disease, when DHA is consumed as part of the diet.
  • Preventing an eye disease called age-related macular degeneration (AMD), when DHA is consumed as part of the diet.
  • Psoriasis, when given along with EPA intravenously (by IV) by a healthcare provider.

Possibly Ineffective for:

  • Attention deficit-hyperactivity disorder (ADHD). Many children with ADHD have low levels of DHA in their blood. But taking DHA doesn’t seem to improve ADHD symptoms. However, some beginning research suggests that DHA might help children with ADHD become less aggressive and get along better with others.
  • Type 2 diabetes. Taking DHA does not seem to lower blood sugar or cholesterol in people with type 2 diabetes.
  • Depression.

Insufficient Evidence for:

  • Alzheimer’s disease. Some research suggests that getting more DHA from the diet might help to prevent Alzheimer’s disease.
  • High cholesterol and high triglycerides (blood fats). Early evidence suggests that taking 4 grams of DHA daily can reduce triglyceride levels by 20% in men with high triglycerides. DHA does not seem to significantly lower total cholesterol levels or increase “good cholesterol” (high-density lipoprotein (HDL) cholesterol) levels. Unfortunately, DHA might increase “bad cholesterol” (low-density lipoprotein (LDL) cholesterol) by around 8%.
  • Improving infant development. There is some evidence that infants who do not get DHA from breast milk or formula have delayed mental and visual development compared to those who do receive enough DHA. Some researchers reasoned that giving DHA in formula might improve development. But when they tested this theory, study results did not agree. The reason for the differences may be due to the way the studies were designed. For now, experts generally recommend breast-feeding instead of formula-feeding. However, if formula is used, some experts suggest a formula providing at least 0.2% of fats from DHA.
  • Improving night vision in children with dyslexia. Taking DHA seems to improve night vision in children with dyslexia.
  • Improving movement disorders (dyspraxia) in children. Taking DHA in combination with evening primrose oil, thyme oil, and vitamin E (Efalex), seems to improve movement disorders in children with dyspraxia.
  • Depression.
  • Dementia.
  • Improving vision.
  • Reducing aggressive behavior in people under stressful situations.
  • Other conditions.
More evidence is needed to rate DHA for these uses.


DHA is LIKELY SAFE for most people when used appropriately. DHA can cause nausea, intestinal gas, bruising, and prolonged bleeding. Fish oils containing DHA can cause fishy taste, belching, nosebleeds, and loose stools. Taking DHA with meals can often decrease these side effects.

DHA is POSSIBLY UNSAFE when used in large amounts. When used in amounts greater than 3 grams per day, fish oils containing DHA can thin the blood and increase the risk for bleeding.

Special Precautions & Warnings:

Pregnancy and breast-feeding: DHA is LIKELY SAFE when used appropriately during pregnancy and breast-feeding. DHA is commonly used during pregnancy and is an ingredient in some prenatal vitamins. DHA is a normal component of breast milk and is added as a supplement to some infant formulas.

Aspirin-sensitivity: DHA might affect your breathing, if you are sensitive to aspirin.

High blood pressure: DHA can lower blood pressure and could lower blood pressure too much in people who are also taking blood pressure medications. If you have high blood pressure, check with your healthcare provider before taking DHA.

DHA (DOCOSAHEXAENOIC ACID) Interactions What is this?

Moderate Interaction Be cautious with this combination

  • Medications for high blood pressure (Antihypertensive drugs) interacts with DHA (DOCOSAHEXAENOIC ACID)

    DHA can decrease blood pressure. Taking DHA along with medications for high blood pressure might cause you blood pressure to go too low.

    Some medications for high blood pressure include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDiuril), furosemide (Lasix), and many others.

  • Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs) interacts with DHA (DOCOSAHEXAENOIC ACID)

    DHA (docosahexaenoic acid) is often combined with EPA (eicosapentaenoic acid). EPA might slow blood clotting. Taking DHA (docosahexaenoic acid) along with medications that also slow clotting might increase the chances of bruising and bleeding.

    Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.


Experts recommend increasing your daily dietary intake of cold-water fish, including mackerel, herring, tuna, halibut, and salmon.

DHA is usually administered with EPA (eicosapentaenoic acid) as fish oil. A wide range of doses have been used. A typical dose is 5 grams of fish oil containing 169-563 mg of EPA and 72-312 mg of DHA.

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