Omega-3 fatty acids are a family of polyunsaturated fats that are important for the body’s normal functioning. They are part of cell membranes and are involved in processes related to the heart, brain, blood vessels, and immune system.
The main types are ALA (alpha-linolenic acid), EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid). ALA is found mainly in plant foods, while EPA and DHA are found primarily in fish and seafood.
Despite the popularity of fish oil supplements, not everyone needs to take omega-3 supplements. The benefits are better established in certain situations, particularly for lowering high triglyceride levels.
What is omega-3 used for?
EPA and DHA are involved in several functions in the body and may affect:
- triglyceride levels;
- blood vessel function;
- blood pressure;
- heart rate;
- inflammatory processes;
- heart and brain function.
These effects depend on the dose and individual characteristics. In addition, physiological effects do not necessarily mean that omega-3 supplements prevent disease.
What are the benefits of omega-3?
Does omega-3 lower triglycerides?
Yes. This is one of the best-established effects of omega-3 fatty acids.
High doses of EPA and/or DHA, generally between 3 and 4 grams per day, can reduce triglyceride levels by approximately 25% to 50%.
However, the doses used to treat high triglycerides are higher than those found in many over-the-counter supplements. For this reason, treatment should be guided by a healthcare professional.
Does omega-3 protect the heart?
Omega-3 fatty acids have several potentially beneficial effects on the cardiovascular system, but studies on the prevention of heart attacks, stroke, and cardiovascular death have produced mixed results.
In the VITAL trial, which followed 25,871 adults without known cardiovascular disease, 1 gram of omega-3 per day did not significantly reduce the primary cardiovascular outcome.
Therefore, it is not correct to say that everyone should take omega-3 supplements to protect their heart.
Can omega-3 help lower blood pressure?
EPA and DHA may produce a small reduction in blood pressure. In an analysis of 70 studies, the average reduction was approximately 1.5 mmHg in systolic blood pressure and 1 mmHg in diastolic blood pressure. The effect was greater in people with untreated hypertension.
However, omega-3 supplements should not replace medications or other measures recommended to control blood pressure.
Does omega-3 improve memory?
DHA is important for the membranes of brain cells, but this does not mean that omega-3 supplements prevent dementia or improve memory.
Current evidence on omega-3 supplementation for cognition and dementia is not sufficient to recommend it as a general strategy for dementia prevention.
What foods are high in omega-3?
Diet is one of the main ways to obtain omega-3 fatty acids.
Sources of EPA and DHA
Fish and seafood are the main dietary sources of EPA and DHA, especially:
- salmon;
- sardines;
- herring;
- mackerel;
- trout;
- tuna.
Sources of ALA
ALA is found mainly in plant-based foods, including:
- flaxseed;
- chia seeds;
- walnuts;
- flaxseed oil;
- soybean oil;
- canola oil.
The body can convert ALA into EPA and DHA, but this conversion is limited.
Is it better to eat fish or take omega-3 supplements?
For most people, it is preferable to prioritize a healthy and varied diet.
For example, a 1-gram fish oil capsule may contain only 200 to 400 mg of EPA and DHA, depending on the formulation. Therefore, when choosing a supplement, it is important to check the amount of EPA and DHA rather than looking only at the total amount of fish oil.
Do all older adults need to take omega-3?
No.
Age alone is not an indication for omega-3 supplementation. Available data do not show specific problems associated with omega-3 use in older adults, but studies specifically focused on older people also have limitations.
An older adult who follows a balanced diet and regularly consumes omega-3 sources may not need supplements.
The need for supplementation depends on diet, laboratory results, existing health conditions, medications, and the purpose of treatment.
When may omega-3 supplements be recommended?
High-dose omega-3 therapy is mainly used to treat very high triglyceride levels, using specific formulations and under professional supervision.
This is different from taking a standard fish oil capsule every day for cardiovascular prevention.
What are the side effects of omega-3 supplements?
Omega-3 supplements are generally well tolerated, but they may cause:
- fishy taste or aftertaste;
- burping;
- heartburn;
- nausea;
- gas;
- abdominal discomfort;
- diarrhea;
- changes in taste.
These symptoms are more common with higher doses.
Taking some omega-3 formulations with a meal may improve absorption and reduce some digestive symptoms.
Does omega-3 increase the risk of bleeding?
Available evidence indicates that commonly used doses of fish oil do not significantly increase the risk of clinically relevant bleeding.
Nevertheless, people taking anticoagulants or antiplatelet medications should talk to a healthcare professional before starting omega-3 supplements.
Can omega-3 cause atrial fibrillation?
This is particularly important for older adults.
Although lower doses have not consistently been shown to prevent atrial fibrillation, high doses, particularly 3 to 4 grams per day, may be associated with a small increase in the risk of atrial fibrillation.
For this reason, high doses should not be taken without medical guidance.
What is a safe dose of omega-3?
There is no single dose that is appropriate for everyone.
The FDA recommends that the general population consume no more than 3 grams per day of combined EPA and DHA, including no more than 2 grams from supplements, without professional guidance.
This limit does not mean that 3 grams is a recommended daily dose. Higher doses may be used for specific medical conditions, but they require professional supervision.
Frequently asked questions
Does omega-3 help with weight loss?
No. Omega-3 should not be considered a weight-loss supplement.
Does omega-3 prevent heart attacks?
Study results are inconsistent. It cannot be stated that omega-3 supplementation prevents heart attacks in everyone.
Which food contains the most omega-3?
Fish such as salmon, sardines, herring, and mackerel are good sources of EPA and DHA. Flaxseed, chia seeds, and walnuts are sources of ALA.
Can I take omega-3 with blood thinners?
Do not start supplementation without talking to your doctor or pharmacist. People taking anticoagulants or antiplatelet medications may require monitoring.
Does omega-3 improve memory?
DHA is an important component of brain cell membranes, but there is not enough evidence to recommend omega-3 supplements as a general strategy for preventing dementia.
Conclusion
Omega-3 is an important nutrient, particularly in the forms of EPA, DHA, and ALA. Fish, seeds, nuts, and other foods can provide significant amounts of these fatty acids.
Its best-established effect is the reduction of triglyceride levels at higher doses, while the benefits of supplements for preventing cardiovascular disease in people without a specific indication remain less clear.
For older adults, the main message is simple: getting older does not mean that you need to take omega-3 supplements. Supplementation should be individualized, especially for people with cardiovascular disease, high triglyceride levels, or who take multiple medications.
