Omega-3 fatty acids play an important role in heart and brain health. Since the human body cannot produce these fatty acids or can only produce them to a very limited extent, we must consciously incorporate them into our diet. Some people also take them in the form of dietary supplements. But this can sometimes be dangerous.
Preparations containing omega-3 fatty acids can increase the risk of atrial fibrillation in heart patients, reports the Federal Institute for Risk Assessment (BfR, PDF). Both medicines and dietary supplements such as fish oil capsules can cause this undesirable effect.
Essential fatty acids
Omega-3 fatty acids are vital for us. They play an important role in heart and brain health.
They are also associated with a stronger immune system, a reduction in inflammation, and lower blood pressure and triglycerides, reducing the risk of heart disease and cognitive decline.
There are three main types of these fatty acids: alpha-linolenic acid, or ALA; docosahexaenoic acid or DHA; and eicosapentaenoic acid, or EPA.
The human body can convert small amounts of ALA into EPA and DHA, but the main way people increase levels is by consuming foods and supplements that contain omega-3 fatty acids.
Clinical studies evaluated
As the BfR now writes, taking preparations containing omega-3 fatty acids in people with existing or impending heart disease can increase the risk of atrial fibrillation, a disorder of the heart rhythm.
This was the result of an evaluation of several clinical studies by the European Medicines Agency (EMA). In these studies, patients either took medicines or nutritional supplements containing omega-3 fatty acids.
The clinical studies primarily examined people who already had a cardiovascular disease (i.e. a disease affecting the heart or blood vessels) or were at increased risk of it.
Similar high dosages to medicines
The EMA’s evaluation found that the risk of atrial fibrillation depended on the dose of omega-3 fatty acids consumed and was greatest at the highest tested dose of 4 grams per day.
Dietary supplements with omega-3 fatty acids are offered, for example, in the form of fish oil capsules and sometimes contain doses similar to those of pharmaceuticals.
Unlike medications, nutritional supplements are freely available in stores and can be taken over long periods of time without medical supervision. This makes it easier to overlook possible undesirable health effects.
Only take after medical advice
The BfR therefore recommends that consumers with heart disease or corresponding risk factors in particular only take preparations containing omega-3 fatty acids, such as dietary supplements, in consultation with a doctor, especially over a longer period of time.
It is important to know that omega-3 fatty acids are also found in fish. Regular consumption of fish (once or twice a week) has health-promoting effects, for example on fat metabolism. This means that intake levels of omega-3 fatty acids, which are associated with the health risks described, are not achieved.
Dietary supplements are not intended to cure or relieve any disease. Such preparations are not medicines, but foods that can supplement the normal diet. They must be safe and they must not have any adverse health effects.
Long-chain omega-3 fatty acids from fish oil such as DHA and EPA are said to have health-promoting properties: They are said to prevent cardiovascular and vascular diseases, among other things.
Therefore, fish oil is not only offered in dietary supplements, but also used to fortify foods.
In this context, the BfR assessed the health risk of an increased intake of the omega-3 fatty acids DHA and EPA in 2009 and pointed out that high intake levels show evidence of increased cholesterol levels, an impairment of the immune system in older people There was mortality in people with heart disease and an increased tendency to bleed.
And the long-term effects of increased intake have not been sufficiently investigated. The BfR therefore recommended setting maximum levels for the addition of DHA and EPA to food products. This recommendation is still valid.
The BfR does not consider it necessary for healthy people to take fish oil concentrates via dietary supplements, especially if they regularly consume fish. (ad)