Inflammation occurs with many painful and fatal diseases. Fish oil, a source of omega-3 fatty acids, may help curb the inflammation associated with chronic and acute diseases.
A recent review of clinical trials focusing on the effects of omega-3 from fish oil has shown that incorporating these complex fatty acids into treatment plans can provide benefits.
The trials showed a health benefit for both healthy individuals and for people suffering from various conditions, including cardiovascular disease, pancreatitis, Alzheimer’s disease, renal failure and sepsis.
This review was authored by Oscar D. Rangel-Huerta, a researcher with the Department of Biochemistry and Molecular Biology Molecular, Institute of Nutrition and Food Technology and Jose Mataix Biomedical Research Centre at the University of Granada in Spain.
The review examined 26 clinical trial studies by Asian, European, Canadian, Australian and American researchers on the effects of two types of fish oil omega-3 fatty acids: docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Rangel-Huerta and his colleagues found that DHA and EPA have the ability to reduce markers for inflammation across a wide range of people.
Inflammation is a necessary process that the body goes through when presented with harmful stimuli. This stimulus causes the body to make chemicals called eicosanoids, which control the inflammatory process. Examples of these chemicals include prostaglandins, prostacyclins and thromboxanes.
Cells in the body incorporate omega fatty acids into their cell walls. When inflammation is triggered enzymes turn these fatty acids into eicosanoids. Different fatty acids produce eicosanoids and omega-3 fatty acids make a specific series of eicosanoids called series 3 eicosanoids, which cause significantly less inflammatory effects than the more common series 2 eicosanoids.
Rangel-Huerta found more trials regarding fish oil and cardiovascular disease to include in the review than any other disease. Though there was some debate on the ideal dosage, fish oil proved to have positive effects in six out of the eight clinical trials dealing with cardiovascular disease.
Sepsis, commonly known as a blood infection, is inflammation resulting from an systemic infection that is most often bacterial. Many of the most detrimental symptoms are cause by inflammation. The review authors included 3 studies showing that intravenous parenteral administration of EPA and DHA lessened the damage of the septic inflammatory response and strengthened the immune response to the infection.
Two studies in the review covered renal disease, and both found fish oil improved inflammation marker levels compared to placebo. Fish oils benefits renal disease patients by reducing certain cardiovascular disease risks.
Two studies on the effects of fish oil on Alzheimer’s patients found opposed results. The first study found that fish oil helped reduce inflammatory immune responses, and the second study found no effects. This was probably due the dosage, which was roughly three times less DHA and EPA than the first study.
Rangel-Huerta and his colleagues found ten trials that studied the inflammatory response effects of fish oil on healthy users. A majority of the studies on healthy subjects found that fish oil had no effect on inflammatory marker levels compared to placebo.
However, three of the ten studies on healthy subjects found reductions in the patient’s inflammatory biomarker compounds.
A stronger dose of the omega-3 was associated with better anti-inflammatory results, both for one test on healthy subjects and for the successful trial on Alzheimer’s. Both of these trials used higher dosages and had more success.
Only two of the studies in this review had more than 100 subjects, so these studies suffer in general from low participation. Understanding of proper dosage levels is also a problem with research into omega-3 fish oil that will have to be addressed with further research.
Because of the positive effects fish oil can provide for many disease conditions, Rangel-Huerta and his colleagues encourage both the use of this supplement and further research that focuses on the different effects of different doses.
The available evidence indicates that there are at least some benefits in healthy people supplementing with fish oil, though a person should always consult a doctor before taking a new supplement.
There were no mentions of any adverse events or side effects resulting from the fish oil. Even though it was fairly safe during the trials, users of fish oil should never exceed maximum dosage because fish oil can cause vitamin A toxicity.
This review of clinical trials was published in the June issue of BMJ. Funding was partially provided by the Instituto de Salud Carlos III, which is a part of the Spanish Ministerio de Ciencia e Innovación.
Coronary artery disease is the leading cause of death in the United States and in the rest of the world. Estimates point to almost one half of all middle aged men and one third of all middle aged women in the United States developing some form of CAD. The primary symptom of angina, commonly known as chest pain, occurs when the artery is almost completely blocked.
Plaques made up of cholesterol and fibrous tissue lodge in the walls of the arteries that supply blood to the heart. Slow growth of the plaques can cause chest pain as they restrict blood flow to the heart muscle, and complete closure or rupture of the plaque can cause a myocardial infarction, commonly known as a heart attack, with resulting disability or death. CAD is primarily a disease of diet and habits, with the greatest risk factors coming from smoking, high blood pressure, high cholesterol, and diabetes.