MONDAY, Could 3, 2021 (HealthDay Information) — Many individuals take fish oil to guard their coronary heart, however a brand new examine means that prescription variations might elevate the danger of a standard coronary heart rhythm dysfunction.
At problem are prescription-strength omega-Three fatty acids, that are naturally present in fish oil. The drugs are sometimes prescribed to folks with very excessive triglycerides, a kind of blood fats linked to elevated danger of coronary heart assault and stroke.
In accordance with the American Coronary heart Affiliation, prescription omega-3s can decrease triglycerides by 20% to 30% in most individuals.
However the drugs are additionally controversial, as a result of their final advantages for the guts are unclear.
Now the brand new examine — an evaluation of 5 previous medical trials — suggests warning is so as. Total, trial sufferers given omega-3s had been over one-third extra more likely to develop atrial fibrillation (a-fib) than these given a placebo. The fish oil doses taken ranged from 0.84 grams to four grams per day.
A-fib is a standard coronary heart rhythm dysfunction, or arrhythmia, by which the guts’s higher chambers start to quiver chaotically as an alternative of contracting successfully.
A-fib is just not instantly life-threatening, nevertheless it’s “not benign,” both, mentioned Dave Dixon, one of many researchers on the examine and an affiliate professor at Virginia Commonwealth College (VCU), in Richmond.
Over time, Dixon mentioned, a-fib can result in issues like coronary heart failure or stroke.
Precisely how prescription-strength omega-Three might contribute to a-fib is unclear, based on Dixon.
Nevertheless, the elevated danger was pretty constant throughout the trials — extra constant, in truth, than coronary heart advantages had been, mentioned co-researcher Salvatore Carbone, an assistant professor at VCU.
In all 5 trials, there have been extra a-fib circumstances amongst omega-Three sufferers than placebo sufferers, although the distinction in danger was not statistically vital in all research.
However when the researchers pooled the outcomes of all 5 trials, there was a transparent outcome: Omega-Three sufferers had been 37% extra more likely to develop a-fib than placebo sufferers had been.
In distinction, just one trial confirmed that an omega-Three product might reduce the dangers of different coronary heart circumstances.
In that trial, dubbed REDUCE-IT, sufferers utilizing a product known as Vascepa (icosapent ethyl) noticed their danger of “cardiovascular occasions” drop by 25%. That included coronary heart assault, stroke and dying from cardiovascular causes.
Even in that examine, although, a-fib danger rose amongst omega-Three customers, by 35%.
Why has just one trial discovered coronary heart advantages? Once more, it is not but clear, Dixon mentioned.
However, he added, Vascepa is totally different from the fish oil merchandise examined within the different trials. It accommodates just one omega-3, known as EPA, whereas the opposite merchandise comprise a mixture of EPA and DHA.
And within the REDUCE-IT trial, Dixon mentioned, larger ranges of EPA in sufferers’ blood correlated to decrease cardiovascular dangers.
That hints, he mentioned, that specializing in EPA may be “the best way to go sooner or later.” However the conflicting findings on the advantages of omega-3s — together with the potential danger of a-fib — spotlight the necessity for extra research, the researchers mentioned.
The evaluation was revealed April 29 within the European Coronary heart Journal — Cardiovascular Pharmacotherapy.
Findings on the guts advantages of fish oil have certainly been “inconsistent,” mentioned Linda Van Horn, a member of the guts affiliation’s diet committee and a professor at Northwestern College Feinberg Faculty of Drugs, in Chicago.
And that features low-dose, over-the-counter fish oil dietary supplements.
“There are restricted and inconsistent information relating to the profit or danger of taking fish oil dietary supplements,” Van Horn mentioned.
So the guts affiliation recommends consuming two servings of fish every week as an alternative. Van Horn mentioned that fatty fish, akin to salmon, trout, albacore tuna and herring, are the very best sources of omega-3s.
The trials within the present evaluation examined prescription-strength omega-3s. However Carbone mentioned he can be cautious about over-the-counter fish oil dietary supplements, too.
“We do not know if over-the-counter merchandise might have these identical results,” he mentioned.
Over-the-counter fish oil is taken into account a dietary complement, so it isn’t regulated by the U.S. Meals and Drug Administration as a drug can be, Dixon identified.
Each he and Carbone mentioned it is best to speak to a physician or pharmacist earlier than beginning any fish oil product — and that individuals on prescription omega-3s ought to converse with their physician earlier than stopping.
Harvard Medical Faculty has extra on fish oil and coronary heart well being.
SOURCES: Salvatore Carbone, PhD, assistant professor, kinesiology and well being sciences, Virginia Commonwealth College, Richmond, Va.; Dave L. Dixon, PharmD, affiliate professor, ambulatory care, and vice-chair, medical providers, division of pharmacotherapy and outcomes science, Virginia Commonwealth College, Richmond, Va.; Linda Van Horn, PhD, RD, professor and chief, diet division, division of preventive medication, Northwestern College Feinberg Faculty of Drugs, Chicago, and member, Vitamin Committee, American Coronary heart Affiliation, Dallas; European Coronary heart Journal—Cardiovascular Pharmacotherapy, April 29, 2021, on-line