title: Lack of effect of fish oil supplementation on blood pressure in treated hypertensives.
abstract: Fish and fish oils have been reported to reduce blood pressure in normotensives and untreated hypertensives. The present study examined the effect of dietary supplementation with fish oil on blood pressure in 20 treated hypertensives with controlled blood pressures who continued their usual antihypertensive drug treatment throughout. A double-blind, randomized crossover design was used, with two phases, each of 8 weeks' duration. In one phase, subjects took fifteen 1 g fish oil capsules (Lipitac; Reckitt and Colman Pharmaceuticals, Sydney, Australia) daily, and in the other, 15 capsules of identical appearance containing 1 g olive oil daily. There was no difference between the treatment phases for any blood pressure parameter, heart rate or body weight, but blood pressure was lower in both phases compared with pretreatment values. The fasting plasma triglyceride concentration was 30% lower in the fish oil phase (P less than 0.001), but there was no difference between the phases for plasma concentrations of total or high-density lipoprotein (HDL) cholesterol. We conclude that, in treated hypertensives with controlled blood pressures, any additional fall in blood pressure produced by dietary supplementation with fish oil is so small that the requirement for antihypertensive drug therapy is unlikely to be reduced.
authors.affiliation: Hypertension Clinic, Flinders Medical Centre, Bedford Park, Australia.
authors.forename: L M
authors.initials: LM
authors.lastname: Wing
authors.forename: P J
authors.initials: PJ
authors.lastname: Nestel
authors.forename: J P
authors.initials: JP
authors.lastname: Chalmers
authors.forename: I
authors.initials: I
authors.lastname: Rouse
authors.forename: M J
authors.initials: MJ
authors.lastname: West
authors.forename: A J
authors.initials: AJ
authors.lastname: Bune
authors.forename: A L
authors.initials: AL
authors.lastname: Tonkin
authors.forename: A E
authors.initials: AE
authors.lastname: Russell
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000187:drug effects*; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D005395:Fish Oils / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000178:diet therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010938:Plant Oils / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D014280:Triglycerides / Q000097:blood
chemical_list: D008076:Cholesterol, HDL; D005395:Fish Oils; D010938:Plant Oils; D014280:Triglycerides; D002784:Cholesterol