Fish oil supplementation does not lower plasma cholesterol in men with hypercholesterolemia. Results of a randomized, placebo-controlled crossover study.
OBJECTIVE
To determine the effects of fish oil supplementation on plasma cholesterol in middle-aged men with isolated hypercholesterolemia.


METHODS
Randomized double-blind placebo-controlled (safflower oil) two-period crossover trial with 12-week treatment periods.


METHODS
Outpatient general medicine clinic at a university-affiliated Veterans Affairs hospital.


METHODS
Thirty-eight men with plasma cholesterol between 5.68 and 7.76 mmol/L (220 to 300 mg/dL), triglyceride levels less than 3.39 mmol/L (300 mg/dL), and free of coexisting diseases.


METHODS
Fish oil and placebo (safflower oil) supplementation. After basal measurements and a 4-week lead-in period, twenty 1-g capsules of either fish oil or placebo oil were provided for 12 weeks (period 1). After a 4-week washout phase participants then received the other oil for an additional 12 weeks (period 2).


RESULTS
Blood was drawn at the beginning and end of each study period and analyzed for levels of total cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides, apolipoprotein A1, and apolipoprotein B. Low-density lipoprotein (LDL) cholesterol was calculated using the Friedewald equation. Total and LDL cholesterol increased from the before treatment values by 4.8% and 9.1%, respectively, after ingestion of fish oil. Compared with placebo, LDL cholesterol was significantly higher (4.5 compared with 4.1 mmol/L, P = 0.01) and triglycerides lower (1.3 compared with 1.8 mmol/L, P = 0.01) after fish oil. Total and HDL cholesterol and apolipoprotein A1 and B levels did not differ.


CONCLUSIONS
Fish oil supplements do not lower plasma cholesterol levels in middle-aged men with hypercholesterolemia without elevated triglycerides. They should not be recommended as a method to lower plasma cholesterol in these patients.
Wilt
T J
TJ
Minneapolis Veterans Affairs Medical Center, Minneapolis.
Lofgren
R P
RP
Nichol
K L
KL
Schorer
A E
AE
Crespin
L
L
Downes
D
D
Eckfeldt
J
J
D000328:Adult; D001053:Apolipoproteins / Q000097:blood; D002784:Cholesterol / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004311:Double-Blind Method; D015525:Fatty Acids, Omega-3 / Q000097:blood; D005395:Fish Oils / Q000627:therapeutic use*; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D010743:Phospholipids / Q000097:blood; D016032:Randomized Controlled Trials as Topic; D012450:Safflower Oil; D014280:Triglycerides / Q000097:blood
D001053:Apolipoproteins; D008078:Cholesterol, LDL; D015525:Fatty Acids, Omega-3; D005395:Fish Oils; D010743:Phospholipids; D014280:Triglycerides; D012450:Safflower Oil; D002784:Cholesterol