Adding monounsaturated fatty acids to a dietary portfolio of cholesterol-lowering foods in hypercholesterolemia.
BACKGROUND
Higher intake of monounsaturated fat may raise high-density lipoprotein (HDL) cholesterol without raising low-density lipoprotein (LDL) cholesterol. We tested whether increasing the monounsaturated fat content of a diet proven effective for lowering LDL cholesterol (dietary portfolio) also modified other risk factors for cardiovascular disease, specifically by increasing HDL cholesterol, lowering serum triglyceride and further reducing the ratio of total to HDL cholesterol.


METHODS
Twenty-four patients with hyperlipidemia consumed a therapeutic diet very low in saturated fat for one month and were then randomly assigned to a dietary portfolio low or high in monounsaturated fatty acid for another month. We supplied participants' food for the two-month period. Calorie intake was based on Harris-Benedict estimates for energy requirements.


RESULTS
For patients who consumed the dietary portfolio high in monounsaturated fat, HDL cholesterol rose, whereas for those consuming the dietary portfolio low in monounsaturated fat, HDL cholesterol did not change. The 12.5% treatment difference was significant (0.12 mmol/L, 95% confidence interval [CI] 0.05 to 0.21, p = 0.003). The ratio of total to HDL cholesterol was reduced by 6.5% with the diet high in monounsaturated fat relative to the diet low in monounsaturated fat (-0.28, 95% CI -0.59 to -0.04, p = 0.025). Patients consuming the diet high in monounsaturated fat also had significantly higher concentrations of apolipoprotein AI, and their C-reactive protein was significantly lower. No treatment differences were seen for triglycerides, other lipids or body weight, and mean weight loss was similar for the diets high in monounsaturated fat (-0.8 kg) and low in monounsaturated fat (-1.2 kg).


CONCLUSIONS
Monounsaturated fat increased the effectiveness of a cholesterol-lowering dietary portfolio, despite statin-like reductions in LDL cholesterol. The potential benefits for cardiovascular risk were achieved through increases in HDL cholesterol, further reductions in the ratio of total to HDL cholesterol and reductions in C-reactive protein. (ClinicalTrials.gov trial register no. NCT00430430.).
Clinical Nutrition and Risk Factor Modification Centre, St. Michael’s Hospital, Toronto, Ont., Canada. cyril.kendall@utoronto.ca
David J A
DJ
Jenkins
Laura
L
Chiavaroli
Julia M W
JM
Wong
Cyril
C
Kendall
Gary F
GF
Lewis
Edward
E
Vidgen
Philip W
PW
Connelly
Lawrence A
LA
Leiter
Robert G
RG
Josse
Benoît
B
Lamarche
D000328:Adult; D000368:Aged; D002318:Cardiovascular Diseases / Q000517:prevention & control; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D005229:Fatty Acids, Monounsaturated / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D005502:Food; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000178:diet therapy*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood*
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D005229:Fatty Acids, Monounsaturated; D014280:Triglycerides