Garlic reduces TC to a modest extent , an effect driven mostly by the modest reductions in TAG , without appreciable LDL lowering or HDL elevation .
Higher baseline line TC levels and the use of dietary modification may alter the effect of garlic on these parameters .
In order to determine the impact of  garlic on total cholesterol ( TC ) , TAG levels , as well as LDL and HDL  , and establish if any variables have an impact on the magnitude of this effect , a meta- analysis was conducted .
The effect of a garlic preparation on plasma lipid levels in moderately hypercholesterolemic adults.
Lipid management is well established as an effective preventive and management tool for cardiovascular disease ( CVD ) . Health cl aims regarding the cholesterol lowering benefits of garlic are widespread . However , the clinical trial data are inconsistent . The effect of two doses of a commercial garlic preparation on plasma lipids were evaluated , compared to a placebo , in moderately hypercholesterolemic adults ( baseline low density lipoprotein cholesterol (LDL-C)=157 . 4+/-18.7 , mean+/-S.D. ) . Fifty-one adults , aged 51.8+/-8.3 years participated in a double-blind , placebo-controlled , parallel treatment trial conducted in an outpatient research clinic . They were r and omized to a placebo or a garlic botanical blend providing 500 or 1000 mg dehydrated garlic powder/day ( three groups , 16 - 18 subjects per group ) . Plasma lipids were assessed every 2 weeks for 12 weeks . The study was design ed with sufficient power to detect a 10 % relative decline in LDL-C. The absolute mean changes in LDL-C over 12 weeks were 0.0+/-4.3 , + 1.4+/-4.8 , and -10.1+/-6.8 mg/dl for the placebo , half-dose and full-dose , respectively . In the full-dose group , the LDL-C decrease of 6.1 % was not significantly different from the other groups ( P=0.5 ) . No significant differences were observed for total- or high-density lipoprotein cholesterol ( HDL-C ) , or triacylglycerol levels . In conclusion , the garlic powder preparation used in this study among moderately hypercholesterolemic adults did not significantly effect plasma lipids levels . There was no indication of a grade d affect by garlic dose over the range of 0 , 500 and 1000 mg/day . A small ( < 10 % ) effect on LDL-C levels or a threshold effect requiring larger doses are not eliminated by this study
Garlic reduces TC to a modest extent , an effect driven mostly by the modest reductions in TAG , without appreciable LDL lowering or HDL elevation .
Higher baseline line TC levels and the use of dietary modification may alter the effect of garlic on these parameters .
In order to determine the impact of  garlic on total cholesterol ( TC ) , TAG levels , as well as LDL and HDL  , and establish if any variables have an impact on the magnitude of this effect , a meta- analysis was conducted .