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 .
A double-blind crossover study in moderately hypercholesterolemic men that compared the effect of aged garlic extract and placebo administration on blood lipids.
A double-blind crossover study comparing the effect of aged garlic extract with a placebo on blood lipids was performed in a group of 41 moderately hypercholesterolemic men [ cholesterol concentrations 5.7 - 7.5 mmol/L ( 220 - 290 mg/dL ) ] . After a 4-wk baseline period , during which the subjects were advised to adhere to a National Cholesterol Education Program Step I diet , they were started on 7.2 g aged garlic extract per day or an equivalent amount of placebo as a dietary supplement for a period of 6 mo , then switched to the other supplement for an additional 4 mo . Blood lipids , blood counts , thyroid and liver function measures , body weight , and blood pressure were followed over the entire study period . The major findings were a maximal reduction in total serum cholesterol of 6.1 % or 7.0 % in comparison with the average concentration during the placebo administration or baseline evaluation period , respectively . Low-density-lipoprotein cholesterol was also decreased by aged garlic extract , 4 % when compared with average baseline values and 4.6 % in comparison with placebo period concentrations . In addition , there was a 5.5 % decrease in systolic blood pressure and a modest reduction of diastolic blood pressure in response to aged garlic extract . We conclude that dietary supplementation with aged garlic extract has beneficial effects on the lipid profile and blood pressure  of moderately hypercholesterolemic subjects
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 .