Nearly all the studies that have found garlic effective at reducing cholesterol use powered garlic alliin content. However,several studies use garlic that is simply aged, without any attempt to keep alliin intact. Because its processing is simpler, aged garlic is relatively inexpensive.
In one study ,41 men with moderately high cholesterol took either placebo or 7.2 g of aged garlic extract daily for 4 to 6 months. Aged garlic reduced total cholesterol by 6.1% more than placebo,and reduced LDL by 4.6% more than placebo.
While positive, these results were less impressive than what has been seen in studies of garlic powder standardized to 1.3% alliin.However, since there have not been any head-to -head comparisons,we can’t really say for sure that aged garlic is less effective than standardized powdered garlic.
Nonetheless,many experts suspect that it is weaker because it contains fewer of the probable active ingredients.