What It Does:
Some studies suggest that garlic may cause a moderate, short-term reduction in total cholesterol of about 4% to 12%, including decreases in triglycerides and LDL (bad) cholesterol. Garlic alone is probably not sufficient to treat people with significantly elevated cholesterol levels and garlic does not improve HDL (good) cholesterol levels.
There are more than 200 chemicals in garlic and some may interfere with other medications.
Quality Concerns and What ConsumerLab.com Tested for:
Some non-aged garlic preparations may not generate the amount of allicin regarded by some as effective due to use of poor quality (low allicin yield) garlic and/or low recommended dosages.
 
CL purchased fourteen garlic products and tested them for garlic-related compounds to determine whether or not they met their claims and the minimum standards for garlic quality applied in this review
 
What CL Found:
Not all garlic products are created equal. Eight out of the 14 products did not meet standards!
Our recommendations?
 
AVOID!
In 30 years of medical practice, I have never seen Garlic products significantly reduce cholesterol levels. (I wonder how much Larry King got paid for his testimonials!)
Save your money.