Plant-Based Therapeutics, Volume 3

The World Health Organization, the National Cancer Institute, and the American Institute for Cancer Research have stated that including garlic in a regular diet is associated with a lower risk of cancer. Additionally, the U.S. Pharmacopoeia and other organizations have published a monograph outlining the process for Aged Garlic Extract (AGE).
AGE is produced through extended extraction with 15-20% ethanol at room temperature. During this process, compounds that contribute to the characteristic flavor are converted into stable substances. AGE contains water-soluble sulfur compounds and oil-soluble allyl sulfides. The compounds formed during aging provide numerous medicinal benefits.
Black garlic (BG) is produced by applying moderate heat and humidity for six to eight weeks. During this process, the pungent compounds in raw garlic are transformed into stable compounds. BG has a sweet flavor and a jelly-like texture. The warm temperature triggers the Maillard reaction, giving it a dark brown color and producing health-promoting compounds not found in raw garlic.
In 1858, Louis Pasteur described the antibacterial effect of garlic, highlighting its broad antibiotic spectrum against both gram-positive and gram-negative bacteria. Notably, raw garlic juice is effective against many common pathogenic intestinal bacteria that cause diarrhea; garlic also works against strains resistant to antibiotics. The combination of garlic with antibiotics shows partial or full synergism, and a complete absence of resistance has been observed repeatedly. Additionally, garlic inhibits toxin production by microorganisms. 
In 1990, the US National Cancer Institute launched the Designer Food Program to identify foods that play important roles in cancer prevention. The program concluded that garlic might be the most powerful cancer-preventive food. Epidemiological studies and laboratory research have demonstrated the protective effects of garlic and explained the mechanisms behind its cancer chemopreventive properties. These include the regulation of metabolizing enzymes that activate and detoxify carcinogens, the prevention of DNA adduct formation, antioxidant and free radical scavenging properties, and the control of cell growth, programmed cell death, and immune responses. Garlic-derived products also influence cell-signaling pathways that regulate abnormal cell growth, providing strong chemopreventive and therapeutic benefits.