fitness related header

Health Benefits of Garlic

garlic cloves

Photo by the Corel Corporation

The commonly used plant and food flavoring, garlic (Allium savitum), is known to have numerous health benefits. Research studies have shown garlic to possess antioxidant, anti-inflammatory, anticarcinogenic, antiviral, and antifungal properties. The substance allicin is the best known active ingredient in garlic, but garlic contains many active compounds in addition to this.

Research studies have shown that garlic, including garlic extract, also has many cardiovascular benefits, such as helping to lower blood pressure and preventing platelet aggregation. It has also been shown to lower serum lipid and cholesterol levels, so consumption of garlic or garlic extract may prevent the development of atherosclerosis.

Anticarcinogenic Properties of Garlic

Garlic has antiaging properties and is able to neutralize free radicals in the body and brain. Free radicals are molecules or atoms that contain an unpaired electron. Because it has an unpaired electron it can easily combine with another molecule creating a chemical reaction. Excess free radicals are often formed during biochemical processes that occur during the metabolism of food, especially fats. Excess free radicals can damage tissue and even DNA, which may lead to cancer. One way that garlic may help to prevent cancer is by neutralizing excess free radicals.

Garlic has been shown to inhibit skin cancer in mice and to reduce skin tumor size in humans (Tilli et al., 2003). In this study the garlic compound (ajoene) was applied topically to the cancer (it was not consumed) and it reduced the tumor size in 17 out of 21 of the patients (Tilli et al., 2003).

Garlic consumption has also been shown to prevent breast cancer. One study by Chu et al. (2006) reported that garlic consumption may decrease the ability of cancer to metastatisize (spread to other regions of the body). In their study they reported that it was two water soluble compounds found in garlic (S-allylcysteine and S-allylmercaptocysteine) that prevented the cancer from spreading.

In addition, research has shown that a compound in garlic inhibits the growth of prostate cancer (Chu et al., 2007; Howard et al., 2007).

Garlic and Testosterone

Does garlic consumption increase testosterone? One study found that rats fed high protein (casein) diets that were also fed garlic powder had increased testosterone levels at the end of the 28 day study (Oi et al., 2001). In contrast, rats in this study that were fed the high protein without the garlic did not show an increase in testosterone production.


As you can see, garlic provides many health benefits and the only drawback to garlic is that ingesting it often leads to bad breath. If the problem with garlic breath and odor bothers you, there are odorless garlic supplements available, such as Kyolic.


Chu, Q., Ling, M.T., Feng, H., Cheung, H.w., Tsao, S.W., Wang, X., and Wong. Y.C. (2006). A novel anticancer effect of garlic derivatives: Inhibition of cancer cell invasion through restoration of E-cadherin expression. Carcinogenesis 27:2180-2189.

Chu Q., Lee D.T., Tsao S.W., Wang X., and Wong Y.C.(2007). S-allylcysteine, a water-soluble garlic derivative, suppresses the growth of a human androgen-independent prostate cancer xenograft, CWR22R, under in vivo conditions. BJU international 99:925-932.

Howard E.W., Ling M.T., Chua C.W., Cheung H.W., Wang X., and Wong Y.C.(2007). Garlic-derived S-allylmercaptocysteine is a novel in vivo antimetastatic agent for androgen-independent prostate cancer. Clinical Cancer Research 13:1847-1856.

Oi Y., Imafuku M., Shishido C., Kominato Y., Nishimura S., and Iwai K. (2001). Garlic supplementation increases testicular testosterone and decreases plasma corticosterone in rats fed a high protein diet. Journal of Nutrition 131: 2150-2156.

Tilli C.M., Stavast-Kooy A.J., Vuerstaek J.D., Thissen M.R., Krekels G.A., Ramaekers F.C., and Neumann H.A. (2003). The garlic-derived organosulfur component ajoene decreases basal cell carcinoma tumor size by inducing apoptosis. Archives of Dermatological Research 295: 117-123.