Anticancer Properties of Garlic
Antioxidants in Garlic and their Effects on Human Cancers
Garlic (Allium sativum) can be classified as a dietary anticarcinogen, whose antioxidant properties can reduce the incidence of certain human cancers
Fruit and Vegetables
In 1997 an article entitled ‘Cancer undefeated’ appeared in the New England Journal of Medicine (336: 1569–1574) whose bleak assessment was that overall death rates from cancer had shown little change since the early 1970s. There was clearly a need for an increased emphasis on cancer prevention, and for more than twenty years, a theme has emerged, flagging up smoking, alcohol and poor diet as some of the major risk factors for development of the disease. As far as diet is concerned, the value of fruit and vegetable consumption was promoted, with researchers claiming that plant-based diets prevented 20%–50% of all cases of cancer. For example, in 1982 the National Research Council in the United States published ‘Diet, nutrition & cancer’ through National Academy Press.
Lower Mortality
The positive effects of consuming fruit and vegetables have been attributed to the antioxidant properties of certain substances contained in them. For instance, in 1992 Ziegler et al wrote an article in Cancer Research (52: Supplement; 2060S–2066S) entitled ‘Does β-Carotene explain why reduced cancer risk is associated with vegetable and fruit intake?’
Garlic (Allium sativum)
This is an allium vegetable with a history of culinary and medicinal use extending back over 4,000 years. In a 2005 article for Critical Reviews in Food Science and Nutrition (45: 607–621), Bhagyalakshmi et al point out that Louis Pasteur noted the anti-bacterial properties of garlic in the 1800s; during World Wars One and Two the Soviet placed a heavy reliance on garlic as an antiseptic to disinfect open wounds (it became known in the World War Two as ‘Russian penicillin’); and in the 1950s Dr Albert Schweitzer used garlic to treat cholera, typhus and amoebic dysentery. If a garlic clove is crushed over one hundred sulphur-containing compounds are released. However, allicin is the most important of the biologically active compounds produced by crushed garlic, formed by the action of an enzyme, allinase on alliin.
Garlic’s Anticarcinogenic Properties
An early study of the preventive effects of garlic on human cancer was reported in 1988 by Blot et al in Cancer Research (48: 3518–3523), and entitled ‘Diet and high risk of stomach cancer in Shandong, China.’ The study found that in Gangshan county, where residents consume a relatively high amount of garlic, the death rate from gastric cancer was 3.45 per 100,000. However, in Quixia county, where garlic intake was low, the death rate from gastric cancer was 40 per 100,000. In 1989 the results of an Italian study entitled ‘A case control study of gastric cancer and diet in Italy’, were reported in the International Journal of Cancer (44: 611–616) by Buiotti et al. They had found an inverse relationship between garlic consumption and gastric cancer in certain areas of the country.
