Garlic could protect from cancer and more may be better

Kathleen Blanchard's picture

Garlic consumed in large amounts could have anti-cancer properties. Researchers have developed a urine test that shows how eating more garlic correlates with less risk of cancer by protecting the body from the effects of toxins – new research shows that eating more garlic may be better.

A small study suggests that eating garlic helps the body fight cancer. Scientists have developed a urine test that measures how much garlic an individual consumes that also correlates with fewer compounds in the body that can cause cancer.

Earl Harrison, Dean’s Distinguished Professor of Human Nutrition at Ohio State, an investigator in Ohio State University’s Comprehensive Cancer Center, and senior author of the study explains, “Our results showed that those were inversely related to one another – meaning that the more we had the marker for garlic consumption, the less there was of the marker for the risk of cancer.”

The scientists say they wanted to develop tests that could measure cancer risk by testing the urine while also finding a way to find out how much garlic an individual consumes. The process relates to nitrogen containing compounds and the way the body converts some substances found in foods or contaminated water into substances that can cause cancer.


Consuming processed meats, certain high heat food preparation practices, and drinking contaminated water from agricultural runoff practices and industry exposes us to cancer causing agents called nitrates. A process known as nitrosation ensues that turns ingested compounds into cancer causing agents. Garlic could provide the body with a way to turn carcinogens into harmless chemicals, acting as a potent anti-cancer tool.

Measuring the presence of nitrosoproline in the urine indicates how much nitrosation occurs in the body. By testing urine for nitrosopolines in addition to a specific compound in the urine that indicates how much garlic a person has consumed told the scientists that eating more garlic could help the body fight cancer from ingestion of harmful substances that cause nitrosation.

Study participants who ate the most garlic – 5 grams daily – had the lowest levels of nitrosopolines in their urine, leading them to the conclusion that garlic could have anti-cancer properties, though they are not sure why.

The authors write, "What this research does suggest, however, is that garlic may play some role in inhibiting formation of these nitrogen-based toxic substances. This was very small pilot study, so it's also possible that the more garlic you have, the better it would be.”

The authors also say there is no harm in consuming garlic, so “go out and have as much as you want”. One glove of garlic that weighs between one and five grams could help prevent cancer. Ultimately, the researchers hope to find nutritional interventions that could stop the process that occurs in the body that leads to cancer.

Ohio State Research