Watercress extract could protect smokers against cancer

Watercress extract has been shown to detoxify certain carcinogens in smokers, which researchers say could be a tool in fighting cancer.

“Cigarette smokers are at far greater risk than the general public for developing lung cancer, and helping smokers quit should be our top cancer prevention priority in these people,” says Dr. Jian-Min Yuan, associate director of the University of Pittsburgh Cancer Institute’s (UPCI) Division of Cancer Control and Population Science.

He notes, however, that “nicotine is very addictive, and quitting can take time and multiple relapses.”

Dr. Yuan and colleagues presented their phase 2 clinical trial yesterday at the American Association for Cancer Research Annual Meeting in New Orleans, LA.

According to the Centers for Disease Control and Prevention (CDC), cigarette smoking is responsible for more than 480,000 deaths each year in the US. It does damage to almost every organ in the body and causes many diseases.

As of 2014, 16.8% of all adults in the US – which is 40 million people – were current cigarette smokers.

“Having a tolerable, nontoxic treatment, like watercress extract, that can protect smokers against cancer would be an incredibly valuable tool in our cancer-fighting arsenal,” says Dr. Yuan.

Effect stronger in smokers who lack toxin-processing genes

To further investigate, Dr. Yuan and colleagues enrolled 82 cigarette smokers in a randomized clinical trial. During the trial, the participants took either 10 mg of watercress extract that was mixed in 1 ml of olive oil four times per day for a week, or they took a placebo.

All participants continued their regular smoking habits during the trial period.

After a so-called wash-out period, during which they did not take anything for a week, the participant groups switched; those who received the placebo now received the extract and vice versa.

Results showed that in just 1 week, the smokers who took the watercress extract had a 7.7% reduction in activation of nicotine-derived nitrosamine ketone, which is a substance found in cigarette smoke.

Additionally, the watercress extract increased benzene detoxification by 24.6% and acrolein by 15.1%. These toxins are also found in cigarette smoke.

Interestingly, there are two specific genes that are involved in a genetic pathway that helps the antioxidant glutathione remove carcinogens from the body. Participants who lacked these two genes had a greater benefit in taking watercress extract, the researchers say.

In detail, their detoxification of benzene increased by 95.4%, their acrolein by 32.7% and their crotonaldehyde by 29.8% when they took the watercress extract.

Although these results are very promising, the researchers say they must first carryout a phase 3 clinical trial in hundreds of people before this treatment can be recommended for smokers.

Furthermore, Dr. Yuan cautions that, although eating watercress is good for health, it is not likely to have the same benefits as the extract form.

Medical News Today recently reported that even light hookah use can cause lung abnormalities.