Study suggests natural supplement usually taken for joint pain may also stem lung cancer
Glucosamine is an amino sugar produced naturally in the body. Because it plays a key role in building cartilage (the connective tissue that cushions the joints) many older people take glucosamine supplements to reduce inflammation from osteoarthritis, a type of arthritis that occurs when cartilage breaks down or is lost.
Recently, a team of researchers from the Fred Hutchison Cancer Research Center and the Portland VA Medical Center have found that taking glucosamine may have a surprising additional benefit: participants in a study who used the supplement for a long period of time developed fewer cases of adenocarcinoma (a type of cancer) of the lung than others their age who did not take the supplement.
The team's study, titled "Use of Glucosamine and Chondroitin and Lung Cancer Risk in the VITamins and Lifestyle (VITAL) Cohort," was published in the journal Cancer Causes and Control in September 2011.i The beneficial effect of glucosamine was seen in people who used it for three years or more, and appeared to be similar to that of anti-inflammatory medications such as aspirin and ibuprofen.
Since inflammation is known to play an important role in the development of lung and other cancers, anti-inflammatory medications have long been considered to have a possible protective role. However, in contrast to aspirin and ibuprofen, glucosamine has no known adverse effects.
In their study, the team analyzed data on nearly 77,000 men and women aged 50 to 76 living in Washington State. Each had agreed to participate in the VITamins And Lifestyle (VITAL) Study, a cohort study of the associations of vitamin and mineral supplement use with cancer risk. (Vitamin and mineral supplements are among the most commonly used drugs in the United States, despite limited evidence on their benefits or risks.)
Participants entered the study from 2000 through 2002 by completing a detailed questionnaire on their use of supplements, their diet and other cancer risk factors.
Using data collected from these participants, the research team found that those taking glucosamine at least four times a week for at least three years had about half the rate of lung adenocarcinomas as those who did not take the supplement—meaning that their risk of developing this common type lung cancer was cut approximately in half. This reduction was not modified by whether patients smoked or not, or whether they took non-steroidal anti-inflammatory drugs, or NSAIDs.
They also looked at another supplement used in treating arthritis, called Chondroitin, and found that there was no relationship between taking that drug and the risk of developing lung cancer.
Theodore Brasky, PhD, post-doctoral research fellow at the Fred Hutchison Cancer Research Center and the study's principal author, tempered the study's conclusions by saying, "Our study is the first to examine the association between the use of glucosamine and similar supplements and cancer risk. More research is needed to determine whether these findings are real, rather than the result of chance."
Study co-author Christopher Slatore, MD, a physician at the Portland VA Medical Center, added, "If our findings are validated, they would be of great interest to cancer scientists, as there is a need to find medications that can be safely taken long-term in the hopes of preventing cancer."
The study was funded by the National Institutes of Health. Dr. Slatore is supported by a VA HSR&D Career Development Award and by resources from the Portland VA Medical Center.
Lung cancer is the leading cause of cancer deaths in the United States. According to the Centers for Disease Control, in 2007 203,536 Americans were diagnosed with lung cancer and 158,683 people died from it.ii
i. Brasky TM, Lampe JW, Slatore CG, White E. Use of glucosamine and chondroitin and lung cancer risk in the VITamins And Lifestyle (VITAL) cohort. Cancer Causes Control. 2011;22:1333-1342.
ii. United States Cancer Statistics, developed by the National Program of Cancer Registries, Centers for Disease Control and Prevention, U.S. Department of Health and Human Services, http://apps.nccd.cdc.gov/uscs/