Healthy habits can prevent disease

Five new studies provide evidence to support simple steps we can take to prevent illness and improve our overall health. In the June issue of The American Journal of Medicine, researchers report on fish consumption to reduce the risk of colon cancer; the effectiveness of hypnotherapy and acupuncture for smoking cessation; regular teeth cleaning to improve cardiovascular health; the effectiveness of primary care physicians in weight loss programs; and the use of low-dose aspirin to reduce cancer risk.

Colorectal cancer is the third leading cause of cancer death in the Western world. Research linking fish consumption and the risk of colorectal cancer has been inconclusive, although people who live in countries with high levels of fish consumption are known to develop the disease less frequently. Now, scientists from Xi'an, China, have reviewed the literature and find that eating fresh fish regularly reduces the risk of colorectal cancer by 12%. They evaluated 41 studies on fish consumption and colorectal cancer risk published between 1990 and 2011 and tracked cancer diagnoses. The protective effect of fish consumption is more prominent in rectal cancer than in colon cancer. The risk reduction for rectal cancer was as much as 21%, whereas the reduction for colon cancer was 4%.

"Despite the fact that colon and rectal cancer share many features and are often referred to as 'colorectal cancer,' they tend to demonstrate many different characteristics," notes lead author Daiming Fan, of the Fourth Military Medical University. "One possible reason for the difference may be because colon cancers are generally more molecularly diverse, whereas rectal cancers mostly arise via a single neoplastic pathway."

Mark J. Eisenberg, MD, MPH, of McGill University, in Montreal, Quebec, and colleagues report that the use of unconventional smoking cessation aids, including acupuncture and hypnotherapy, results in substantial increases of smoking cessation. A meta-analysis of 14 trials found that smokers who underwent hypnotherapy were 4.55 times more likely, and those who underwent acupuncture were 3.53 times more likely, to abstain from smoking than those who did not. Aversive smoking may also help smokers quit; however, there were no recent trials investigating this intervention.

Regular tooth scaling is associated with a decreased risk for future cardiovascular events. A study by H-B. Leu, MD, of Taipei Veterans General Hospital, Taiwan, and colleagues examined 10,887 subjects who had undergone tooth scaling, and 10,989 subjects who had not received tooth scaling. During an average follow-up period of seven years, the group that had undergone tooth scaling had a lower incidence of myocardial infarction, stroke, and total cardiovascular events. Increasing frequency of tooth scaling correlates with a higher risk reduction.

A study by William C. Haas, MD, of East Carolina University, Greenville, NC, and colleagues finds that physicians in primary care practices can be as effective as weight loss clinics in helping the moderately obese lose weight. Patients received behavioral modification sessions and a diet plan partially or fully supplemented by meal replacements at either a primary care clinic or a weight loss center. Primary care clinics were as effective as weight loss centers at reducing weight, and better at reducing body fat. Regardless of location, participants completing 12 weeks of treatment lost an average of 11.1% of their body weight. Participants who selected full meal replacement had better results.

Low-dose aspirin, a common strategy for preventing cardiovascular disease, can also reduce nonvascular deaths, including cancer deaths. A meta-analysis of 23 randomized studies by Edward J. Mills, PhD, MSc, of the University of Ottawa, Ontario, Canada, and colleagues offers conclusive evidence that low-dose aspirin offers cancer preventive effects, and showed significant treatment effects after approximately four years of follow up.