Phactum sampling

Does Eating Candy Increase Your Longevity?

-- Meeting Report by Paula Crock

Well, probably not. That shouldn't be a surprise to most people, the ill effects of too much sugar in the diet are widely known. Even a study from Harvard University, as published in the Bucks County Courier Times and other places, that suggests that eating candy can lengthen your life, is surely viewed skeptically by many readers. However, how is a person to judge the validity of medical news when previous knowledge and common sense are not applicable? Should men be concerned at the increasing number of testicular cancer cases reported? Should parents be concerned at the rise in childhood brain cancer rates?

That was the issue addressed at September's presentation given by Epidemiologist Jeff Lewis and Toxicologist David Craigan. Jeff and David began their discussion with the Harvard study linking eating candy to longevity. Using the article that appeared in the Bucks County Courier Times the two demonstrated the use of Hill's Criteria of Causality, a method of determining the validity of medical news. Hill's Criteria consist of a series of questions to be asked about the study in question. It efficiently pointed out the weaknesses in the longevity claim. One example shown by Hill's Criteria was the lack of correlation between the amount of candy a person consumed and his increase in life-span.

From the Harvard study Jeff and David moved on to a more serious subject, cancer. They first discussed the difficulty in determining an actual change in cancer rates and then talked about a few specific cases. Cancer rate changes can be caused by other biologic factors, such as change in exposure or the reduction in death from other diseases, and by non-biologic factors, such as increased public awareness and changes in reporting methods. These other factors can cloud the issue of cancer rates and causes.

Stomach cancer, according to Jeff and David, is the best success story in the medical community's fight against cancer. In 1930 stomach cancer was the most common cancer in the US. Now, with improvements in agriculture and food preservation methods, stomach cancer is the 12th most common cancer in the US. Hurrah for science!

Jeff and David then talked about an interesting rise in childhood brain cancer rates in the mid-1980s. Studies finally showed that the rise was in fact non-biological in origin, the cause being the big jump in the sale of MRI machines in 1984. This led to many more cases of brain cancer being diagnosed since more pediatricians had access to MRIs as a diagnostic tool.

Finally Jeff and David talked about the apparent rise in testicular cancer rates over the last 25 years. The ABC News report they referenced contained scary headlines like "Up nearly 60% in Canada" and "Culprit could be environmental pollution." Unfortunately the report was all sensationalism and did not address the real issues behind the rise. From other sources Jeff and David found meaningful information about the rise, including a 10 times higher rate in whites than in Chinese-Americans, and the low number of cases reported relative to other types of cancer. These facts, they suggested, are what should be reported, since sensationalist reporting can lead to confusion, misdirected health resources, and the nocebo effect. [A downturn resulting from an neutral cause, a back-formation from "placebo."]

One example they talked about was a woman who wouldn't take smoking cessation drugs because she feared she would suffer from the side effects. David likened this to standing in the middle of I-95 and being concerned that your shoelace is untied. Jeff and David concluded their talk by warning us that there are soon to be some major changes in the reporting methods used by the medical community. These changes will introduce even more non-biologic factors to muddle up medical news reporting.