Yogurt and Diet: Media Blog Post II

In class one of the most common pitfalls we seem to discuss is the lack of clear operational definitions and vague subject groups. This problem immediately struck me in reading an article published January 24 on the "Health on Today" blog from the Today Show. The article's title proclaims quite generally "Yogurt Lovers have better diets," (which had me questioning from the start) and its second paragraph is riddles with numerous vague statements that fueled my questions for the rest of the paper: 

• As a group, people who said they ate yogurt also reported consuming higher amounts of other good-for-you foods, such as fruits, vegetables, nuts, fish and whole grains, than did people who didn't eat yogurt. And their diets obtained fewer calories from processed meats, refined grains and beer than did the diets of non-yogurt eaters, according to the study, which received some funding from a yogurt manufacturer

My first problem is with the unspecified subject group: who exactly is this group of "people" who claim to have a better diet because they also eat yogurt? Later on the article states that these "people" consisted of "slightly more than 6,500 adults, ages 19 to 89" who were all either children or grandchildren of participants in the Framingham Heart Study (this study began in 1948 following its subjects for almost 50 years to attempt to identify a common cause of heart attack or stroke for a group of people that did not have these problems to begin with). Although this data does help clarify something about the demographics of the subject group statements such as "slightly more" are also extremely vague. Does "slightly more" than 6,500 mean an additional ten adults or an additional hundred adults? This difference could easily skew their data if they were attempting to quantify something, say the average weight of their yogurt eaters. 

 The second problem I found is in the end sentence that reveals that the study "received some funding from a yogurt manufacturer," which immediately introduces a bias into the research. If the study is being funded by a yogurt manufacturer then it is not at all surprising that the results showed that eating yogurt was healthy for people. While this is certainly not to say that the researchers themselves hold a personal a priori conviction towards the benefits, or lack thereof, of yogurt, it cannot be ignored that monetary compensation was part of the equation. 

The last problem I found was in the conclusions they drew from the seeming lack of a measurable quantity in their data. 

Their methodology: 

• People participating in the study were asked to recall how often they ate a one-cup serving of yogurt. Their response was based on a 9-point scale, which ranged from a low of "never or less than one serving a month" to a high of "more than six servings a day."

Their conclusion:

• In addition to having a better-quality diet, the men and women who regularly spooned in some yogurt had higher potassium intakes. They also were 48 percent less likely to have inadequate levels of calcium; 38 percent less likely to be deficient in magnesium; and 55 percent less apt to have shortfalls of vitamin B12, a nutrient lacking in some older people's diets.

First off, their data is qualitative. They are depending on individuals ability to recall what they eat and report it honestly, and from what it seems this was not done on a daily basis but from participants recollection of general yogurt eating patterns over time. Second, the conclusion attempts to show a direct correlation between a good diet and yogurt consumption, factors that do not directly have anything to do with each other. This excludes numerous outside contributing factors, for example what if an individual has a "perfect" diet but is lactose intolerant? What about the quantity of other foods being consumed, or their activity level? 

Ultimately, I would hazard that an individual who reads this article and decides to add yogurt to their diet would likely not suffer any great detrimental effects. I hate to generalize (as the article does enough of this already) but yogurt is generally regarded as a "good" food to eat, so it is not this part of the conclusion that poses the problem. The articles many problems lack in the lack of operational definitions, undefined subject group, and sweeping conclusion which attempts to correlation yogurt consumption with overall dietary quality. 

Yogurt Lovers Have Better Diet