A recent study, published in the November issue of the American Journal of Preventive Medicine, showed a significant deficiency in the public's understanding of food labels. In the study, poor label comprehension was correlated with low-level literacy and numeracy skills, but even patients with higher literacy could have difficulties interpreting labels.
Not only could these findings point to a need for simpler labels, but they could also add weight to arguments coming from the supplement industry claiming wordy FDA-approved health claims on packaging are too confusing for consumers.
Researchers from Vanderbilt University Medical Center questioned 200 patients from a wide socioeconomic range. One part of the survey asked participants to interpret food labels for nutrient content by the amount of food consumed. The other part asked patients to choose which foods had more or less of a certain nutrient.
Only 37 percent of patients could calculate the number of carbohydrates consumed from a 20-ounce bottle of soda that contained 2.5 servings. While only 60 percent could calculate carbohydrates consumed if they ate half a bagel, when the serving size was a whole bagel.
"There are many opportunities for health care providers to improve how they talk to patients about using food labels and following diets," said lead author Russell Rothman. "There are also opportunities for the FDA to improve how food labels are designed in order to improve how patients take care of their nutrition."
In the supplement and functional foods industries, FDA-approved health claims are highly sought after by ingredients manufacturers because they can enhance the credibility of a healthy product. However, critics have said these health claims are often worded so tenuously that their intended benefit is lost in the reading.
Companies such as American Longevity have been involved in campaigns to relax rules on health claims, as they hold that restricting companies' communication of the benefits of certain ingredients infringes the right to free speech.
For example, the qualified health claim on pancreatic cancer reads: "Very limited and preliminary scientific research suggests that eating one-half to one cup of tomatoes and/or tomato sauce a week may reduce the risk of prostate cancer. FDA concludes that there is little scientific evidence supporting the claim."
With nutrition labels, the fear is that the public will overeat or not get enough of certain nutrients even if they have the best diet intentions.
"Poor understanding of nutrition labels can make it difficult for patients to follow a good diet," said Rothman. "Of particular concern are situations that involve interpretation and application of serving size."
Half of the survey questions involved products labeled as "reduced carb", "low carb", or designed for "a low-carb diet".
The demographics of the participants reflect a possible deficiency in the education system coupled with a critical health need for these patients to successfully decipher labeling.
Sixty-eight percent of patients had at least some college education. Seventy-seven percent had at least ninth grade level literacy skills, but 63 percent of patients had less than 9th-grade numeracy skills.
Over 40 percent of the participants had a chronic illness - such as hypertension or diabetes - requiring specific dietary intervention and 23 percent reported being on a specific diet plan.
Most patients reported using food labels and most claimed they are easy to understand.