Scientists from from the Friedman School of Nutrition Science and Policy at Tufts found that adolescents who read nutrition labels often did not translate the information into healthier diets and, sometimes, instead increased their intake of fat.
"Nearly 80 percent of the adolescents reported sometimes or always reading nutrition labels although it didn't translate into healthier diets," said lead researcher Terry Huang.
He noted that while boys reading nutrition labels was associated with a higher fat intake girls' fat intake did not differ after reading nutrition labels.
The study involved more than 300 boys and girls ages 10 to 19, who were mainly Caucasian and African-American. The researchers found that more than 56 percent read nutrition labels some of the time, 22 percent always read them and nearly 22 percent never read them.
The youngsters who always read the labels were, according to Huang and his colleagues, those who consumed the greatest number of calories from fat.
The researchers suggested that this could be because boys read the labels simply to assess total calories or proteins from a desire to "bulk up". Girls, on the other hand, they think might focus on total calories, rather than fat.
"Little has been done to evaluate the influence of the uniform nutrition labels since they were introduced in the US in 1994. Early nutrition education that takes into account gender-specific issues is clearly needed to help the public better understand and use nutrition labels," said the authors (Journal of Adolescent Health, 2004, 35:399 - 401).
Last week Reuters reported that nutrition labels on foods should note the percentage of daily recommended calories the product contains. The purpose being to "shock you and tell you (that) you have consumed 50 percent of your dailycalories," according to Dr Lester Crawford, acting FDA commissioner.
This statement was in addition to the letter sent by the FDA's Dr Laura Tarantino to food producers in March saying that the government body intended to re-evaluate the flexibility of the serving size regulations and warned it would take action against any company disobeying the rules.
"The FDA encourages the food industry to review its nutrition information and ensure that the serving size declared is appropriate for the commodity in question," said the letter.
Since then, several food companies have announced measures that will make the information on their products more in line with the government's suggestions.
Last month, for example, Kraft Foods announced new labels, to be used on a number of products that contain between two and four servings, that will include figures for calories, fat, cholesterol and sodium for the whole contents of the package as well as one serving, something which is missing on many package labels.
Coca-Cola and PepsiCo also recently announced that they had decided the time was right to comply with FDA recommendations. From the end of this year Coca-Cola North America and Pepsi-Cola will start rolling out 20 ounce bottles with more detailed nutritional labeling.
The modified packaging labels will provide expanded nutritional information - including calories, fat, sodium, carbohydrates, sugars and protein - to help consumers choose the beverages that are right for them, according to the company.
At present the bottles only show information for eight ounces and indicate the total number of servings per package. The FDA has recommended that all food and drink manufacturers revise their labeling for products that can be consumed at one time.