Got calcium?  UWM researcher finds that food labels confuse consumers

Consumers often don't get nutritional information they need

Current food labeling leads to under-consumption of calcium, according
to this study. Those who were taught how to translate the information
consumed more. Researchers believe the same is true for other beneficial

A woman at risk for osteoporosis is told by her doctor to get
1,200-1,500 milligrams of calcium every day. But when she looks at the
Nutrition Facts panel on a carton of yogurt or a jug of milk, she finds
that calcium is only listed by “Percent Daily Value” (%DV).

How does she convert that to milligrams?

If she’s like most of us…she can’t. And neither can her doctor.

Those were among the findings of research conducted by Laura A.
Peracchio, professor of marketing at the University of
Wisconsin-Milwaukee (UWM), and Lauren Block, professor of marketing at
Baruch College (CUNY). The results were so compelling that the U.S. Food
and Drug Administration added information to its Web site on how to
translate %DV to milligrams.

The problem

The research, which involved three separate studies and a follow-up, is
discussed in “The Calcium Quandary: How Consumers Use Nutrition Labels
for Daily Diet,” published in the Journal of Public Policy and
Marketing. Peracchio and Block found that:

* In Study 1, only two of 37 respondents correctly translated the
calcium information on a carton of yogurt from %DV to milligrams.

* In Study 2, when 20 physicians were shown the same label, only
six gave the right answer in milligrams. (Asked how the calculation was
done, one physician who gave an incorrect answer replied: “I have no
idea. I made it up.”) Yet most doctors dispense calcium recommendations
to their patients in milligrams.

The central question of the research, Peracchio and Block write, is:
“How do consumers make food consumption decisions when product
information falls short of providing the nutritional knowledge needed
for personal health consumption goals?”

And the answer

The answer is found in Study 3, which involved 41 women who were
pregnant or breast-feeding. All had been told by their doctors or had
read independently that they needed 1,200-1,500 milligrams of calcium a

Half of the women were given a one-page calcium fact sheet including the
formula for converting % DV to milligrams. The formula is simple – % DV is
based on the average recommended calcium intake of 1,000 milligrams
daily. To convert % DV to milligrams, just add “0” to the percentage on
the label. For example, a carton of milk delivering 30% DV contains 300
milligrams of calcium.

The women who were given the fact sheet consumed significantly more
average daily calcium (a mean of 1,429.78 milligrams) than women who
were not given the fact sheet (a mean of 988.24 milligrams).

Current labeling leads to under-consumption of calcium, the research
showed. The women who were not given the fact sheet may have consumed
close to 100% DV of calcium daily, but it fell short of the 120-150% DV
they really needed.

“This is particularly worrisome with at-risk populations such as those
over 55 years of age, or pregnant or lactating women,” says Peracchio.

Teenage girls also need extra calcium, she points out, and a study
reported this summer in The New York Times suggests that consuming high
levels of vitamin D and calcium may offer some protection against the
most aggressive kinds of breast cancer.

Other nutrients affected

Peracchio and Block point out that the difficulty in translating the
Nutrition Facts panel on food products goes beyond calcium.

“The challenge of using the Nutrition Facts panel to make adequate food
consumption decisions is similar for other nutrients that consumers
often do not consume enough of, such as dietary fiber, vitamin A,
vitamin C, and iron….”

The Nutrition Facts panel is separated into two categories: the top of
the panel lists nutrients that should be limited (fat, cholesterol,
sodium, etc.); “good” nutrients are listed at the bottom (calcium,
fiber, iron, vitamins A and C, etc.).

“Much more attention and educational efforts have been paid to the
former than to the latter,” the research concluded.

“Helping people better navigate the consumer environment” is extremely
rewarding work, Peracchio says. She teaches courses in consumer
behavior, marketing strategy and nonprofit marketing at UWM’s Sheldon B.
Lubar School of Business, and also serves as an associate editor of the
Journal of Consumer Research, one of the top three journals in the
marketing field.