Ben Sheidler, a spokesman for Coca-Cola, said the company's course materials are based on independent, third-party research. He said Coca-Cola is acting responsibly by working to provide professionals with the facts surrounding its products.
Coca-Cola also said its surveys show the vast majority of participants in its classes find them helpful and "free of commercial bias."
But some say companies would never present information that doesn't serve their interests. Elizabeth Lee, a registered dietitian in Los Angeles and one of the founders of Dietitians for Professional Integrity, noted that the classes typically have a message that supports the company's products.
"It's getting harder and harder to really find something that isn't total baloney," said Debra Riedesel, another registered dietitian based in Des Moines, Iowa.
Part of what makes the issue so thorny is the deluge of research on nutrition, which is rarely definitive and often conflicting.
It's often said, for example, that snacking between meals can lead to weight gain. But a report earlier this year in the New England Journal of Medicine contended that no high-quality studies supported the claim. Underscoring how tangled matters can become, many of the report's authors had financial ties to food, beverage and weight-loss product makers.
"When it comes to research, the truth is somewhere in the middle," said Tina Miller, a registered dietitian in South Lyon, Mich.
INFLUENCE IN AND OUTSIDE THE CLASSROOM
For companies, the classes can be a chance to spotlight new products. At culinary demonstrations at the conference in Houston, for example, Kellogg and PepsiCo showcased recipes incorporating their products.
And the educational outreach to dietitians doesn't end in the classroom. Frito-Lay, which is owned by PepsiCo Inc., said more than a thousand dietitians are signed up to receive "SnackSense," a newsletter from its online resource for health professionals. A recent issue highlighted the moderate sodium levels of a new line of Tostitos and offered recipes using the chips.
Several times a year, the company also hosts tours of its plants for dietitians it identifies as being quoted in the media on healthy eating tips, according to a Frito-Lay spokesman.
PepsiCo also recently established the Quaker Center for Excellence to research and promote the benefits of oats. Candace Mueller Medina, a spokeswoman for the company's Quaker division, which makes a variety of products including oatmeal packets, bars and breakfast cookies, said the center's "first goal is to educate key opinion makers and influencers."
At the convention in Houston, Frito-Lay's booth displayed an ear of corn, a bottle of oil and a small bowl of salt in front of a bag of Fritos; the idea was to illustrate the simple ingredients used in its snacks. Nearby, a Frito-Lay employee explained to a packed class of dietitians during a 20-minute briefing how the company removed trans fats from its chips over the years.
"Another thing I like to remind people about is that not all our chips are that high in sodium," she said, noting that bread is the No. 1 source of sodium for Americans. Later, she invited them to try the company's new barbecue flavored chips.
Attendees earned a credit for sitting in on three such sessions.
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