<a href="mailto: pzekman@cbs.com; mhlebeau@cbs.com; dlblom@cbs.com" target="_blank">Send Your Tips To Pam Zekman</a>By Pam Zekman

(CBS) — People trying to watch their salt intake know it’s tough to figure out what is good or bad to eat sometimes.

But you’d think food products with the American Heart Association’s “Heart Check” endorsement would be good for you, right?

CBS 2’s Pam Zekman reports you might be surprised.

Campbell’s soup cans with the “Heart Check” certification have 410 mg of salt per serving for their “Healthy Choice Soup.”

“It’s not heart healthy in terms of sodium, absolutely not,” says Dr. Christy Tangney, a nutritionist at Rush University Medical Center.

Shoppers were surprised as well when Zekman showed them the sodium content listed on the label on the back of the can.

“Wow,” said Daniel Savage, who has to watch his sodium intake because of a medical condition. “Four hundred and ten milligrams. That’s terrible.”

The 410 mg of sodium per serving is less than the FDA maximum for healthy foods, but more than a recommended amount listed on the AHA’s website for low sodium — 140 mg.

“It can be a big difference, particularly for those people most at risk,” Dr. Tangney says.

Another problem is the sodium content listed on the soup cans is for one serving only. That’s half the can or one cup.

Dr. Tangney says consumers are likely to have the whole can, which means 820 mg of salt.

A class-action lawsuit has been filed against the Campbell Soup Company and the American Heart Association.

“It’s a breach of the public trust,” said Adam Levitt, one of the attorneys who filed the case in the U.S. District Court in New Jersey.

The lawsuit seeks to change the soup-can labeling and compensate those who bought the soup under false pretenses.

“This is not a food-police kind of lawsuit,” Levitt said. “The issue here is about whether a major, major food company in the United States, as well as a leading heart health organization, can lie to the American public.”

In a videotaped response, the chief science officer for the American Heart Association said the organization will fight the lawsuit.

“The claim in the lawsuit is inaccurate and false and it’s not even plausible,” said Dr. Rose Marie Robertson. “Our ‘Heart Check’ mark helps consumers make smarter choices about the foods they eat. It is not deceptive or misleading.”

Says Dr. Tangney: “If you don’t look at the back of the label it is misleading — definitely.”

The AHA’s Science Officer also said the “Heart Check” criteria and AHA’s general nutritional guidance are both available to the public.

In a written statement, the organization emphasizes it recommends an average of 1500 mg of sodium or less per day. And not all foods must be low sodium to fit in a heart healthy diet.

A spokesman for Campbell’s Soup said the company believes the allegations in the lawsuit are without merit and their labels and marketing comply with all legal and regulatory requirements.

Here are more detailed responses from the American Heart Association to questions from CBS 2:

Why does the American Heart Association give heart check certification to products that do not follow its own low sodium dietary guidelines of 140 mg per serving?

The American Heart Association does not have a universal “low sodium dietary guideline” of 140 mg per serving.  The American Heart Association recommends that people aim for an average daily sodium intake of 1500 mg or less of sodium per day, as part of an overall healthy diet, unless their healthcare provider suggests otherwise.  The American Heart Association encourages consumers to choose low- and reduced-sodium foods as one part of their efforts to improve their diet, since the average American diet is excessively high in sodium.  Not all foods must be “low sodium” to fit in a heart healthy diet.  Products in some food categories, like soup, can qualify for Heart-Check certification if they contribute to an overall healthy diet and contain fewer than 480 mg of sodium per standardized serving.  The Heart-Check program’s criteria are based on sound science and are consistent with FDA and USDA regulations.  The Heart-Check program’s nutritional criteria are available here.

Is this misleading to consumers who suffer from high blood pressure, hypertension and other heart- related conditions who are looking to the AHA heart check food certification for guidance on what to buy that is heart healthy? 

No.  The Heart-Check program is not a dietary solution targeted at a particular condition or disease, and makes no therapeutic claims.  The program is designed to help the public make informed choices about the food they purchase, and is useful to those seeking to make healthy food choices.  Those with a medical condition, such as high blood pressure, heart failure or other disorders should follow their healthcare professional’s advice.  Reading the food label is always important, especially when treating a particular condition, even if the product displays the Heart-Check mark.