Can this brand be saved?

Coca-Cola has reigned for years as the world’s No. 1 brand, but last year both Apple and Google overtook it in Interbrand’s annual ranking. The first lady, Michelle Obama, is on a campaign against obesity, urging Americans to drink more water. Former Mayor Michael R. Bloomberg tried to ban sales of giant-size high-sugar soft drinks in New York City. And this week, the Food and Drug Administration proposed new food labels that would more prominently display grams of added sugar, including the high-fructose corn syrup used in Coca-Cola.

With the longstanding backing of the legendary investor Warren Buffett, Coca-Cola has been seen as the ultimate value stock, delivering steady returns in good times and bad. But last week, the company reported declining sales of soda in the critical North American market along with disappointing sales growth globally, alarming investors. Shares fell over 4 percent on the news, the most in seven months. So far this year, Coke shares have dropped nearly 7 percent, which is cataclysmic by Coca-Cola standards.

“Carbonated beverages are in precipitous decline,” said John Sicher, publisher of Beverage Digest. “The obesity and health headwinds are difficult and are getting stronger.”

It’s not just Coke that’s affected. By some measures, the Pepsi brand faces even bigger problems. But Coca-Cola is uniquely vulnerable, given that about 60 percent of its revenue comes from the sale of soft drinks, the bulk of it from Coke and Diet Coke.