Protein-infused bottled water. Ice cream. Boxed macaroni and cheese. Even vodka. The rise of weight-loss drugs is driving a boom in protein-based products, as users of GLP-1 medication like Novo Nordisk's (NOVOb.CO) Ozempic and Eli Lilly's (LLY.N) Mounjaro look for ways to counter the muscle loss those drugs can cause. GLP-1 users say they will spend 11% more on high-protein foods than before starting the drugs, according to an August survey from Boston Consulting Group.

Even as consumers seek out new sources of protein for their diets, they are becoming more skeptical of foods advertised as high-protein, Reuters interviews with consumers and company executives found. Some shoppers question whether products contain as much protein as advertising implies, while blanching at those that pack in so many additives or sugar that they undercut the health pitch.

A report from marketing research firm NielsenIQ earlier this year said the snack industry has entered its "accountability era," noting that 25% of its survey respondents this year said they are using scanning apps to check the nutritional value of products, up from around 17% last year.

"Protein is no longer a differentiator," said Chris Costagli, a lead marketing researcher at NielsenIQ, who co-wrote the report.

Megan Gisela Bautista, a nonprofit employee in Maryland who does strength training, was recently disappointed by the protein content of a chicken jerky snack that touted high protein in a large, colorful font.

"I'd have to eat five of them," Bautista said. "That's bad for you." Zack Spears of Dallas said he is checking nutritional labels regularly, and now watches YouTube videos from an online content creator who reviews protein-marketed products.

"As this protein craze pops off, and things are getting more expensive, I want to be sure what I'm putting in my body is healthy," Spears said. Some brands acknowledge the growing consumer scrutiny.

“Protein is here to stay, but the conversation must evolve,” said Susan Zaripheh, North America chief research officer for yogurt maker Danone (DANO.PA), in a statement to Reuters. “Consumers are starting to look ‘beyond the gram,’ becoming more informed in the nuances of protein source and nutrient density.”Over the summer, the French food company filed a false advertising lawsuit against rival yogurt maker Chobani, accusing it of inflating its protein claims on labels by using non-standard serving sizes. Chobani has disputed those claims, telling Reuters in a statement that its labeling is accurate and transparent.

Zaripheh said consumers want products that also aid in digestibility and contain other nutrients like fiber. In addition to existing high-protein yogurts and soy milks, the company is developing products that combine protein with other nutrients.

Globe Market Research estimated over the summer that the worldwide protein-enriched food market was worth nearly $58 billion last year.

But Hormel Foods (HRL.N), well-known for protein-heavy products like Spam and canned lunch meats, said it is avoiding the use of additives to increase protein in its products.

"We believe that in the long run, people don't want too much science in their food," said Jason Levine, Hormel chief marketing officer, referring to additives like "whey powder or pea powder or scientifically engineered protein isolates." Reuters found several brands that advertise protein content based on a larger portion size than used in regular versions of the same product, including in pastas, oatmeals and granolas.

Nature Valley, a snack brand owned by General Mills (GIS.N), sells a version of its “oats ‘n honey” loose granola that advertises 13 grams of protein on its packaging, based on a 2/3 cup (65 grams) serving size, more than twice as big as the 1/4 cup (27 grams) it calls a serving size for its regular, non-enhanced granola.

General Mills, in a statement, said it considers the regular version a snack while the protein version can be eaten either as a snack or a more complete cereal meal.

The product's protein-to-calorie ratio, a metric dietitians use to describe a product's protein content, indicates a “very low amount of protein overall,” said Jonathan Bonnet, a Stanford professor and chief medical officer at the Ardmore Institute of Health, adding that a glass of skim milk has more protein than the 2/3-cup serving. Bonnet said more patients are asking him lately for guidance on their protein intake.

Still, other companies are expanding their offerings to meet demand. Researcher Circana reported in August that around 48% of US adults are looking to add protein in their diets, up 7 points from last year.

Discount supermarket chain Aldi recently told Reuters it is launching a new line of private-label protein pancakes in October, the latest in a string of high-protein items released this year that have included sparkling water, crackers and wagyu beef jerky.

Walmart will start selling a new, protein-infused instant coffee product from J.M. Smucker's (SJM.N) Folgers from November until January exclusively, Walmart told Reuters last month.

Some consumers and dietitians say the protein trend has led people to eat more protein than they need.

NielsenIQ's report said a third of more than 1,000 surveyed respondents believe the food industry is overhyping protein — and another third believe some products have too much protein.

Dana Hunnes, a professor and clinical dietitian at UCLA, says the average person doesn't need as much protein as industry marketing has promoted.

And some protein-marketed products have too many processed ingredients to qualify as healthy, Hunnes said. “I’ve seen the equivalent of a candy bar” advertising protein, she said. “Just because it has protein doesn’t mean it’s something you should eat."