Though diet studies disagree about what's worse for you, carbohydrates or fat, most say nice things about eating protein, including its potential for better weight control.

US consumers have taken note, and so have food manufacturers and restaurant chains. More than a dozen companies have introduced new products or meals that are "enriched" or "fortified" with protein in the last few years, and the protein push is accelerating.

In July, Taco Bell started selling high-protein meals, which contain Greek yogurt options and twice the meat as in its traditional burritos and bowls. In May, General Mills Inc introduced protein-enriched Cheerios, which provided a bright spot at its Wednesday earnings call. In February, Kraft started selling a "protein pack" with meat, cheese and nuts.

Protein has so far scored a big win for the companies, which are looking for new ways to beef up their profits as sales of traditional prepared foods slip and consumers seek healthier and fresher food options. The trend also has been a boon for the mostly Canadian "pulse" industry, which provides the dried seeds of peas, chickpeas, beans and lentils used to fortify many of these products.

Whether these protein-enhanced products are actually healthier is another question. Soy, lentil and pea powder - extracted from those legumes and used in everything from pasta to milk - are, in fact, good sources of protein similar to steak or eggs, nutritionists said. But many of the products they are delivered in, such as granola, cereal and breakfast bars, are often high in fat, salt or sugar.

Besides, most Americans already get almost twice the daily protein they need. The average American consumes 79 grams a day of protein, but men only need 56 grams and women 46, according to the United States Department of Agriculture.

"Protein is not deficient in US diets," said Marion Nestle, professor of nutrition and public health at New York University. "This is about marketing."

Some studies have said that because eating foods high in protein makes people feel fuller sooner, they tend to eat less and may be able to control their weight better. On the other hand, eating too much protein can lead to kidney disease, cancer and osteoporosis, while adults who eat diets high in animal protein are four times more likely to die of cancer and diabetes than those with low-protein diets, according to a March 2014 study published in the journal Cell Metabolism.

To be sure, people would need to consume at least twice their recommended daily amount to potentially suffer serious health consequences, according to the USDA. The recommended amount is 0.8 grams per two pounds of weight, or 80 grams a day for a 200-pound man.

"Consumers think of protein as a hard-working calorie," said General Mills Chairman and CEO Ken Powell in an interview with Reuters. That is fueling demand for everything from protein bars to Greek yogurt, he said. "It's clearly an opportunity."

As the food industry scrambles to meet the demand, the effect has been felt along the supply chain, especially in Canada where most of the ground protein for US food-makers is produced.

Canada produced a record six million tonnes of pulse in 2013, up from 4.5 million tons in 2012 and 4.3 million tons in 2011, according to Pulse Canada, an industry association that represents Canadian growers and processors. Privately-held Best Cooking Pulses Inc in Portage la Prairie, Manitoba, has quadrupled its capacity in the last year, and opened a second plant to process the seeds.

"I see it being a fantastic opportunity," said Murad Al-Katib, president and CEO of Alliance Grain Traders in Regina, Saskatchewan, one of the world's largest lentil and pea processing companies. "Where we're seeing a lot of that growth is new product lines from major food companies."

BANKING ON PROTEIN

Food makers are eager to find new sources of revenue. Consumption of carbohydrate-laden foods has fallen 5 percent in the United States while consumption of protein-rich foods has risen seven per cent, according to a recent report by Credit Suisse investment analyst Robert Moskow.

Protein is becoming ubiquitous: It's piling up in extra meat servings at fast food restaurants and in everything from cereals to biscuits to cream cheese.

Dairy companies are even adding protein to milk, which already has about 8 grams per serving. Shamrock Farms, a Phoenix-based milk producer, began selling its "Rockin' Refuel" muscle building milk in 2009 with added protein. The company is now expanding the line with additional sizes and flavors because of double digit sales growth.

Food makers also are repackaging existing products to appeal to protein seekers. For example, Kraft recently began selling its "P3 Portable Protein Pack," which features its Planters peanuts, Oscar Mayer luncheon meats and Kraft cheese in one package.

The company said the P3 is "one of our big bets" for 2014. It has "helped our business attract new consumers," said Kraft spokesman Basil Maglaris, who wouldn't provide sales numbers.

General Mills, which Wednesday reported lower-than-expected quarterly profit, is counting on its protein-fortified snacks and expanded Yoplait Greek yogurt line to boost profits.

It plans to expand distribution of its recently introduced Cheerios Protein, fortified with soy and pea protein, which at 26 cents an ounce costs significantly more than the 19-cents an ounce traditional oat Cheerios.

Its Nature Valley protein bars, introduced in 2012, made over $100 million in sales in their first year. Its Yoplait Greek yogurt line, which contains twice the protein as generic yogurt, debuted in 2012 and in its first year netted $150 million in sales.

Morningstar equity analyst Erin Lash said these are impressive figures considering that 81 percent of new consumer packaged goods failed to hit $7.5 million in first-year sales in 2011.

General Mills is counting on consumers like Maryland college student Madeleine Entwistle.

"I'm cautious about the food I eat," said the 20-year-old, who said she eats a couple of its Nature Valley protein bars a day.

"I would expect that it costs more because it has more nutrients. But I associate the foods as being better for me." - Reuters