Every few months, a new food fad comes along, whether it’s an ancient grain, tropical berry or some kind of algae. But in the advertising world, the hot new ingredient in packaged food is actually old and familiar.

Clearly, protein is being positioned as something women concerned about their weight may want to eat more of, but it's not just being marketed to women.

With protein being marketed to weight-conscious women and muscle-obsessed men, ads aimed at parents aren't far behind.

None of these ads make any literal claims about the health benefits of protein, and it turns out they don’t have to.

Research indicates that maybe because protein is a well-known nutrient, many consumers already believe it can provide more energy, help with weight loss by making us feel fuller, and promote muscle development in the young, while preventing muscle loss among aging Baby Boomers.

In the above ad, young newlyweds fuel their hiking honeymoon by eating Nature Valley Protein Bars.

But even more important to marketers than the specific perceived benefits of protein is the word’s "halo effect."

Regardless of how little consumers know about protein, the word seems to have a magic glow that causes consumers to believe products containing protein are somehow healthier.

The irony is that health authorities — such as the U.S. Centers for Disease Control — argue that, due to our high consumption of meat, North Americans already eat more protein than we need, which adds unnecessary calories.

But that doesn’t stop manufacturers from adding protein to almost every category of food and implying that we can all benefit from consuming more of it.