It’s an oldie, but a goodie.

Published about a dozen years ago in Nutrition Research, the study took 21 males ranging from 21 to 70 years of age and fed them breakfast twice with a one-week break in between. The breakfasts totaled the same number of calories, but one was “bagel-based,” high in carbohydrates, and low in fat; the other was “egg-based,” low in carbs, and high in fat.

If a subject ate the bagel-based meal the first time, he ate the egg-based one the next time.

But before any eating was done, researchers took blood samples from all in a fasted state after a night of sleep. Blood samples were also taken 30, 60, 120, and 180 minutes after each breakfast.

Every time blood was drawn, the participants evaluated their hunger and appetite by following a widely used rating system, known as VAS or Visual Analogue Scales. Based on this, subjects were determined to be hungrier and less satisfied three hours after the bagel-based breakfast when compared with the egg-based breakfast.

Once the last blood samples were taken, the 21 males were served a buffet lunch and asked to eat until satisfied.

Those who ate the bagel-based breakfast consumed more cals at the buffet lunch.

They also ate more food over the next 21 hours, and the blood samples suggest why. Whether the blood was drawn 30, 60, 120 or 180 minutes afterwards, the bagel-breakfast eaters had higher blood sugar and insulin levels.

Equally as important, each blood sample taken showed the egg-breakfast eaters had a “suppressed ghrelin response.”

Ghrelin: It’s the topic for today because of the hope I have for you and shared to conclude last week’s column. That you read all you can about health and fitness, give it great thought, intelligently experiment as a result, and by doing so enhance your overall health.

Knowing more about ghrelin can only help this process.

It’s called the hunger hormone and rightfully so. First discovered in 1999, ghrelin is the only known substance produced by the body that stimulates appetite.

In fact, when it’s used for medical purposes, it increases food consumption by up to 30 percent, according to the Society of Endocrinology. When your body secretes it, it seems to do the same as well.

Consider what happened to the 147 type 2 diabetics in a diet study led by Dr. George Thom at the University of Glasgow and published in the December 2020 issue of Diabetes, Obesity & Metabolism. They lost an average of 14.3 percent of their body weight in five months, but by the conclusion of a weight-management program 17 months after that, nearly half of all weight lost had been regained.

The dieters who regained the most weight also had the highest levels of ghrelin in the blood samples taken during those 17 months.

Thom concludes the paper by calling a “significant compensatory drive” to weight loss and a “predictor” of weight gain.

But does it have to be? Not according to a 12-month case study of a 26-year-old male bodybuilder published in the September 2013 issue of the Journal of Sports Physiology and Performance.

During an intense six-month regimen of strict dieting and demanding weightlifting, he dropped his body fat percentage from 14.8 percent to 4.5 percent. Just to be clear here, he dropped 70 percent of his body fat in 180 days.

Yet during this time, his production of ghrelin - the only hormone know to increase appetite - increased by 40 percent.

While you may not have the steely resolve and ironclad will of a devoted bodybuilder, there are ways to limit the increase in ghrelin production that results from dieting, as well as the potential “compensatory” effects. And they’re just common-sense health tips I’ve suggested in the past.

Get enough sleep

Remember all those past articles about how a lack of sleep increases the odds of weight gain? Multiple studies have found a less-than-sufficient amount of sleep not only increases ghrelin production, but it also decreases the production of leptin, the hormone seen to be ghrelin’s opposite since it leads to a sense of satiety.

Eat a diet high in protein

Remember all those past articles about how a diet of predominantly protein and complex carbs keeps you feeling full? That’s in part because numerous studies have linked high protein and fiber ingestion with an increased feeling of fullness and a reduction in hunger.

Some studies, however, have found some high-protein meals don’t actually reduce ghrelin production, so it’s possible the real benefit to increased protein ingestion is a suppression of ghrelin’s normal effects.

Lift weights

Remember all those past articles about how weightlifting boosts your metabolism, mood, and energy level; strengthens your muscles and bones; and helps prevent mobility problems, heart disease, type 2 diabetes, and certain cancers? Add another benefit to the list.

A body with more muscle and less fat produces less ghrelin.