A study published last summer in Psychological Science shared a strategy that got preschoolers to voluntarily yes, voluntarily more than double the amount of vegetables they ate.

The strategy didn't include rewards or bribes or any degree of deception. What was the only thing the preschoolers were given to get them to eat more veggies?

Knowledge.

For about three months, a classroom of preschoolers heard stories during snack time that included information on the importance of dietary variety and the differences in food categories, the process of digestion, and the ways in which micronutrients and macronutrients nutrients affect the body.

A second classroom of preschoolers had snack time without hearing the nutrient stories and served as the control group. After three-plus months of hearing nutritional info, that group voluntarily ate more than double the vegetables at snack time than the group who didn't.

In short, the better informed preschoolers made better choices.

The same, I imagine, is true for teens and adults, so this research helped me to select this week's topic: The function of glucagon can get involved, however, so previously I had shied away from it.

But it's important knowledge that can keep your appetite from controlling you and allow you to control your diet.

Think of glucagon as insulin's opposite, a hormone that's far more familiar to most people.

You eat. After the food digests, your blood sugar rises. As a result, your body releases insulin into the bloodstream to escort the blood sugar along with protein broken down into amino acids to the cells of your muscle tissue. The first provides energy; the second permits muscle growth or repair.

Insulin is essential. Neither blood sugar nor amino acids can gain entry into muscle cells without insulin being present, so you'd die without insulin being secreted, so why does this hormone have such a bad reputation?

Because many people have bad eating habits, causing the hormone to be secreted in excess.

If you eat too many simple carbohydrates the type found in refined products like white breads, traditional pastas, pizza dough, cookies, cakes, crackers, and even dairy products your blood sugar becomes too high. Your body responds by increasing its secretion of insulin to such a degree that very little blood sugar is left in the blood, which leaves you feeling hungry even though you just consumed ample calories.

Moreover, your muscle cells can't handle large quantities of energy unless you've just finished a hard workout, so much potential energy is turned away. Insulin takes blood sugar rejected by the muscle cells to the fat stores.

So if you eat poorly, it's quite likely that about 90 minutes later (the timing is often a matter of how much protein, complex carbs, and fat were consumed along with the simple carbs), you'll feel hungry again even though you just added body fat.

Now consider the reverse.

What happens when insulin doesn't need to be released? What happens when you go three hours or so without eating anything (or many simple carbs) and your blood sugar level lowers to its baseline level?

Glucagon is released. Glucagon in the bloodstream allows stored body fat to be broken down and used as energy.

Glucagon is why working out in the morning on an empty stomach or working out twice in one day is so effective for weight maintenance or weight loss. Its secretion is also one of the reasons why low-carb diets can be effective.

It's also why if you can wait out that initial feeling of hunger, the sensation abates. That's because once glucagon has had its chance to break down body fat, your blood sugar level stabilizes.

That, at least, is what is supposed to happen. And that is what does for many people.

Except the obese.

Research released when it was accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology & Metabolism this summer determined that even though the obese secrete glucagon, it doesn't suppress their feelings of hunger.

While the researchers couldn't pinpoint why, they do know that even the study subjects with type 1 diabetes along with the lean ones reported a greater feeling of fullness after receiving an injection of glucagon after a meal a feeling that lasted up to 24 hours. The type 1 and lean subjects given a placebo did not report this feeling.

The injection of glucagon after a meal, however, had no effect on the obese subjects when compared to the ones given a placebo.

This study is significant. Too many overweight people assume that if they currently have no major medical maladies, like type 2 diabetes, being overweight only affects appearance. Nothing could be further from the truth.

The obesity epidemic is so new that no one really knows the ramifications. Studies like the aforementioned one intimate that being overweight for a protracted amount of time could fundamentally alter the body in ways that make losing weight more difficult.

So eat in a way that limits insulin secretion and promotes glucagon secretion in the hours afterwards. Limit your ingestion of simple carbs, and definitely avoid eating them in isolation.

Consume protein and complex carbs when you eat simple carbs, and they'll temper the deleterious effect the simple carbs have on your blood sugar.