THE GREAT BREAKFAST DEBATE.

There's no meal like breakfast. No other meal has its own foods. For no other meal are people as likely to eat the same thing, day after day. No other meal's importance is hotly debated. * Thirty percent of Americans eat breakfast outside of the home. Of those, half take it to-go and nearly a third eat it in their cars. Fast-food outlets now serve two out of three restaurant breakfasts The "grab-and-go" approach has made it even tougher to find a healthy breakfast. From cinnamon rolls to sausage biscuits, from hash browns to bagels, most take-out breakfasts are nutritional nightmares. * This month, we take a closer look at breakfast. The bottom line: At [Illegible Text] or not you have breakfast matters less [Illegible Text].

"Breakfast is the most important meal of the day," goes the old adage. But do people really need to eat in the morning? The answer is clearer for children, but even with kids the research is incomplete.

The best evidence that breakfast matters comes from studies in which children are kept overnight in a lab and given tests within a few hours of either eating or not eating breakfast.(1)

"In laboratory studies on children, skipping breakfast after an overnight fast has adverse effects on tests that measure attention and the ability to discriminate among pictures that are relatively similar to each other," says Ernesto Pollitt of the University of California at Davis.

But not all studies agree, perhaps because they used different tests or different kinds of children.(2) "In the U.S. and other industrialized countries, kids who are poorly nourished are more likely to experience severe effects of skipping breakfast," says Pollitt.

Still, if there's any reason to think that breakfast improves learning ability, it's sensible for parents or schools to make sure that kids get it.

Adults are a different story. Whether or not they eat breakfast--83 percent do--may be less important than what they eat.

Memory & Thinking

Good studies testing the impact of a morning meal on the thinking ability of adults are few and far between.

"We have very little good data," says Pollitt.

A handful of studies--mostly on college students--has yielded inconsistent results. In some, breakfast didn't improve scores on tests of memory, reaction time, or tasks that require attention.(3,4) In others, breakfast boosted performance on some memory tests.(4-6) And one study found that breakfast lowered scores on a logical reasoning test.(4)

"A morning meal can impair some functions and enhance others," says Donna Korol of the State University of New York at Binghamton.

Korol and others are trying to find out whether eating breakfast may help older people perform better on some tests because it supplies blood sugar to the brain. That's why the only studies on seniors measured scores on tests given right after they consumed sweetened lemonade (which raises blood sugar) for breakfast. Lemonade improved some scores in some people, but the studies were too few, too small, and too inconsistent to reach any firm conclusions.(7,8)

And the results certainly don't mean that older people should drink lemonade for breakfast. "We can't say whether some other food would work as well," says Korol. "We don't know if the composition of the meal matters at all."

Weight Loss

One out of every two Americans is overweight. Does breakfast hurt their efforts to curb calories (because it means one more meal)? Or does it help, because famished weight-watchers who skipped breakfast might stuff themselves at lunch or at a coffee break?

"I can't give you a resounding: `If you want to lose weight, you must eat breakfast,'" says psychologist David Schlundt of Vanderbilt University in Nashville.

In a recent study, Schlundt told 52 obese women--16 who ordinarily skipped breakfast and 36 who usually ate it--to eat a 1,200-calorie diet for 12 weeks.(9) Each was randomly assigned to either a breakfast or no-breakfast group.

The people in the breakfast group ate less at lunch and dinner and were less likely to snack impulsively than those in the no-breakfast group. But breakfast didn't have much impact on weight loss. A change in routine did.

"People lost more weight if they usually ate breakfast and started skipping it or if they usually skipped breakfast and started eating it," says Schlundt. "If you want to lose weight, it's probably a good idea to change what you're doing because it makes you rethink your habits."

Other studies also suggest that skipping breakfast doesn't necessarily make people fatter. Though overweight people may be more likely to report skipping breakfast, that may just reflect their attempts to eat less.(10)

Despite the inconclusive evidence, Schlundt believes that it's a good idea for most people to eat breakfast. "Breakfast foods are easily made into a low-fat meal, and breakfast keeps many people from getting to the noon meal ravenously hungry, which may raise the chance of overeating."

Still, he adds, "you need to personalize a diet. A lot of people don't eat breakfast and do fine."

Healthy Diet

Breakfast-cereal-eaters get more vitamins, minerals, and fiber. They eat less fat. They're less depressed, less stressed, and even smarter than people who skip breakfast.

Thanks to funding from the cereal industry, especially Kellogg, studies have reported quite a list of benefits from eating breakfast. Some are just silly.

For example, it's quite a leap to assume that cereal caused cereal-eaters to score higher on reading tests or to report better mental health.(11,12) "People with higher incomes and education levels are more likely to consume healthy breakfasts," says Barry Popkin of the University of North Carolina. "There are clearly sociodemographic factors at work."

On the other hand, it makes sense that breakfast cereals--which are sometimes high in fiber and almost always low in fat and fortified with vitamins and minerals--cause many cereal-eaters to eat healthier diets.

"Cereal-eaters have the best nutritional profiles because of fortification, because of fiber, and because 98 percent of people eat them with milk," says Popkin.

But those findings don't mean that any breakfast has those benefits ... or that all cereals are equally healthful.

"You can't lump all breakfasts together and say `eat breakfast and you'll be healthy,'" says Popkin. "Some breakfasts are a heckuva lot better than others."

Using U.S. Department of Agriculture data (and funding from Kellogg), he grouped adults according to their breakfast-eating patterns:

* 22 percent ate bread, bagels, English muffins, or similar items (without eggs or cereal),

* 17 percent ate cold cereal (without eggs),

* 15 percent ate eggs (with or without bacon, toast, cereal, or other foods),

* 15 percent ate pastries (like doughnuts) and/or coffee or a soft drink,

* 6 percent ate just fruit or juice,

* 4 percent ate hot cereal, and

* 17 percent ate nothing.

Looking at what each group ate throughout the day, the egg-eaters and pastry-and/or-coffee-eaters did worst. They ate the most saturated fat and the least fiber.

People who ate cereals or fruit ate the least saturated fat. Cold-cereal-eaters also got the most iron and folate.

"Different breakfasts can make a vast difference to a person's health," says Popkin.

(1) Amer. J. Clin. Nutr. 67 (suppl): 779S, 1998.

(2) Amer. J. Clin. Nutr. 67 (suppl): 804S, 1998.

(3) Appetite 27:151, 1996.

(4) Appetite 22: 39, 1994.

(5) Biological Psychology 33: 207, 1992.

(6) Amer. J. Clin. Nutr. 67 (suppl): 772S, 1998.

(7) Amer. J. Clin. Nutr. 67 (suppl): 764S, 1998.

(8) Psychobiology 22: 95, 1994.

(9) Amer. J. Clin. Nutr. 55: 645, 1992.

(10) Euro. J. Clin. Nutr. 50:513, 1996.

(11) Psychological Reports 82: 424, 1998.

(12) Inter. J. Food Sci. Nutr. 498: 397, 1998.