There’s an old saying that breakfast is the most important meal of the day. Parents routinely implore their children to eat something in the morning so that they are energized, focused, and alert for school.

Increasing evidence suggests that breakfast does have many health benefits for growing children, including an improved overall dietary quality, and better concentration, attention, and memory.

Jianghong Liu, an associate professor in the School of Nursing, has found yet another benefit of eating an early morning meal: higher IQ scores.

In one of the first studies to examine IQ and breakfast consumption, Liu, along with Penn Nursing colleagues Barbra Dickerman and Charlene Compher, and Wei-Ting Hwang, an associate professor of biostatistics in the Perelman School of Medicine, examined data from 1,269 6-year-olds in China, and found that children who did not eat breakfast often had 5.58 points lower verbal, 2.5 points lower performance, and 4.6 points lower total IQ scores than children who regularly ate breakfast.

The researchers used information from Liu’s China Jintan Child Cohort Study, an ongoing prospective longitudinal analysis designed to assess the early health risk factors for the development of child neurobehavioral outcomes. Liu has been collecting data on children in the study—the oldest of whom are now 14—since they were 3 years old.

Liu, the lead author of the breakfast/IQ study, and colleagues collected information on children’s breakfast consumption habits by asking their parents how often their children eat breakfast in a typical week: “always,” “often,” “sometimes,” or “rarely.” Rice and noodles made up 69 percent of the breakfast meal.

When the children were in kindergarten, the researchers assessed their IQ using the Chinese version of the Wechsler Preschool and Primary Scale of Intelligence, a leading measure of cognitive ability for young children. Children who ate breakfast regularly had higher IQ scores, even when controlling for socio-demographic factors like a child’s gender, parental education, parental occupation, parental marital status, or whether a child resided in a city, suburb, or rural location.

“It does not matter what type of breakfast you eat,” Liu says. “As long as you eat breakfast, you have a better IQ.”

Liu says eating breakfast regularly had maximum benefit on the verbal IQ score. Breakfast provides an opportunity for young children to converse and interact with their parents, promoting cognitive and language development.

The key finding of the study suggests that breakfast consumption affects cognitive development in children. The researchers say that one possible explanation is that the overnight fast that occurs during sleep represents the longest period of fasting, and one important function of breakfast is to replenish low blood glucose levels. Glucose, Liu says, helps with overall brain function.

Eating breakfast consistently not only leads to a higher IQ score, but Liu says it also has long-term benefits on a person’s quality of life.

“If you eat breakfast regularly, you develop good habits, and it helps your long-term overall health,” she says. “Children who eat breakfast regularly are less likely to start other bad habits as teenagers, such as cigarette smoking, lack of exercise, and drug and alcohol abuse.”

Liu says both parents and schools can help increase breakfast consumption among children. She says parents can encourage their children to breakfast, and take them to the grocery store and pick out items they would like to eat.

“Give them a choice,” she says. “Prepare a variety.”

Liu says schools can assist by providing breakfast for students or a healthy snack such as granola bars, have teachers eat with the children to “create a culture” of eating breakfast, or even starting school later in the morning to give children more time to eat an early morning meal.

Since completing her study, Liu says she makes sure that her children eat breakfast everyday, and she has become a regular breakfast eater herself, even carrying around brown bags filled with early morning snacks.

“If you’re only allowed to eat one meal a day, eat breakfast,” she says.