Breakfast staple types affect brain gray matter volume and cognitive function in healthy children

Abstract

Childhood diet is important for brain development. Furthermore, the quality of breakfast is thought to affect the cognitive functioning of well-nourished children. To analyze the relationship among breakfast staple type, gray matter volume, and intelligence quotient (IQ) in 290 healthy children, we used magnetic resonance images and applied voxel-based morphometry. We divided subjects into rice, bread, and both groups according to their breakfast staple. We showed that the rice group had a significantly larger gray matter ratio (gray matter volume percentage divided by intracranial volume) and significantly larger regional gray matter volumes of several regions, including the left superior temporal gyrus. The bread group had significantly larger regional gray and white matter volumes of several regions, including the right frontoparietal region. The perceptual organization index (POI; IQ subcomponent) of the rice group was significantly higher than that of the bread group. All analyses were adjusted for age, gender, intracranial volume, socioeconomic status, average weekly frequency of having breakfast, and number of side dishes eaten for breakfast. Although several factors may have affected the results, one possible mechanism underlying the difference between the bread and the rice groups may be the difference in the glycemic index (GI) of these two substances; foods with a low GI are associated with less blood-glucose fluctuation than are those with a high GI. Our study suggests that breakfast staple type affects brain gray and white matter volumes and cognitive function in healthy children; therefore, a diet of optimal nutrition is important for brain maturation during childhood and adolescence.

Figure 1. Gray matter ratio of the rice group and the bread group.

The horizontal bars indicate gray matter mean ratio value in each group.

Figure 2. Gray matter regions with significantly larger volumes in the rice group as compared with the bread group after adjusting for age, gender, socioeconomic status, average weekly frequency of eating breakfast, and number of side dishes eaten for breakfast.

Significant regions are superimposed onto a brain surface of a SPM template brain, as well as onto axial images of the mean normalized gray matter segments derived from all the subjects. The left side of the image represents the left side of the brain. Color scales indicate the t-score. The number at the bottom of the right side of each image indicates the value of the z-axis in the Talairach stereotaxic space.

Figure 3. Gray matter regions with significantly larger volumes in the bread group as compared with in the rice group after adjusting for age, gender, socioeconomic status, average weekly frequency of having breakfast, and number of side dishes eaten for breakfast.

Details are the same as in Figure 2.

Figure 4. White matter regions with significantly larger volumes in the bread vs. the rice group after adjusting for age, gender, socioeconomic status, average weekly frequency of having breakfast, and number of side dishes eaten for breakfast.

Color scales indicate t-scores.