four groups. One group served as the control, while children
in the other three groups each received a porridge made up
of corn, beans, and greens every morning for breakfast. One
group received the mixture with a glass of milk, another had
ground beef added, and the third got just the plain-Jane
version. All versions were balanced to contain the same
number of calories, and the study ran for two years.
Compared with the other groups, students in the meat
group gained more muscle mass and had fewer health
problems than the children who consumed the porridge
plain or with milk.^3 They also showed greater confidence in
the playground—a sign of improved mental health.
Cognitive performance was stronger too. While all groups
improved, the meat group showed the steepest rate of
improvement in math and language subjects. Neumann and
her colleagues wrote:
The improved cognitive performance and increased
physical activity and leadership and initiative behaviors
in the meat group may be linked to greater intake of
vitamin B 12 and more available iron and zinc as a result
of the presence of meat, which increases iron and zinc
absorption from fiber- and phytate-rich plant staples.
Meat, through its intrinsic micronutrient content and
other constituents and high-quality protein, may
facilitate specific mechanisms, such as speed of
information processing, that are involved in learning.
This study was performed in children, but we now know
that our brains continue to change throughout life—