You won’t believe what it is.

A new study has shown that eating fruits and vegetables on a healthy basis can improve a person’s mental well-being. The study was taken on children and the researchers noted each child’s meal choice and the overall consumption of fruits and vegetables for each child.

The study found that higher consumption of fruits and vegetables were associated with higher mental health scores for children. The study also took into account each child’s living situation, ethnicity, age, adverse experiences and disabilities.

Study co-author Prof. Ailsa Welch stated that “In a class of 30 secondary school children, we found that [four] had nothing to eat or drink before starting classes in the morning, and [three] had nothing to eat or drink before the afternoon. Only 25% of children ate [five] or more fruits and vegetables a day, and 1 in 10 ate none.”