New research from Australia has found that vitamin B levels significantly affect children's mental growth and happiness.

The study led by the Telethon Institute for Child Health Research found that children who had low levels of vitamin B in their diets had poor mental growth and these children were more likely to have behavioral problems.

Vitamin B can be obtained from fish, poultry, meat and dairy products. Leafy green vegetables, beans and peas too have vitamin B.

Vitamin B 12 is required by the body for proper blood cells production, maintaining brain function and for synthesizing DNA.

Carly Herbison, one of the study researchers, said that they found a direct link between low levels of vitamin B1, B2, B5, B6 and folate.

"B-vitamins are essential for the production of neurotransmitters, like serotonin, which modulates behaviour in humans and can contribute to feelings of well-being and happiness," she said.

The researchers analyzed medical records of people who had participated in the West Australian Pregnancy Cohort (Raine) Study. The study had records of diets including levels of vitamin-B intake. Mental health of the children was assessed using the Youth Self Report (YSR) that had scores for both internalizing behavior like depression and withdrawal and externalizing behavior like aggression and delinquency.

"Previous studies have shown that externalizing mental health and behavior problems developed during adolescence are related to a higher risk of offending and substance abuse later in life. What this study looked at was the relationship between diet, specifically B-vitamin intake and the presence of these externalizing behaviors," said Herbison.

The study is published in the journal Preventive Medicine.

"There is a great message in this in how diet may help prevent mental health problems. Improving what our children eat and ensuring they are getting essential B-vitamins from foods such as nuts, seeds, whole-grains, legumes and fruit and vegetables can have a really positive impact on their mental health and wellbeing," said Professor Wendy Oddy, senior author of the study.

"This research reinforces that to have good mental health, you need to have a balanced diet and 30 minutes regular exercise on most days. It's important to see good mental health as part of your overall mental and physical wellbeing, especially during the growth years," said Kate Carnell AO from Beyondblue.