Most seven and eight-year-olds in Ireland are considered very healthy by their parents, however 20% are overweight or obese and many are spending too long on screens, a new report has found.

Growing Up in Ireland: The National Longitudinal Study of Children has been monitoring the development of nearly 20,000 children since 2007 - over 11,000 children who were nine-month-olds at the outset and more than 8,500 children who were nine-year-olds.

According to its latest findings, around 80% of children aged seven and eight were described by their parents as very healthy. However, 15% were reported to be overweight, while 5% were reported to be obese.

Excess weight was more common in low income families, with 27% of children aged seven and eight from the lowest income families described as overweight, compared to 16% of children from the highest income families.

Furthermore, 36% of children from the most socially disadvantaged families had a low-quality diet compared to 17% of children from families with a professional/managerial background.

When it came to socio-emotional development most children were found to be doing well, with girls scoring higher than boys when it came to certain social skills, such as empathy and self-control.

Based on reports from the children's mothers, reading, make-believe games and playing on a tablet/computer were the most frequent types of play that seven and eight-year-olds took part in.

While 35% of children read for pleasure every day, 22% did so less than once or twice a week. However, all children typically spent one to two hours per day on a screen, and at the weekend, this increased to over three hours per day.

Boys tended to be use screens more often than girls and on a typical weekend day, 51% of boys and 39% of girls spent more than three hours on screens.

The report noted that children whose mothers had lower levels of education had more screen time. Some 23% of seven and eight-year-olds whose mothers were educated to Junior Certificate level spent three or more hours on a screen on a week day compared to 6% of children whose mothers had a degree.

When it came to school, children who found it difficult to settle in at the beginning, continued to find it difficult at ages seven and eight. Boys were more likely than girls to find school difficult and children whose mothers had less education were more likely to find schoolwork difficult.

"The findings highlight the importance of early identification and intervention for children who have a negative attitude towards school from their earliest experiences of it.

"Negative attitudes towards school at five years of age are reflected in the children having difficulties in adjusting to school twe to three years later and to coping with the pace of schoolwork," commented James Williams, a research professor at the Economic and Social Research Institute (ESRI), which published the report.