Keep kids moving
A chubby child is at risk of growing up to be a sick adult, and the first cardiometabolic changes can already be observed in childhood. Another concern is that overweight often goes hand in hand with immobility, which may lead to poorer achievement at school.
"We need to identify those at risk and introduce lifestyle changes early on," says Professor Timo Lakka of UEF's Institute of Biomedicine.
The Physical Activity and Nutrition in Children (PANIC) study, led by Professor Lakka, has shown that poor nutrition and lack of physical activity take their toll at an early age.
"We have observed higher insulin and glucose levels, abnormal blood lipids, raised blood pressure and other cardiometabolic risk factors in children as young as 6 to 8 years of age, and they often accumulate in overweight children."
Children can hardly be blamed for gaining weight and putting their health at risk – it's parents who buy the groceries and decide on meal times. However, less than half of the children participating in the study ate all three main meals – breakfast, lunch and dinner – every day.
Those who skipped main meals were more likely to have excess body fat and an increased cardiometabolic risk, partly because of replacing proper meals with unhealthier snacks. According to Aino-Maija Eloranta, who presented the results in her doctoral thesis, the lack of regular mealtimes may also trigger overeating in children with poor eating control.
"It's natural for children to be physically active, but today's society is geared towards sedentary behaviour," Professor Lakka says.
Indeed, the Internet, smartphones, mobile games, social media and TV are an important part of many children's lives. Walking or riding a bike to school would offer a chance for daily exercise, but many children travel to school by car or bus.
In the PANIC study, Researcher Juuso Väistö found that lower levels of physical activity and higher levels of sedentary behaviour were clearly linked to a higher cardiometabolic risk score and body fat percentage, even independent of diet. Lots of time spent on electronic media increased the risks, even in children who were physically active.
Another new finding was that just like type 2 diabetes and cardiovascular diseases, fatty liver disease may be linked to childhood obesity and other cardiometabolic risk factors. In her doctoral thesis, Anna Viitasalo observed that a common mutation in the PNPLA3 gene, associated with fatty liver disease in adults, resulted in raised liver enzyme values in childhood – in overweight children. A total of 41% of the children in the study were carriers of the mutation, and 15% were overweight.
Another reason to keep children moving is that physical activity can improve academic performance. Eero Haapala's doctoral thesis showed that higher levels of physical activity are related to better literacy and numeracy skills in the first three school years, especially among boys. Boys who walked or cycled to and from school had better reading skills than less active boys. Poorer motor performance was linked to poorer literacy and numeracy test scores.
"We hope to be able to get financing for brain imaging studies at Kuopio University Hospital to look into some of the mechanisms by which physical activity and motor performance affect cognition. At the moment, these mechanisms are only partly known. Increased brain plasticity or humoral cross-talk between skeletal muscles and the brain may be involved," Professor Lakka says.
A vicious circle may develop when poor motor skills discourage a child from being physically active, possibly leading to poor neuromuscular and cardiovascular fitness, obesity, and even less exercise. On the other hand, results from the study suggest that the circle can be broken and lifestyle-related risks are reversible. A physical activity and diet intervention carried out in the study will serve as a model for schools and healthcare professionals to better identify and help children at risk.
Text: Ulla Kaltiala Photos: Varpu Heiskanen
How much physical activity does a 7-year-old need?
At least two hours a day: organized exercise, outdoor games, commuting by bike or on foot, or other physical activities. No more than two hours of continuous sitting. A maximum of two hours of passive screen time per day.
Diet checklist for chubby kids' parents
Stick to regular meals. Don't keep sugary drinks and junk snacks available on a daily basis. Provide vegetables, but not red meat at every meal. Use vegetable oils and regular-fat vegetable-oil margarines.
Hyperactivity may reveal sleep-disordered breathing
Specialised dentist Tiina Ikävalko found that one in ten children in the study snored or had nocturnal pauses in breathing, linked to enlarged tonsils, crossbite and convex facial profile, as opposed to its link with excess fat in adults. Daytime hyperactivity and learning difficulties can be signs of this treatable disorder.
The multidisciplinary PANIC study
The study assessed the lifestyle, health and well-being of a representative population sample of 512 children aged between 6 and 8. Half took part in a lifestyle intervention with their families. The 8-year follow-up will start by the end of 2015.