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.In some families the need to aspire to better interpersonal communicationwithin the home and to provide more stimulus and activity for theirchildren is not recognized or accepted.Current sociological studiessuggest that communication between parents and children through,for example, speech and play is very important for optimal child devel-opment (Dietz 2001).Television is no substitute for this nor forimaginative play. What behavioural changes should take place? 99SleepSome studies suggest that children who sleep less are at above average risk ofobesity (Chaput et al.2006; Taheri 2006).This is an interesting finding whichcould have some significance for the present epidemic rise in childhood over-weight and obesity (Astrup 2006).There is little precise documentation but it isan impression that many children have less formalized bedtimes than in thepast.There are a number of possible reasons for this including the almost uni-versal presence of television and the fact that many children watch television,DVDs or videos, perhaps in their bedrooms, until late at night.A more relaxedapproach to child rearing with less structured parenting in this instance overspecified bedtimes may be another explanation.Parents who are working all daymay also want to spend more time with their children in the evenings than in thepast when mothers had often been at home with the children around them formost of the day and might perhaps have looked forward to child-free evenings.The physiological effects of sleep on weight control are independent of theobvious situation that if children are asleep they are not eating although boththis and reduced activity during the day due to increased tiredness couldcontribute to the effect (Taheri 2006).Short sleep duration leads to lower levelsof circulating leptin and higher levels of ghrelin.Leptin levels reflect thequantity of adipose tissue in the body and regulate energy balance within thebody by suppressing appetite and stimulating energy expenditure.Ghrelin isformed in the gastric mucosa and is elevated during hunger but falls on eating(Meier and Gressner 2004).It has almost the opposite effect on appetite to leptinthus adding to the effects of short sleep duration on appetite (Taheri 2006).There are no specific recommendations for children s bedtimes.Parentswho are trying to control their children s weights should consider taking afirmer line about bedtime and lights out.Maybe bedtime cannot be madeearlier than at present but perhaps it should be some time before it is madeany later.And bedtime should mean bedtime and not time spent playingwith gizmos in the bedroom.One aspect of child obesity prevalence which is difficult to explain is thevaried distribution of obesity across Europe.The UK has a prevalence whichis high compared with the Scandinavian countries but below that for much ofSouthern Europe (Lobstein and Frelut 2003).It is an impression that childrenin Southern Europe are often awake very late, eating with their parents at 10or 11 in the evening.Is obesity prevalent in these countries because manychildren have insufficient sleep? We do not know.TelevisionStudies in several countries, including the USA, the UK, Mexico, Thailand,New Zealand and Australia, have shown that the prevalence of obesity in a 100 What do we mean by lifestyle changes?study group correlates with the time the study children spend watchingtelevision (Robinson et al.1993; Gortmaker et al.1996; Hernandez et al.1999; Wake et al.2003; Hancox and Poulton 2006).The correlations betweenhours spent watching television and overweight may be more significant forgirls than for boys.In New Zealand, Hancox et al.(2004) estimated that timespent watching television was a more significant predictor of BMI than dietor physical activity.For young adults, watching television for more than 2hours a day contributed to greater overweight, higher serum cholesterol,more smoking and reduced fitness (Hancox and Poulton 2006).The epi-demic rise in childhood obesity in UK has roughly paralleled rises in thenumber of hours television programmes are available, the number of chan-nels available and the opportunities to watch DVDs and videos as well astelevision.To this we must now add the opportunities to view programmeson a wide range of equipments as well as the family television.Are all theserises in viewing opportunities coincidental or is television a very significantfactor in the development of an overweight population in the UK?Initial studies of adolescent American boys showed greater levels of obesityamongst those watching most television per week (Dietz and Gortmaker1985).These authors estimated that the prevalence of obesity amongst 12 17-year-old boys increased by 2% for every additional hour of television viewedper day.Time spent watching television could be displacing more activepastimes and encouraging snacking.High levels of television viewing seem tobe associated with greater consumption of high fat, high sugar, high salt(HFSS) foods in meals and snacks and less fruit and vegetables (Coon et al.2001; Coon and Tucker 2002).Any weight gain may relate more to the snacksconsumed than to low energy expenditure whilst viewing.Advertising ontelevision may also influence dietary habits, and meal skipping or rushingmeals seems more common in adolescents who watch more television (vanden Buick and Eggermont 2006).Further, television encourages sedentari-ness.The effect of television viewing on resting energy expenditure probablyvaries with individuals in that some may be much more at rest and sed-entary than others (Klesges et al.1993; Cooper et al.2006)
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