BMC Public Health 2008, 8:103 http://www.biomedcentral.com/1471-2458/8/103 Background Preventing the development of obesity in children is an international health priority [1]. Current estimates suggest that the prevalence of overweight and obesity in all age groups is rapidly increasing worldwide [2]. In Australia approximately 25% of children are overweight or obese and that estimate is growing with data highlighting that these increases begin in early childhood [3]. An Australian sample of 114,669 pre-schoolers showed the prevalence of overweight and obesity increased from 16.3 to 27.2 per cent in girls and from 13.4 to 21.4 per cent in boys between 1995 and 2002 [4]. Overweight and obesity are recognised to have numerous negative impacts on children's health and wellness during childhood and through to adult life [5,6]. Further, research has shown that adiposity within the childhood period is a stable trait [7] and that parents are often poor at identifying fatness in their children [8]. In addition, obese children tend to become obese adults and treat- ment is difficult and costly [2]. Cochrane reviews have established that opportunities for prevention are poorly understood [9]. Overall there is an urgent need for research on the capacity to influence the development of children's obesity- promoting behaviours in early life. Overweight in early childhood is determined in part by eating, physical activity and sedentary behaviours learnt at home in the first five years of life. The intervention out- lined is informed by the understanding that (a) obesity- promoting behaviours are established early in life, (b) parents play a primary role in shaping these behaviours in infancy, (c) intervening before these behaviours (and par- ents responses to them) are established is likely to be effective, and (d) that the social milieu provided by parent groups is likely to facilitate and support the uptake of health promotion messages. Obesity-promoting behaviours are established early in life Recent evidence highlights that obesity-promoting dietary habits, such as high consumption of energy-dense foods and fluids, previously documented in children [10,11] are also evident in infants and toddlers [12]. Australian data using 3-day weighed food records (n = 538), shows 90% of 18-month old children consumed energy-dense snack foods on the recall days and 70% consumed sweetened non-milk drinks (e.g. soft drinks) [13]. Overall, foods considered as "extra" or "non-core" provided 27% of the total energy intake in that sample. In addition, the nutri- tional quality of diet is known to continue to decline throughout childhood and adolescence [14,15]. These early dietary patterns couple with evidence of high levels of sedentary behaviours in early childhood. For example, 17% of 0–11 month and 48% of 12–23 month old children in the US watch more than the recom- mended two hours of television per day, and this propor- tion increases throughout childhood [16]. Further evidence suggests that viewing television for more than two hours per day is positively associated with obesity- promoting dietary behaviours and low levels of physical activity in young children [17,18]. Little physical activity trend data during infancy and early childhood is availa- ble, however it appears that physical activity levels fall throughout this period [19,20]. In addition to population trend data, there is evidence of tracking of children's dietary [21], sedentary and physical inactivity behaviours [22] from childhood to adolescence and adulthood, which appear to impact on adult health [23]. Thus, the obesity-promoting behaviours learned and supported during these early years may establish lifestyle behaviours that will track throughout the lifespan. Given this, it is reasonable to posit that early childhood provides a unique and circumscribed opportunity within which to establish lifestyle behaviours that will promote health and minimize the risk of the development of obesity. The role of parents in the promotion of children's behaviours One of the most powerful predictors of weight manage- ment in overweight children is parental involvement, yet there remains an urgent need to examine opportunities to prevent childhood overweight and obesity via parental involvement in the early years [24-26]. Children's eating, physical activity and sedentary behaviours are learnt and sustained in the home and there is evidence that this envi- ronment impacts on children's weight [27,28]. Parents have the capacity via their nutrition knowledge, parenting style, modelling and the food environment to impact on children's emerging food choices [27]. Evidence has shown that in a young population (2–6 year olds, n = 564) the strongest predictor of children's fruit and vegeta- ble consumption was parent consumption [29]. In addi- tion, child rejection of fruits and vegetables (negative association) was modifiable with repeated exposure to rejected foods. In terms of parents' involvement in physical activity with their children, one study reports that parents spend 13% of their child's play time in active play with their infant and that the remainder of time is spent in object play [30]. The use of parks and outdoor spaces is reported by less than half of parents with 5–12 year olds [20]. Children whose parents are active with them are reported to have higher levels of physical activity [31,32]. However, family rules are reported to be inversely associated with chil- dren's physical activity [26]. Similarly, rules prohibiting television viewing during mealtimes are reported to be inversely associated with children's television viewing Page 2 of 9 (page number not for citation purposes)