Restricting food intake - does it promote or protect against child overweight?
By Dr Karen Campbell from the Centre for Physical Activity and Nutritional Research
It has been proposed that restricting children’s food intake is likely to promote unintended eating consequences whereby restricted foods become more favoured and in turn, will be over-consumed when the restriction is removed. A likely consequence of over-consumption of palatable foods is increased body weight.
The message that parents should not restrict their children’s access to energy-dense foods and drinks may be construed to suggest that parents should make such foods freely available. Indeed, the uptake of this message at a public health level may have negative consequences for child weight. Given that increased food availability is a well-described correlate of increased consumption this would be cause for concern. For example, child and adolescent soft drink consumption is higher in homes where soft drink is freely available. Further, Corsini et al.have reported that the association between restriction and eating in the absence of hunger may be moderated by the availability of palatable foods in the child’s environment, such that restriction is associated with eating in the absence of hunger only when availability is also high. To reduce children’s intake of energy dense foods and drinks from current levels (>30% of daily energy intake in Australia) to be in line with recommendations (5–20% of daily energy intake) may actually require public health strategies that target consumption of these foods directly.
This study is one of four to provide a longitudinal assessment of the association between parental use of food restriction and child body mass index (BMI). It examines associations between parental feeding restriction at baseline and child body mass index (BMI) z-score three years later. In this studyparents of 204 5–6 year-old and 188 10–12 year-old children completed the Child Feeding Questionnaire at baseline (2002/3). In 2002/3 and 2005/6, children’s BMI z-score was calculated from measured height and weight.
We found that baseline parental feeding restriction was associated with follow-up zBMI at three years in the 5–6 year old children such that parents who reported more actively restricting the food they provided had children with smaller increases in zBMI. This was not found in the older children.
The findings of this study challenge the view that restricting children’s energy-dense food and drink intakes is detrimental and suggests that such restriction may be protective of increased BMI in younger children. Indeed, the evidence to date suggests that the influence of parental feeding restriction on child BMI is, at minimum, benign and is not sufficient to support the notion that restriction of energy-dense foods for children is inappropriate.
This study highlights that we may need to clarify what is meant by food restriction and to better assess how restriction may impact on children’s dietary intake and subsequent body weight. All restriction of food may not be the same, and may impact on a child’s intake in different ways. It is mooted for example that food restriction may be either overt, whereby the child’s intake of unhealthy foods is limited in a way that can be perceived by the child (for example, a restricted food is eaten by the parent in view of the child; a food is accessible in the home but not allowed to be consumed), or as ‘covert’ where food is restricted without the child being aware that this is happening (for example, a food is not brought into the home; a child is not taken to the lolly shop). To date we remain unclear whether these different kinds of restriction may affect a child and his/her consumption and potentially increase body weight. This remains an important area for future research.
1. Corsini N. Exploring aspects of parental control over feeding: influences on children’s eating behaviour and weight. Adelaide: University of Adelaide. 2008.
2. Birch LL, Fisher JO, Grimm-Thomas K, Markey CN, Sawyer R, Johnson SL. Confirmatory factor analysis of the Child Feeding Questionnaire: a measure of parental attitudes, beliefs and practices about child feeding and obesity proneness. Appetite. 2001; 36(3): 201-10.
3. Ogden J, Reynolds R, Smith A. Expanding the concept of parental control: a role for overt and covert control in children's snacking behaviour? Appetite. 2006; 47(1): 100-6.
Campbell K, Andrianopoulos N, Hesketh K, Ball K, Crawford D, Brennan L, Corsini N, Timperio A. Parental use of restrictive feeding practices and child BMI z-score: a three year prospective cohort study. Appetite. 2010;doi:10.1016/j.appet.2010.04.006.
Victorian Health Promotion Foundation, National Health and Medical Research Council and National Heart Foundation of Australia.