ADHD, or attention deficit hyperactivity disorder, is a common complain particularly prevalent in school children. "Meta-analysis of well designed studies that have examined the impact of sucrose on the behaviour of children produced no evidence that it has an adverse influence," concluded the professor. Benton looked in detail at a 2006 study (Lien et al) which suggested a possible role for sugar intake in modulating hyperactivity and conduct problems. Of 5498 Norwegian teenagers questioned, those who reported drinking more than four glasses of soft drinks per day were seen to have the poorest mental health. (Although those who consumed no soft drinks were seen to have slightly worse mental health than those who consumed average amounts). In addition, the higher the consumption of soft drinks, the more extreme symptoms of hyperactivity were observed. Crucially, however, Benton said that this should not be taken to signal a causal relationship. "This is particularly a risk when the possibility that diet affects the behaviour of children is discussed, in much of the population, the consumption of sugar and additives compete as the major causes of concern." Despite being aware that their study did not demonstrate a causal relationship, Lien suggested that sugar should be a "public health concern", according to Benton. But Benton believes this statement to be preemptive, and should await the demonstration of a causal relationship. Benton looked at evidence for the various mechanism by which sucrose would influence behaviour, such as food intolerance. "There are dozens of foods to which an adverse reaction has been demonstrated, although a reaction to sucrose is less frequent than many other foods." The second possible mechanism investigated was hypoglycaemia. Here, Benton found that in children who have a tendency to develop low blood glucose levels - although not so low as they can be clinically described as hypoglycaemic - also have a tendency towards irritability and violence. But he said that sucrose is not the main cause of swings in blood glucose levels. Benton said that parents report in studies that their child is distracted and fidgety an hour or so after eating sugary foods, but his analysis of the evidence pointed to parents seeing what they expected to see, not what is really happening. "The origin of the idea that sugar is responsible for hyperactivity seems to be purely based on the fact that sugar is a source of energy, as are other carbohydrates." Finally, Benton looked at studies into the role of sucrose on micro-nutrient status, since taking supplements of certain micronutrients has been linked to a decrease in anti-social behaviour. "Micro-nutrient intake is more closely associated with the total energy rather than sucrose intake," Benton said. The study is likely to be well received by the sugar industry. Benton's research was funded by The Sugar Bureau, but the author said that the grant did not direct or restrict the topics discussed. The role of diet in ADHD has come under the spotlight this year following the publication of the Southampton study, which found a link between consumption of certain cocktails of food colouring and the preservative sodium benzoate and hyperactivity in children drawn from the general publication. However despite the indication that sugar may not be contributing to behavioural problems in children, the food industry is still in the midst of a major reformulation of products to reduce levels of nutrients that can have an impact on health. As well as sugar, such nutrients unhealthy fats and salt. The main impetus behind the sugar reduction drive is the current obesity crisis. Statistics released by the UK's Department of Health in February said that in school year one (aged four to five), 22.9 per cent of children were seen to be overweight or obese. By comparison, in year six (aged ten to 11) 31.6 per cent were seen to be overweight. Excess consumption of salt and unhealthy fats have also been linked to increased risk of cardiovascular disease. Source Critical Reviews in Food Science and Nutrition DOI: 10.1080/10408390701407316 Sucrose and Behavioural problems Author: David Benton
A new review of studies investigating the role of sucrose in children's behaviour has concluded that it is not the root cause of behavioural problems such as ADHD.