Childhood obesity is bad news for heart disease in the future
Apart from stating the obvious, we are in big trouble. Health services costs are rising and we can’t afford it. There are no new drugs to counteract the growing increase in chronic disease which cost us a fortune. Yet, to counteract all this we are getting fatter and fatter, and presenting a future steeped with dire consequences for our children.
Results from 63 studies of 49,220 children aged 5 to 16, published in today’s BMJ by our group, starkly illustrates the effect obesity has upon increasing risk of cardiovascular disease for future generations of children. We know that being overweight in adulthood increase your risk of heart disease and stroke, we now know that for children, these very same risk factors are increased markedly at a very young age.
Obese children have a blood pressure greater by 7.5mmHg than normal weight children. This rises to 11.5 mmHg when the more accurate ambulatory blood pressure readings are used. The increase seems to be greater for girls than boys: but the reason for this additional increase is unknown. Also, other important risk factors for heart disease are raised in obese children: blood lipids (cholesterol and triglycerides) are raised; fasting insulin and insulin resistance are worse and the left ventricular mass of the heart is increased when compared to normal children.
Being overweight as a child corresponds to a Body Mass index (BMI) of 25 to 30 and obesity as a BMI of over 30. BMI is a number calculated from a child's weight and height, and is weight in kg divided by height in metres squared (kg/m2). Although BMI does not measure body fat directly, it correlates with accurate measures of body fat, such as underwater weighing, and can be used as a simple measure for screening children.
Many countries use reference points in children to classify obesity, taking into account age, sex and a reference population. Whilst this data calculates an average for the population, and classifies obesity according to the degree of variation from this mean it may mask worrying trends due to increasing average weight of children over time. In 2007, the US obesity rates have nearly quintupled among 6- to 11-year-olds since the 1970s. Worryingly, in the UK school year, 2010/11, one third of children aged 10 to 11 were overweight or obese.
Like climate change, we know the problem is coming, but because the effects are at some point in the future, we are burying our heads in the sand, hoping the problem might just go away. For what is an easy situation to prevent: we need concerted action now. Jamie Oliver, once said "we're losing the war against obesity," We may have already lost it: 1 in 3 adults and 1 in 6 children are currently obese.