On Saturday night I was on a plane winging me back to the UK from Kenya where I’ve been for the last week. I was perusing the in-flight magazine and came across an ‘advertising promotion’ for a company making soft and ‘sports’ drinks. The promotion featured some Q and A’s with a UK GP on matters such as hydration and caffeine. There was also a question about the effect of sugar on dental health. I’m embarrassed to say I don’t remember the precise question and answer (fatigue, I suspect, has something to do with this). What I do remember is thinking that when thinking about the effects of sugar, we need to think beyond any damage it can do to the teeth.
I suspect this thought was at the forefront of my mind as earlier that day I had been reading a story on BBC News about the potentially corrosive effects of fruit juices and squashes on the teeth. The story drew our attention not only to the fact that sugar can lead to dental decay, but that the acidic nature of these beverages can lead to erosion of tooth enamel. Again, when I was reading this, I was thinking about focusing on dental health only tells part of the story about why fruit juices and soft drinks should be, generally speaking, avoided by those that value their health and wellbeing.
For instance, fruit juice consumption has been linked with enhanced risk of weight gain in children, and so has (obviously) the drinking of soft drinks.
The effects of fruit juices and soft drinks in the mouth and deeper within the body mean that I don’t generally recommend them for children (or adults for that matter). So what should we be recommending that our children drink? Well, perhaps as expected, the BBC News article concludes by promoting milk and states that: milk in the diet helps the formation of strong teeth and bones.
But do these ‘facts’ stack up? The role that calcium and dairy products play in bone-building was reviewed most recently in the journal Pediatrics [1]. Of 37 relevant studies 27 found no relationship between dietary calcium or dairy product intake and measures of bone health. Of the remaining studies, any apparent benefit was small.
Further evidence for the limited role of dairy products in building bone has come from a study published in the British Medical Journal which amassed evidence from 19 studies in the effects of calcium supplementation in children ranging from 3-18 years in age [2]. This mass of evidence found that calcium supplementation had no effect on bone density in the hip or spine, and very marginal benefits for bone density in the arm.
And what of the effects of milk on teeth? I’m open to the idea that drinking milk is likely to be better for teeth than soft drinks and fruit juices, but I wonder how important it is for healthy dentition. Archaeological remains show that up to about 10,000 years ago, human dental health was generally good (dental problems emerged, it seemed, with the addition of grains to the diet). It is believed that it was only until about 5000 years ago that we started to consume dairy products. This date may be a little out. But even if it is wrong by a few thousand years, the fact remains that for the vast majority of our time on this planet we managed to build strong teeth (and bones for that matter) without the need to consume dairy products from other animals. This basic fact causes me to have grave concerns about the supposed importance of milk in dental health.
I quite often hear from parents that their children ‘refuse’ to drink water. So they often end up giving them fruit juice, squash or whatever instead. What this means is child is now dictating what they drink. I’m a liberal at heart (honest) but this does not extend to letting children determine what they put into their mouths every day. So, if you’d like your child to drink more water, my advice is not to offer alternative or even have them in the home.
This may seem like a hard line and might get some resistance for a day or three, but the long terms benefits in terms of health are usually worthwhile. This approach if applied more globally generally helps meal times go much more smoothly, once a child realises he or she cannot influence the food they are given through refusal, tears or tantrums.
References:
1. Lanou AJ, et al. Calcium, dairy products, and bone health in children and young adults: a reevaluation of the evidence. Pediatrics. 2005;115(3):736-43
2. Winzenberg T, et al. Effects of calcium supplementation on bone density in healthy children: meta-analysis of randomised controlled trials. BMJ 2006;333:775-778