The Sunday Herald yesterday ran about half a good article on the way in which diet/supplementation can be used to modify the way in which our genes are expressed. The second half of the article, however, draws on Holford’s ‘knowledge’ of the subject: he argues that “Manipulating people’s genes can help you fine tune your diet but I am deeply suspicious about what we are going to be able to do with any level of safety”.
This does sound scary, like scientists are planning on genetically engineering adult humans in order to improve their diet – insert a special spinach-loving gene, for example. This would be scary, but it’s also (at least in the foreseeable future) total rubbish – no-one is going to modify the genes of adults just in order to improve their diet. This type of gene therapy is currently experimental, difficult, dangerous and very expensive – while it may be useful for treating some diseases, it’s not going to be used to make people eat better. Put bluntly, it’s much easier, cheaper and safer to persuade or bully people into eating sensibly than to try to modify their DNA.
What the (sensible first half of) the Sunday Herald article was discussing was the use of diet/supplementation to modify the ways in which particular genes are expressed. For example, while certain genes are risk factors for neural tube defects (such as spinal bifida) in children, one can often prevent these genes from being expressed in this way through giving the mother folic acid supplements.
So, we’re not talking about scary, evil scientists looking to carry out dangerous experiments on adult humans – genetically engineering great armies of spinach-loving supermen. Instead, a greater knowledge the human genome will allow us to modify our diets – based on our own genetics – in order to avoid certain undesirable expressions of these genes: for example, supplementation with folic acid to reduce the risk of birth defects. Safe, effective nutritional therapy – assuming Patrick Holford actually understands what he’s talking about, it’s hard to see why he would oppose this.