The diet one follows has become a sort of religion: “a pursuit or interest to which someone ascribes supreme importance”, “something one believes in and follows devotedly”, “the body of persons adhering to a particular set of beliefs and practices”. There is increasing pressure to define the dietary principles one believes in and then to have some evidence to back it up. Social media is abuzz with pictures of food captioned with hashtags that define the diet box into which that plate, bowl, or take-away cup falls. And as you scroll through your Instagram feed or read sensationalist headlines in newspapers or see the new raw-low-carb-vegan-health-conscious-soul-food café open on the corner, you start wondering: is there a single right diet for optimal health and, if so, who the heck do I actually believe? Perhaps Noakes’ epiphany was heaven-sent, or maybe you should still believe good old doctors and their low-fat advice to prevent heart disease… perhaps raw vegans are onto something with their raw desserts and cashew nut “cheese”, but then again that Sunday braai and Karoo boerewors would be quite a sacrifice! “If only there were a way to find out what truly works for me” you ask? Ah, but wait, I may just have your answer!
Blanket nutritional recommendations have plagued public health for years: the idea that there is a “one size fits all” approach, which is based on epidemiological studies. Furthermore, these guidelines do not always have their foundations in sound science and are propagated to suit the pockets of big enterprise. For example, the original food pyramid was actually changed from the healthier one originally proposed by the US Department of Agriculture’s (USDA) dietary guidance director, Luise Light, in order to suit the agricultural secretary and head of the USDA, John Block, who had his fingers in other pies! Guidelines are forever changing, new diet fads are published by so-called experts, and health shops and restaurants capitalize (literally!) on the current hype. Research hardly helps to clear the confusion either – just as one study shows an outright winner, another is published showing mixed results! Well, perhaps that’s where the key to this saga lies: we are individuals with our own genetic make-up, so is it not understandable then that the way we respond to food and medicine is going to be different? Personalized medicine – that is the future.
But the future of medicine may not be so futuristic anymore – perhaps less so in this country, but overseas there are companies popping up offering DNA testing and analysis, simply by ordering a kit and providing a saliva sample, following which one is provided with a report detailing risk for a wide range of inherited conditions and genetic disorders. Nutrigenomics describes the role of nutrition and its effect on gene expression, whereas nutrigenetics refers to the role of genetic variation in the response to nutrients. These two concepts are the scientific basis behind why humans have different preferences, requirements, and responses to food. So in the endless debate between low-carb and low-fat, it may just be your variant of the ApoE gene that determines the right approach for you in terms of your risk for cardiovascular disease and Alzheimer’s. Another gene (PPARg) will guide you as to whether fish oil will have a positive influence on blood lipid lowering; yet another (CYP1A2) will decide whether you load up the filter coffee machine for another cuppa or load it on eBay to decrease your risk for heart attacks due to slow caffeine metabolism; and more still, can tell you whether you should follow in the footsteps of sprinter Usain Bolt or marathon runner Eliud Kipchoge.
So where does this leave us? On the cusp of personalised medicine but currently with inadequate access to tools to analyse the best fit. Practically speaking, this means that endless debates as to what is “the best diet” are futile – as the saying goes “one man’s meat is another man’s poison”. I think we can all agree on one thing and that is that processed foods have no place in our diet. As far as possible, eat whole foods that come from the earth, free-range grass-fed animals, and fermented foods to support gut microbial diversity. If it comes in a box, put it back on its man-made shelf. If it’s sold at a market, support the grower or farmer. If there’s an ingredient you cannot pronounce with a letter and numbers in brackets, it’s probably not a food. Be mindful of what you put in your mouth – your body and health deserve that respect.