It often seems to me that one thing we all believe we are expert in is the field of nutrition. I’ve noticed that chefs and food writers are prone to make statements on nutrition despite being more knowledgeable about the aesthetics of food than the nutritional benefits. I’ve also noticed that members of the public often ask chefs and food writers questions on nutrition and the health benefits of food.
In the Guardian’s Weekend section on 22nd August, Matthew Fort was asked by a reader (who had “read about the many health benefits of apple cider vinegar”) whether ordinary cider would have the same health-giving properties. In the following edition of the magazine, a letter appeared criticising Matthew Fort for writing that yeast “feeds on the alcohol, converting sugars into acetic acid” and pointing out that yeast feeds on sugars to produce alcohol which, if exposed to air, will oxidise to produce acetic acid. This letter reminded me that I had myself taken issue with elements of Fort’s reply.
Fort wrote that “I have been told that serious cider drinkers in the Forest of Dean routinely live well into their 80s, active in all their parts”. This is an anecdote, and possibly an unhelpful one at that – it reminds me of the oft-quoted argument about smoking increasing the risks of lung cancer and heart disease (“my gran smoked 80-a-day and she lived to be 90 years old…”). Whether being a “serious cider drinker” is beneficial or harmful or whether is can aid longevity or make an early grave more likely is not a question that should be settled by something as notoriously unreliable as anecdote.
Fort went on to use science to support his argument in favour of drinking cider. Apparently, “scientists at Brewing Research International have confirmed that cider contains high levels of antioxidants”. They haven’t confirmed that cider is beneficial – merely that it contains substances that are thought to be beneficial. Arguing for the health benefits of an alcoholic drink on the basis that it contains one or more other ingredients that may be beneficial is somewhat irrational. There is a history of journalists using research into a component of foodstuffs to make claims for a specific food or drink that is not supported by evidence that relates to that foodstuff: I’ve written about it before, as has Ben Goldacre.
I can understand why someone would want to consult Matthew Fort as an expert if their question involves the best way to make crème caramel, but questions about health-giving properties do not come into the category of “culinary dilemmas”. There are people who could truly be described as experts in nutrition – they are generally referred to as “dietitians” or “academics”. Registered dietitians are “uniquely qualified to translate scientific information about food into practical dietary advice” (link). There are academic researchers, meanwhile, who publish articles on nutrition in respectable journals that are indexed on Pubmed. Food critics, chefs, and self-appointed nutritionists are not experts in nutrition.