Every one knows that spinach is good for you. However it isn’t as good for you as initially thought. Vincent McBurney over at ITToolbox.com wrote a post last year about the ‘spinach iron content controversy’ and its effect on people’s thinking about the health benefits of the leafy vegetable.
This qualifies as an IQ Trainwreck for many reasons, but the main one for me is that it means most of my childhood Saturday mornings were based on an IQ error… Popeye could never have gotten that strong eating spinach.
More importantly it teaches us some valuable lessons about the impact of poor information quality. Firstly, it can happen very easily (in this case a decimal point seems to have been in the wrong place due to a miscalculation).
Secondly, there may be a more complex ‘system’ at work that might affect the real business impact of the information (1000 orders pending might sound bad, but is it bad if they are in dispatch and the order will complete once the goods are delivered?).
Finally, the ‘conventional wisdom’ that pervades through an organisation can often be difficult to overcome, even when it is based on poor quality information and an incomplete understanding of the system (or information chain). Even today there are many people who think that spinach is a good source of iron in the diet, even though the system is complex (only 2%-5% of iron in spinach is absorbed) and the iron content is lower than many people think (90% lower to be precise).
This was a good data quality mistake since it inspired the Popeye cartoon and made people eat more spinach – which has a lot of other good qualities other than iron.
The good news is that you can get iron from Guinness. If for example you were to become vegetarian you would just substitute a lamb chop at dinner for 7 pints of Guinness and you get the same amount of iron! Even better news, six pints of Guinness has the same iron as a bowl of porridge.