With the Royal Society of Chemistry’s Science Communication Competition currently underway in Chemistry World magazine, now seems like as good a time as ever to share my 2013 entry. Any feed back is gratefully received, as I’m currently working on my 2014 entry!
Vitamin C: From Scurvy to Synthesis
Between the fifteenth and seventeenth centuries, scurvy killed more sailors than all other diseases combined. The symptoms include fatigue, bleeding of the joints, and the characteristic tooth loss. Of course, today we know that scurvy is simply Vitamin C deficiency, which can easily be avoided by drinking a glass of orange juice every now and again. However, this hasn’t always been the case.
In 1747, a Scottish physician named James Lind carried out some of the first clinical trials to support his theory that consumption of citrus fruits could prevent scurvy. In his role as military surgeon aboard the HMS Salisbury, he trialled the treatment on two scorbutic sailors; although he soon ran out of fruit, one of the soldiers was cured and ready to return to duty, and the other showed significant improvement. This evidence, however, was largely ignored during Lind’s lifetime. Having heard of Lind’s experiment, explorer James Cook reputedly gave citrus juice to his crew to prevent scurvy. This could have been the endorsement the discovery needed, had it not been for Cook’s political ties which meant that publicly he was obliged to promote “Wort of Malt”, a remedy which contained no vitamin C and hence could not have been effective. Finally, in 1795, citrus juice was made mandatory for all sailors in the Royal Navy. This was largely due to Sir Gilbert Blane, Physician to the Fleet and advocate for Lind’s research. Despite the politics and well established theory within the medical community at the time, the openness with which Lind treated his work meant that it could finally be used to help fight scurvy, albeit after his death.
Fast forward to Switzerland, 1933. By this point it was known that vitamin C could be found in citrus fruits, and that it was necessary for human health. This was due to the research of Hungarian Physiologist, Albert Szent-Györgyi, who after discovering vitamin C went on to conduct experiments demonstrating its anti-scurvy properties in guinea pigs. A group of Swiss chemists headed by Tadeus Reichstein was able to synthesise D-ascorbic acid, a rotamer of vitamin C, from d-xylosone. Enter Norman Haworth and Edmund Hirst, a research partnership based in Birmingham. Later that same year, they were able to build upon the work of the Swiss chemists and successfully synthesise L-ascorbic acid, or vitamin C. The name “ascorbic acid” refers to the properties discovered by Szent-Györgyi; “ascorbic” means “anti-scurvy”. This triumph led to a Nobel Prize for Haworth and Swiss Chemist Paul Karrer in 1937, and readily available vitamin C for medical purposes.
This advance has, however, yet to be fully embraced. In recent years public mistrust of “chemicals” in food, drink and seemingly all other areas of life has risen alarmingly. There is a backlash against supposedly “synthetic vitamins”, such as Haworth’s vitamin C, and a number of retailers have sprung up selling products labelled “raw vitamins”. This trade exploits the public misconception that there is any chemical difference between a compound isolated from a natural source and one synthesised in a lab. One such retailer offers the advice to “avoid supplements that use words ending in –acid, -ide, and sometimes –ate” (the same retailer’s products contain “plant based ionic trace minerals”, which presumably would by any other name be wholly unacceptable). This is a relatively new development upon one of the media’s favourite scapegoats, additives in food. When the general public, lacking any specialist knowledge, are presented with a sensationalist view of the topic, they have no reason not to accept it.
Work is thankfully being done to remedy this. A charity called Sense About Science makes it their business to correct such misconceptions by creating an open dialogue between the public and the scientific community. They have put together a large online resource which tackles myths about food additives, along with numerous others. By working with experts in the relevant fields, they promote engagement and openness between scientists and the public, and publish numerous resources to help anyone who is interested to interpret the data themselves. The RSC’s own “Global Experiment” also aims to increase engagement – this year using social media to open the dialogue up even further. The experiment measured the quantity of vitamin C in various fruits, a piece of kitchen science which echoes Lind’s own experiment over 250 years ago. By acquainting young minds with the scientific process, we can build a relationship of openness and involvement between science and the public that can continue to grow for years to come.