By Kate Prengaman
Sometimes, it feels like there is too much advice for healthy eating. Health food fads like gluten free, or low sugar, or whole grain or eating only local, seasonal food have all become pretty popular recently. Fads like low fat and no carbohydrate diets seem to be fading out in the enthusiasm for the new trends. I recently discovered Google’s ngrams viewer, a tool that you can use to view the frequency of word use in a large subset of all of the books published every year. Search for a specific word that represents a cultural idea, like “low fat diet” and you can use the graph of it’s frequency to know when it became a popular. I wrote a larger post about the science of the ngram tool, you can read it here.
For this graph, I searched for the frequency of currently popular health food terminology, inlcuding “local food” in dark blue, “low fat” in red, “organic food” in green, “GMO” in light blue, and “trans fat” in yellow. The graph runs from 1800 to 2008. The high point on the chart is the term “GMO” in about 2003; about 0.000028% of all the words published that year were “GMO.” The trends that I think are particularly interesting in this graph is that “organic food” has been written about, consistently, since the 1840s, but then began a spike around 1990. Local food and low fat food have been increasing in published popularity, steadily, at a surprisingly similar rate, since 1900. The next graph, below, shows the same words, just zoomed in on the past 50 years.
Here, you can see that trans fats arrive on the scene about 1995. The term GMO begins to be used, at a very low frequency, since the 1970s, but begins to spike in popularity in the 1990s. The terms local food and low fat are used at pretty consistent rates throughout the past 50 years, rising slightly in the past 2 decades. It surprised me to see that local food has been a popularly used term for almost 100 years, as long as low fat. It seems like local food is a new, hip idea in our era of eco-consciousness, but actually, people have been writing about it for awhile.
However, on the scheme of things, all of this particular food terms are very rare. If I add the word “diet” to the graph, the variation between the terms viewed above flat-lines, all smushed together in the practically zero section at the bottom of the graph:
The last graph I made fits on on a story I’ve been researching for a while, the history of vitamins, the scientists who discovered them, the advertisements that popularized them, etc… So, I decided to graph when “vitamins” became a household name, through frequency of publication, and which vitamins were written about the most:
The first vitamin, A, was discovered in teens at the University of Wisconsin. The blue line represents the term “vitamins”, which has been decreasing since it’s peak in the 1940s. Vitamin A, the first one discovered, stays the most common until the 1970s, when Vitamin D takes the lead, in light blue. Vitamin K, in pink, as you can see from the graph, is the last discovered, in the late 1930s. I was expecting to see Vitamin D pass A back in the late 1930s, because in advertising, D was most frequently referenced, because it could be artificially produced and added to foods. But, in books, A apparently held on to the lead. I’ll be writing a lot more about the history of vitamins in a few upcoming stories, but I wanted to include this graph in this post.
The Google ngram viewer can be found here. Check it out and trace the patterns in whatever words you find interesting. If you discover any surprising trends, please let me know in the comments below. Thanks!