My grandfather used to say this - that “your taste buds change every 7 years”. He probably read it in an article somewhere back in the day, and although I am skeptical that it happens with such clockwork precision, there is no doubt in my mind that tastes change over the years. As a young adult I am a big fan of several foods that absolutely repulsed me as a kid - mustard, real mayo (instead of the Miracle Whip we grew up on), pickles, onions, etc. and no longer interested in most “candy”-like foods (this in particular seems to be a very common thing to grow out of).
As someone who worked in a restaurant I also noticed certain foods that were markedly popular with our older clientele: namely beets and rhubarb pie. I don’t think most of the younger and even middle aged guests knew what the hell rhubarb pie was, and stayed away from it, but the senior folk requested it regularly. Is this because beets and rhubarb were popular back in their days and they get nostalgic for it, or can it be chalked up to taste buds changing to like “old people stuff”?
The changing every seven years thing has been around since at least 1965. Here’s an example: Every Seven Years You Change
Apparently someone used the carbon 14 released in atomic tests to get better answers back in 2005:
I liked rhubarb as a kid, I like it now. Beets are a bit of an aquired taste.
Youngsters don’t eat rhubarb because their parents never introduced them to what is after all a very seasonal dish.
As I understand this, the 7 years represents a sort of average cell lifetime. It would be like saying of a country that its citizens change every 85 years.
It does not mean that the cells or citizens do this change in step with one another. There are always old ones disappearing and young ones appearing. I imagine incredulous people hearing the 7 year thing and wondering if that’s what happened last summer when they felt so funny for a couple days.
Also, different cells have very different lifetimes. Bone cells live a long slow life, whereas cells lining the small intestine are replaced quickly.
I saw something like this mentioned on the SDMB. Apparently your taste buds do change and it’s to do with growing up. A toddler has different tastes from a boy or a girl, who have different tastes from adults. One change when they’re able to wander from mother, another at puberty.
I can’t add to the discussion of science, but when I hear “every seven” anything, I can almost guarantee that it is folklore. (Not in the popular defintion of “untrue,” but in the technical sense of “whatever kernel of truth there is has been modified to conform to pre-existing cultural ideas via informal person-to-person transmission, and probably says more about the cultural psyche and our need to see ourselves as mutable and re-inventable than it does about biology.”)