Jan 4, 2017
This is an article which I wrote somewhen in 2015 (or 2014, I don’t really remember), but was never sure about how publish-worthy it is. I decided it’s better to publish it now than to leave it lying around.
Valerie reacts allergic to nuts since her early childhood. By chance we found out that she can eat macadamia nuts a couple of months ago. There were other inconsistencies as well: one time she ate a cake and afterwards was told that it contained Milka chocolate — which contains a large amount of hazelnut paste. She didn’t get an allergic reaction from the cake though. But on all other occasions there was a strong allergic reaction when she ate something containing nuts — even if she was unaware of nuts being in the food. This goes so far that when buying ice cream from an ice cream stand, she gets an allergic reaction if the spoon used to take out the ice was in contact with a nutty ice cream.
Then one day a friend told us that she thought she was allergic against peanuts for a very long time, but then found out that she isn’t at all. The background was that her dad reacts allergic on peanuts and when she had an allergic reaction as a child he derived that she had to be too. For years she shared that assumption, until she ate some food unaware of the peanuts inside without any problems whatsoever.
So the small inconsistencies with Valerie’s nut allergy spawned an idea inspired by our university experiences in study methodology and experiment design: why not execute a double-blind self experiment in order to determine if she is really allergic against nuts?
We thus decided to do this. With Leo’s help we baked two types of cookies: one type with chopped almonds and one type with chopped hazelnuts. The idea was for Valerie to eat them and to determine if she had an allergic reaction. We used chopped almonds in order to make the two types of cookies indistinguishable.
In order to further mask the color and taste of the two types we put a large amount of chocolate and cacao into the dough. Right before we baked the cookies we splitted the dough in two parts and added the hazelnuts/almonds. Thus we could exclude a previous nut contamination of the “control group” dough.
A trusted third party (Leo) chose three pieces of each type from the resulting cookies whilst we were in another room. Leo then wrapped each cookie in aluminium foil and wrote a number on the foil. He noted the classification of number+cookie in a sealed letter and put the cookies in a box.
For the next three days we repeated the testing procedure each morning and evening: Valerie would receive a blindfold, I would then pick a random wrapped cookie from the box and feed some pieces to her. Whenever she started to experience an allergic reaction we stopped (and I ate the rest of the cookie). We didn’t want to risk a heavy allergic reaction.
We noted all her guesses and after the three days opened the envelope and checked against the true numbers. As it turns out she really reacts allergic to nuts :/. She guessed all of the probes right, except one were she wasn’t entirely sure, since she had to try it on short notice, stressfully, in between the door after having overslept and being too late for an appointment.