In the Netherlands we have a snack called Studentenhaver, which roughly translates as Student oats. This is a mix of walnuts, cashew nuts, Brazil nuts, almonds, hazelnuts, raisins and sometimes other dried fruits. This mix is supposed to enhance intelligence, hence the name.
We supplement our food with lots of nuts, not because it would increase our intelligence, but because of all the benefits nuts contain. We rarely eat meat, which is another reason to eat nuts. Although the main reason is that they are delicious. We love nuts.