Springtime. The season for sneezin'. But why, just because plants want to have a good time and reproduce, do we have to suffer through the sneezes, the watery red eyes, and the runny noses? Don't blame the flowers for all your super-attractive sniffles, says the latest episode of It's Okay To Be Smart, because their pollen is actually too heavy to get airborne and into our sinuses anyway. In reality, they get bees to assist them with the, erm, 'sexy stuff', so there's no reason for them to sow their seed into the air.

Trees and grasses, on the other hand, well, sometimes they just get a little too enthusiastic about how much genetic material they need to put on the wind to successfully reproduce. And at the same time, our immune system, which is usually the good guy, goes completely haywire. It wages war against things which are actually harmless, says Joe Hanson in the video above, including dust, pollen, and microscopic pet particles.

One particular antibody produced by our immune system, called IgE, seems to be the main culprit for our allergic reactions. I'll let Joe explain why above, because he's so good at that, but let's just say it's something about vacuum cleaners, a Mr T cell, and an old school telephone. 

Strangely enough, allergies aren't just common in developed nations, they're actually increasingly on the rise around the world, particularly when it comes to food. The trend appears to be that as a nation gets richer, its population becomes more allergic, and the scientific reason behind it is fascinating. Watch It's Okay To Be Smart above to find out.

Source: It's Okay To Be Smart