How to prevent Thai mosquitoes

This is interesting. Isaan people (and Thais) do not get bitten by nearly as many mosquitoes as farang(Westerners) do. For that matter, I get bitten very little as well. I tried to look for some internet information about this phenomenon, but I have found nothing the least bit scholarly, so I am going to put forth a hypothesis: Eating spicy Isaan food prevents mosquito bites. Here are the facts:

• Most farang get bitten a lot by mosquitoes. 
• Isaan people get bitten very little.
• I get bitten very little.
• When I stop eating a lot of spicy/Isaan food I start getting bitten a lot.

I wish there was a way to actually test this scientifically, but I am certainly no expert on the scientific method. I also wish I could find scholarly material on the subject.