Parasites, low body temperature, and food allergies

I’m reading on the net and found an interesting article on Positive Health in which a correlation between low body temperature and food allergies is presented.

I have low body temperature, 96.8 average untreated. On my thyroid medicine, it has inched up to 97.5.

But this guy is saying that maybe low body temp keeps the parasites in your body alive and you could kill them off, and get rid of your food allergies, if your body temp were just a bit higher.

How do you warm up your core body temp?