They're not entirely based on lies though. At these temperatures, you're not going to catch a cold from sleeping nude, but damp and cold conditions do actually increase your chances of a common cold, but in this case, it really won't.
I'm honestly far too hot at night, and I really just wish I could sleep with ice packs on my face. I'd have the room entirely open, but the Dogs & Cat don't get along
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Exactly, but as has been said, if they're talking about these temperatures, they're no-where near cold enough to cause an issue, and it is even less likely someone has given you the virus at this time of year.