...on animal behavior

"I'm afraid of cats because it's difficult to tell their emotion."

... skin pigmentation

"My sister is so black because my mom drank a lot of tea while she was pregnant."

...on the Weather

"If you let the rain fall on your head, you will become bald."

-I suppose this could be related to the air pollution in many places in Taiwan..

...on menstruation

"We can not drink cold drinks when that thing comes."
"That thing" refers to her period, as known as Little Auntie (小阿姨). She also refrains from drinking cold drinks during the "cold months" of October through May.

"This time my period lasting longer because I ate Yaodun Paigu."
Yaodun Paigu (藥燉排骨) is an herbal stew of pork ribs and Chinese medicine.

...on ghosts

"We can not swimming during Ghost Month because some ghost will in water and pull you down. This happen mostly in rivers, swimming pools are still safe."

FYI: Ghost month is the seventh luanr month according to the Chinese calendar, typically in August.

My Taiwanese Girlfriend on Astrology

"If you point at the moon, your ear will get cut."

My Taiwanese Girlfriend on Health

"If you go outside with wet hair, you will have headaches when you get older."

"If your eyes have problems, you need to look more green things."
-But what if you're colorblind?

"I have asthma, so I can only eat ice cream on really hot days."