High folate normal B12

My sister has a high blood folate level but her Vitamin B12 is normal. Everything I read is about pregnancy. She is 62 years old and complains only of joint pain, for which she is being tested by other blood tests.  I am a clinical microbiologist and am familiar with many blood tests but mostly learned about LOW folate/B12 levels.

Does high folate in and of itself a sign of something?

[Renee Radenberg]

She may have eaten food high in folate before the test which may have increased the levels.