I would go for the blood test for an elderly person for MMA. Kidney functions are not so great in 70+ yr old patients.
I don't know how much higher the test will be if you stop supplements now. There are no studies on this situation.
But I'd expect some difference from NO supplements ever.
When people don't stop their supplements, very high readings can result. Perhaps those of your mother's won't be so high, but they won't say much about where she started from.
If she is testing out very low, then I'd believe that reading. But closer to "normal" 400pg/ml may not say much.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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