No there is no danger with high dose oral B12. Only if you have a rare blood disease called polycythemia vera which is too many red blood cells, should you avoid high dose.
A 1000mcg dose of methylcobalamin will only lead to 13mcg absorption. All the rest is left in the stool.
You can take the 5000mcg for 3 months, as that will bring you up in the brain and spinal fluid faster than a smaller dose. Once you have been using for 3 months you can drop down to 1000 or 2000 mcg etc if you want. That is enough to maintain you. The B12 only gets into the spinal fluid and brain by a concentration gradient. The higher the blood value the more gets into the brain. Being low or having an injury requiring repair, does better with higher levels.
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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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