[basisword]

Curious on what basis you're making this recommendation. It's the kind of thing I would normally read and recall at a later stage as good info, but my doctor prescribed me 20k IU a week recently for a period of a couple of months.

[panax]

If your doctor prescribed you that then that is fine you should follow your doctor's advice. They might have specific reasons for the high dose.

I was once prescribed a 50k dose by my doctor but had very noticeable negative effects and I know that was far too high for me.

The recommended daily allowance is like 400 and that should cover the needs of most people. If you are deficient then you probably want quite a bit more than that until you get back to normal. The safe upper limit is 4000 /day so I would probably try to stick to doses below that. If you take 2000 per day that should be well within the safe range, and even if you take 2000 on as few as 2 days/week that probably covers your needs. Some individuals might have trouble absorbing it and might need higher doses though.

[xk_id]

> if you take 2000 on as few as 2 days/week that probably covers your needs

Well the linked study actually found that taking the supplement once a week or month didn’t provide the benefits of dosing daily. Also the daily dose which was effective was up to 4000.

[KSS42]

The only way to tell is to do a blood test. It took me taking 10k IU a day to get to the mid point recommended range. On the plus side, daily 10K IU is covered by my drug plan. I get my levels tested every 3 months.