I think so, but I'm not 100% sure how it was producing cognitive effects. Most doctors don't seem to recommend K2 in addition to D3. Vitamin K would have helped to channel calcium into her bones and out of her soft-tissues. This would have helped significantly with her osteopenia and would have lowered her blood serum calcium levels.

The other thing that the article omits is that overweight people don't metabolize Vitamin D as effectively. It gets stored in fat. So if this subject was thin or in excellent shape, that would have been a factor in determining the proper dosage as well.