Hi.
One of the recipes include egg yolk. egg yolk has a lot of vitamins itself, that's why it is enough to use that recipe once a week. I guess twice a week would do no harm. It is just that the marginal benefit of doing it the second time in a week may not be as much as the first.
The other one includes black cumin seeds, olive oil and NO egg yolk. Hence you can use it twice a week.