@sherlock221b
The only research I’ve found says 140mL/day of juice. I didn’t want to do the juice, so I do about 2 teaspoons of beet powder 4 days a week. Seems to work for me pretty well. I’d start with 1 teaspoon to make sure it agrees with you. It’s not recommended that one not exceed 5 grams/day, which is about a half a tablespoon.

Be aware that it also helps to lower high blood pressure. So, if you naturally have low blood pressure or if you are on blood pressure medication, be sure to discuss it with your physician before taking it.