I have heard this too. If I juice slightly too much beets in the morning I find that I can't eat anything else for around 8 hours or so without feeling like I need to throw up (purge) from the fullness it gives me. Right now I can't even juice 1/2 a small beet without having that sensation. So I'm juicing my beets every other day and a 1/4 of a beet at a time. Normally one medium size beet gives me about a 1/4 cup of beet juice. So even half a beet is around 1/8 of a cup of actual juice. So for me, I'm still stuck at 1/16th of a cup of actual juice (about a half ounce) at a time. Maybe I need to add more lettuce juice or carrot to the mixture.