wondering about high blood pressure?

My husband wants to start this cleanse when I am done and he is on meds for high blood pressure. He is also notorious for passing out when he doesnt eat enough. (low blood sugar?)he is 32 years old and quite lean. Dont know his actual weight. he is 6' tall and I think around 165-170 lb I am actually worried about him going on this cleanse. He is a gardener by trade and is quite active at his job. Does anyone see any red flag regarding him doing this cleanse? I feel aprehensive. does anyone here have high blood pressure or can relate? any help appreciated> Thanks!!! :>