Have you given blood before?
I'd maybe do it on an add a meal week and ask the nurses what they think.
I would think you are more at risk of feeling lightheaded or fainting after so if you do it I would lie down for a long while after!
From reading i have done on VLCD's and in general (being a Biomedical Sciences Major...i know i'm a big geek) it's a BIG no no!
Your body just cant support a blood loss like that in ketosis, regardless of how many times you have donated before. You'll just have to wait till your skinny and back on a normal diet
which is much better than last time before I started when it was 140/80
(I know, a lot of women have a battery powered device at the side of their bed, mines a blood pressure machine ;-) )
I rang and asked them after I had been on it about 4 months and they said definitely NO - I am on a break for 6 months and then they will reinstate me back on the register, but if I am still doing TFR I have to ring them and let them know.
Bren xx