I could hardly walk for about 2 years before I started NB. It took about six months but now I can go to the grocery store/shopping, or for a leisure walk without much difficulty. Granted I didn't follow the NB EXACTLY as recommended. For example, I took lower dosages of mag/calcium than recommended and I only took copper supplements a few times before I realized that I couldn't tolerate them. Also I have the MHTFR mutation so I had to take a different form of vitamin b than what NB offered for methylation purposes. But generally NB gives you a good report to start with and then later you can make changes as necessary.