I had some hair loss during pregnancy with my 2nd, and it didn't grow back, that was until I stopped using commercial shampoos. I make my own soap, so I custom formulated a soap to clean and condition my hair. My once sparse patches are filled in now (mostly at the top of my head) finally.
However, before I go claiming its the shampoo bar, I beleive that its because I'm no longer using a detergent, SLSA/SLS heavy liquid shampoo that was stripping the natural oils from my hair and clogging pores. I also added peppermint to it, which stimulates hair growth, provided the folicle isn't dead.
Rough start due to major carb WD.
MWF: 1 hour run/walk, 1.5 hours in the gym - upper/lower and core
Sat/Sun=Yard/house work, chasing kids, playing
Family walk every night instead of everyone vegging in front of the TV
Personal trainer to build muscle mass & to help meet goals