I recently saw a holistic health practitioner who recommended that I take bladderwrack and thyroid calming liquid extracts for generalized anxiety issues that I've dealt with for some time. The practitioner assessed that I my thyroid is producing chemicals out of balance and that much of my anxiety is the result of being in an aerobic instead of anaerobic metabolic mode throughout the day (at least I think that's what he said; I hope that makes sense). He recommended that I take bladderwrack and thyroid calming liquid extracts with water three times a day.

I'm a 26 year old male who is currently a healthy weight with no need to either gain or lose weight. If I start the bladderwrack and thyroid calming regimen can I expect to gain weight as result of a lower metabolic rate throughout the day? I'm concerned that taking these two herbal extracts will cause me to gain weight.