Does the cb-1 weight gainer pills actually work to help gain weight?

Not by itself, no.: CB-! "weight gainer" will not help w/ weight gain. Get a check up to make sure there's no medical cause of or consequence to your low body weight. If you're otherwise healthy, start a regimen of weight training & adequate calorie intake (esp. protein & healthy fats). Taking a daily multi-vit. w/iron is fine, but don't waste your money on unproven supplements like CB-1. Best wishes! Dr. Anne.