Is it safe to take collagen supplements while breastfeeding? My joints keep "clicking" and my friend who's a physical therapist recommended taking collagen.

Based on what I’ve read so far, most collagen supplement would indicate to check with doctor for breastfeeding mothers before consuming the supplement. Also, there are very few studies on the effectiveness of collagen on joint issues. Perhaps you could consider asking your friend for an exercise guide (such as doing squats) on strengthening the leg muscles so that you would place less pressure on your knees? Also, observe good posture when squatting and lifting heavy object from the ground. When squatting, bend from the knees and keep your back straight. Lift the object by straightening your knees.