I just saw my dermatologist today for hair loss and she confirmed that rapid weight loss will cause hair loss. I have lost 40 lbs in 6 months and she said that is rapid enough for hair loss. She suggested biotin and said I can get it from a health food store and rogaine.

No hair loss from Medifast here, but did lose my hair some from the massively bad diet I was on of cheeseburgers, pizza, processed crap.

Ugh, down 60 lbs in 5 months and I'm in the thick of hair loss. The bad news is, it's coming out big time. The good news is, it's not permanent.

Here's a description of the phenomenon:

Telogen Effluvium

Telogen effluvium is a phenomenon that occurs after pregnancy, major surgery, drastic weight loss, or extreme stress, in which you shed large amounts of hair every day, usually when shampooing, styling, or brushing. It can also be a side effect of certain medications, such as antidepressants, beta-blockers, and nonsteroidal anti-inflammatory drugs. During telogen effluvium, hair shifts faster than normal from its growing phase into the "resting" phase before moving quickly into the shedding, or telogen, phase.

The symptoms: Women with telogen effluvium typically notice hair loss 6 weeks to 3 months after a stressful event. At its peak, you may lose handfuls of hair.

The tests: There are no tests for telogen effluvium, but your doctor may ask you about recent life events and look for small "club- shaped" bulbs on the fallen hair's roots. The bulbs mean the hair has gone through a complete cycle of growth, suggesting that the cycle may have sped up due to stress.

What you can do: In some cases, such as pregnancy or major surgery, you may have to bide your time until the hair loss slows. If medication is the culprit, talk to your doctor about lowering your dosage or switching drugs. If it's stress-related, do your best to reduce anxiety.

I was shedding more in the first month but it tapered off. this is why I always recommend people take the medifast supplements...biotin omega three and the digestive health. I lost hair doing all of my diets including weight watchers... it's from losing weight rapidly...(more than a pound a week) The bigger a person is the higher the calorie deficit will be and the faster they will lose weight...thus causing some hair loss...it grows back