Hair loss is a common concern after bariatric surgery. About 40% of patients experince some hair loss however, complete hair loss does not occur. Hair loss usually start about three to five months after surgery and tend to correct itself as weight starts to stabilize at 12-18 months after surgery.
What causes the hair loss after weight-loss surgery?
Hair loss after weight loss surgery is a type of Telogen Effluvium (TE). But before we discuss TE, it helps to know first the normal phases of hair development. There are three phases:
- Anagen or The Growth Phase
Approximately 85% of the hairs are in this phase at any period of time. This phase lasts for about 2 to 6 years.
- Catagen or the Transitional Phase
The hair follicle's outer root sheath shrinks and stops developing hair. This phase lasts for 2 to 3 weeks.
- Telogen or The Resting Phase
This is where hair stops growing at all for about 100 days (3 months). Approximately 5% to 15% of hairs are in the telogen phase at any one time. At the end of telogen, hair is shed and the follicle begins a new anagen phase and another hair emerges.
Telogen Effluvium happens when a specific type of stress causes premature termination of anagen phase thus shifting a much greater percentage of hairs into the telogen phase. So after about 3 months the hair starts to fall at a much greater rate than usual. Stressors known to cause teleogen effluvium include high fever, child birth, bariatric surgery, severe blood loss, low protein intake and physical trauma.
Patients having chemotherapy or irradiation therapy, on the other hand, lose hair in a different way called Anagen Effluvium. Here, there is a sudden termination of the anagen (growth) phase leading to hair loss. This is very different from teleogen effluvium.
How soon hair loss occus after bariatric surgery?
With the stress of obesity surgery and the onset of rapid weight loss hair starts to fall usually at 3 months after the surgery. This continues until all the hair in the telogen phase has fallen and new hair start to grow. In the absence of any nutritional deficiency hair loss will not continue more than six months. Hair loss is more noticeable after gastric bypass than after sleeve or gastric banding as weight loss is more rapid after gastric bypass.
When one should suspect that a nutritional cause is behind hair loss?
If any of the following occurs, a nutritional cause should be expected:
- Hair loss continues more than one year after surgery
- Hair loss is not starting until six months after surgery
- Blood tests show low iron, zinc or protein
- Patient is not taking enough protein and multivitamin supplements