The most common time for hair loss is 3-4 months post-operatively and the explanation for it requires a quick lesson  on hair growth.  At any given moment, about 90% of the hair on your head is in a growth phase, growing at an average of about an inch per month.  The remaining 10% is in a resting, or dormant, phase in which it is not growing at all.  This hair is “pre-death” as it were and is hair that is likely to fall out after several months and not do much growing.  Surgery or any physically traumatic event (including serious illness, childbirth) will cause a greater percentage of the hair on your head to enter the resting phase, so 3-4 months later you suddenly start noticing all this hair falling out.  It will likely look a little thinner somewhat before then since there will be a greater percentage of your hair that is not in the growing phase.  This is usually a one time occurance, and after the hair falls out, the hair on your head usually returns to the normal 90%/10% split and appear normal to you.

The more concerning hair loss occurs because of malnutrition.  This can occur after large weight loss and is associated with a diet low in biotin, folate and protein.  Low levels of any of these nutrients in the diet can cause brittle hair that is not well anchored to the scalp and is easy to break or pull out, causing thinning of the overall appearance of the hair.  This loss can only be remedied by increasing protein intake (for Lap Band patients we suggest 40-60g protein per day, gastric bypass patients may require even more, and both sets of patients will need more if they are very physically active) and by taking vitamins.  Most Lap Band patients can prevent hair loss with 1-2 multivitamins per day, gastric bypass patients should consult their doctor since they may need 2 multivitamins and other more specific supplements each day depending on the type of operation they had.

So the bottom line is this: if you develop a sudden hair loss in the 3-4 month range after surgery, don’t worry too much.  Do, for the sake of completeness, make sure your protein and vitamin intake is adequate, but mostly we’re going to tell you not to worry too much as it’s likely to grow back normally without much outside intervention.  Hair loss at other times should prompt a discussion with your doctor about your diet.