Hair loss and thinning. It’s one of the most common worries after weight-loss surgery with the least understanding of the causes.

Not everyone will lose hair after weight loss surgery, but many folks do.There are a number of reasons for hair loss after weight loss surgery and it can’t always be prevented. Rest assured, though, hair loss is usually only temporary, most people do not go bald, and it usually grows back as thick and lovely as ever!

Keep in mind, too, that people can experience hair loss for many reasons unrelated to weight loss surgery, including thyroid disorders, skin disorders, and hormonal problems. Talk to your doctor if you’re losing a lot of hair and aren’t sure why.But here are some reasons why weight-loss surgery patients can experience hair loss and thinning.

Telogen Effluvium

Telogen effluvium is a technical-sounding name for a change in the growth cycles of your hair. According to Web MD, most of the time about 90% of your hair is in a growing, or anagen, phase. The other 10% is in a resting, or telogen, phase. After the hair rests for a few months, it falls out. It’s normal to shed some hair every day. Sometimes, though, something causes more hair than normal to go into the resting phase, such as surgery requiring general anesthesia. After the hair rests for a few months, it falls out, causing more hair loss than normal. Telogen effluvium can occur after any surgery, not just weight loss surgery. It usually lasts for less than six months.

Protein

Not getting enough protein can lead to hair loss, but it’s important to understand that falling short of your protein goal for a few days is not going to make your hair fall out. Hair loss can occur if you get too little protein on an ongoing basis, however. The American Society for Metabolic and Bariatric Surgery suggests consuming 1.1 grams of protein per kilogram of ideal body weight for weight loss surgery patients. Some people may need more, though, and some less. Your doctor can order blood tests to see if you’re getting enough protein for your body.

Vitamins and Minerals

Numerous vitamin and mineral deficiencies can cause hair loss and nutritional deficiencies are more common after weight loss surgery. That’s because weight loss surgery patients eat smaller amounts of food than “normal” folks, plus RNY and DS folks malabsorb nutrients. Low levels of many vitamins and minerals can cause hair loss, including low levels of iron, zinc, vitamin A, and some of the B vitamins. If you think nutritional deficiencies might be contributing to hair loss after weight loss surgery, ask your doctor to order some labs to see what vitamins or minerals you might need to add to your daily regimen.

Biotin

Biotin is one of the B vitamins. According to the Linus Pauling Institute at Oregon State University, biotin deficiency causes hair loss, a scaly red rash on the face, depression, fatigue, hallucinations, and numbness and tingling in the hands and feet. Biotin deficiency is very rare, however. As long as you eat a reasonably healthful diet and take a good multivitamin, it’s unlikely you’ll be low on biotin.

Many people take biotin supplements after weight loss surgery, hoping that will prevent hair loss, but the Linus Pauling Institute website states there is no evidence at all that taking extra biotin will prevent hair loss or make hair grow back faster. If you have a biotin deficiency, you should take a biotin supplement. Otherwise, taking one probably will not help your hair.