METAIRIE, La. — You've seen the ads: Regrow your thinning hair by just shining lights on your head.

So, do they work? We got answers from a hair restoration doctor, and found out there are still some unanswered questions. 

Before you spend hundreds or even thousands of dollars on laser combs, headbands or baseball caps, hair restoration surgeon Dr. Nicole Rogers says first check with a doctor to see what kind of hair loss you have.

"The devices have been most consistently for male or female pattern hair loss.  And in those cases, patients already have some of those little soft vellus which will respond, hopefully, to the light," said Rogers, a dermatologist at Hair Restoration of the South in Metairie.

So, if you're one of the 50 percent of women or men with inherited pattern baldness, the scientific data show lights could work for you.

If you have scaring from chemical processes or traction hair loss (from tight or sewn-in styles), you may need more advanced treatment from a doctor. The same goes for people with pattern baldness where none of the little, fine hairs are left.

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The good news about lights is they are safe, so you don't need a prescription and they can be used privately at home. 

Rogers says there are some studies to back up their effectiveness.

"The data seems fairly consistent in that whatever device you're using, there probably is some increase in hair growth as a result of it. The problem is we just don't have good head to head studies showing which device is the best," Rogers said.

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When using these various devices, Rogers recommended to keep the wavelength at 595-695 nanometers, and to make a commitment to use it at least three times a week.

But here's what we don't know: Will cap lights get through the thicker hair on your head to reach your scalp on thin areas? 

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With a comb, you can just push it close to your skin. Still, will the lights penetrate darker, more pigmented skin, as well? 

The answer: We just don't know yet.

"It won't hurt to use these devices and it may help a little bit," Rogers added.

And if these devices are not enough help, there are many approved, tried-and-true medications, supplements and procedures that do work.

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See the full list of approved supplements, medications and procedures:

  • Hair transplant surgery
  • Minoxidil products: Saves and regrows hair.  
  • Propecia Rx for men is now off-patent so the cost has gone down. Women can use it but must not get pregnant while on it.  
  • Spironolactone diuretic pill Rx
  • Nutrafol supplements
  • Viviscal Pro supplements
  • Platelet rich plasma, injection of your plasma spun out of your small blood sample and injected in the scalp

For more, visit Hair Restoration of the South 

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