Thinning hair may be the mortification of every man, but no one seems to ever want to talk about it. Certainly, no one seems to ever want to be seen doing anything about it. Yet a natural hesitation for synthetic hair-spurting chemicals may be a good thing: Over-the-counter topical solutions like Rogaine are creepy and obvious, while prescription drugs like Propecia have been linked to erectile dysfunction (we're guessing Justin Bieber didn't know that when he recommended the drug to Prince William). But what's the alternative if you'd rather have Biebs' hair over the receding mop of the British prince?

Hair-loss supplements are like weight-loss supplements: There are plenty out there, but few offer proven science that they work. So we were surprised when Reserveage Organics Keratin Booster for Men actually made our hair feel fuller, thicker, and "heftier." Yes, it costs $45 for one month's supply, but that's because it packs a good dose of the new, advanced Cynatine HSN – a natural form of keratin, the main fibrous component of hair, that studies show can cut hair loss by up to 30 percent. The supplement also contains biotin, key to hair health, along with resveratrol, beta sisterol, and saw palmetto, all three of which support normal levels of DHT, a male hormone that causes hair loss.

What really sold us on Keratin Booster, though, is that it contains organically derived ingredients that can help boost your overall health, regardless of the hair on your head. Resveratrol and beta sisterol have been shown to help lower "bad" LDL cholesterol, while saw palmetto can help fight the symptoms of an enlarged or infected prostate, according to research. The supplement also includes quercetin, an antioxidant shown to inhibit cancer growth. So even if Keratin Booster does nothing for your hair, which we find highly unlikely, it'll still be doing something for you health. Pick up a bottle at Whole Foods, The Vitamin Shoppe, or other supplement retailers. [$40; reserveage.com]