Anastasia Nu-Brow: is it possible to get thicker eyebrows?
The secret sauce in Nu-Brow is called Capigen. This is mostly a concoction of amino acids and emollients. Amongst them, however, are a couple of promising ingredients. Ultimately, I was disappointed: on closer investigation neither are entirely convincing. One is homotaurine, also called 3-aminopropane sulfonic acid. This is an analogue for GABA, the ingredient that is cropping up in face creams as a neurotransmitter (it is supposed to inhibit muscle movement). Hmm. After much rummaging, it appears that homotaurine is used in hair care products fairly frequently. I couldn't really find any evidence that it promotes hair growth, although there are some (unsubstantiated) claims that it slows hair loss.
The other potential brow booster is biotin. A vitamin B7, it is used in several hair loss treatments. However, there is no evidence that it works and topical application is likely to be effective since biotin can't be absorbed through the skin.