Our team is very focused on the science behind going grey and ways to support hair health. The formula for Not Today, Grey was created by an internal medicine MD, a dietitian and a chemical engineer from MIT. All of the ingredients have been researched and studied, including FoTi. Our formula contains 10mg which is well within tolerable limits. A 2014 NIH study found that issues with FoTi and the liver occurred in very high levels of FoTi at 1-100g (our level at 10mg is 1/100 of 1 g), so it is extremely unlikely that anyone taking 10mg would experience liver toxicity.