for asymptomatic gallstones you don't have to worry about it too much, for high blood pressure/high cholesterol, you do the routine, life style modification and risk factor reduction, quit smoking, watch diet, increase fibers and fruit content, lower sodium and fat intake, exercise, and if still not controlled then take meds, knowing all medicines have side effects , if it's the blood viscosity you are talking about, kind of want to rule out polycythemia, which could be a bit more complicated