5. Liver
Though liver is a great source of protein and iron, which are important for your body, it is also has high purine levels, which is bad for those who suffer from gout. Calf liver, in particular, is bad for gout, as it as the highest amount of purine per serving (460 mg, to be exact.) If you enjoy liver and you want to reap the benefits that it offers, you might want to consider chicken liver instead, as it has lower purine levels; however, only eat small amounts of this type of liver.