While there isn’t a recommended amount you should be getting into your diet (i.e. caffeine is not an essential macro or micronutrient, so it doesn’t have recommended levels), the “safe” level of caffeine consumption for adults according to the FDA is 400 mg. Most adults average around 200 mg a day, which is about 2 5-ounce cups of coffee, or one daily dose or tablet from the caffeine pills on our list.