I have read many different articles discussing the pros and cons of caffeine. If the main goal is to lose weight, is caffeine a help or a hindrance to reaching that goal? (My vice is coffee!) And, is there a breaking point at which a certain amount becomes too much and particularly "bad" for dieting? Also, if you believe that caffeine is a hindrance, please explain the specifics as to why scientifically/biologically, etc.
Heavily sugared and creamed coffees may interfere with weight loss by adding calories, but caffeine is thought to help weight loss by increasing the metabolic rate and suppressing the appetite - ever so slightly for both. Current research is looking at whether large amounts of caffeine contribute to insulin resistance, which would hinder weight loss. Insulin resistance is when the body cannot use the insulin it produces to process blood glucose. Caffeine may increase insulin resistance by increasing epinephrine (also called adrenalin), a hormone produced in response to stress. It is not known if smaller amounts of caffeine affect insulin levels or if a tolerance is involved. For healthy adults, caffeine should be limited to 400 mg per day, the equivalent of about three 8-oz cups of brewed coffee.