Certainly it would be nice if we could flip some cerebral switch that would keep the leptin light on and permanently cut the power source to ghrelin. But what we do have is the ability to flip the switches (in either direction) through the foods we eat. Those foods - and the chemical reactions that they cause when they enter our bloodstream - can increase or decrease the effect of leptin and ghrelin.
Fructose, for example, which is found in high fructose corn syrup and in such devilish products as soft drinks and low-fat salad dressing, can cause your sensors not to receive the leptin message. That's because many of these processed foods we're seeing today are really imposter foods; your brain simply doesn't recognize them as real foods. The effect: As ghrelin goes up or leptin goes down, you reach for a fourth pepperoni stick. But if you eat real foods—foods like nuts, vegetables, whole grains, and lean animal protein—your brain gives your body a direct order: Let's close ship, sir, this one's had enough.
Find out more about this book:YOU: Having a Baby: The Owner's Manual to a Happy and Healthy Pregnancy