resistance and an increase in fat storage,
accompanied by greater insulin resistance.
Leptin is sometimes referred to as a
“satiety hormone,” because higher leptin
levels help to keep us full and satisfied.
Leptin levels follow a normal daily cycle tied
primarily to your eating schedule. Since you
don’t eat while you’re asleep, leptin is pretty
low first thing in the morning. This triggers
the secretion of appetite-stimulating
hormones and is one of the reasons we wake
up hungry. When you’re done eating for the
day (typically after dinner), leptin levels are
higher, helping you stay full and satisfied
until bedtime.
However, leptin’s primary job is to
regulate your big-picture hunger and activity
levels to help keep your body in “energy
balance”—not too fat, not too lean. Body fat
is not a bad thing—it’s what allows us to
survive long periods of food shortage (or to
not eat for a few days when we have the flu).