[vimeo http://vimeo.com/19170116]

Scientists have found that certain foods affect the brain and the way it responds to the hormones which regulate the appetite, but there are ways to outsmart the physiological triggers to overeat.

Expanded transcript from video… We all have a tendency to overeat once in awhile or perhaps it’s more than just once in a while – especially around the holidays.  But the good news is, scientists have discovered one of the reasons why – and it all has to do with the types of foods we eat. New research shows that saturated fats crank up your appetite.  They found that not only do they affect our waistlines, but our brains as well.

This meal, for example, contains lots of saturated fat from the beef, butter-glazed carrots, and sour cream and butter.  After just 3 days on a diet high in these fatty foods, studies found that the brain doesn’t respond right to the hormones that signal you’ve had enough to eat.  And this effect can last several days.

Leptin is a hormone made by the fat cells that tells you when you’re full.  If you don’t make enough leptin or your brain doesn’t respond to the leptin, you ending up eating too much.   Also, levels of insulin increase when the pancreas senses sugar in the blood after eating.  Once the brain detects the insulin spike, it diminishes your desire to eat.

Studies on rats and mice found that after just three days on a diet high in saturated fats, their brains became insensitive to leptin and insulin.  However, unsaturated fats, like olive oil, did not have this effect.

Scientists theorize that this effect is the result of the physiology of starvation when the body burns its own fat for energy.  Through evolutionary history, the brain interpreted fat circulating through the blood as a starvation alert which thus, led to overeating.
By making simple substitutions though, you can trick your brain’s hormonal response and eat less.

  • For example, eat fish, such as salmon, instead of beef.  You can also opt for a vegetarian chili or pasta with marinara sauce.
  • Dip your bread in olive oil and balsamic vinegar or top it with tapenade instead of spreading it with butter.
  • For sandwiches, add a layer of avocado or guacamole instead of mayonnaise.
  • Pour an olive oil-based vinaigrette over your salad instead of creamy bleu cheese or ranch.
  • And reach for non-fat or 1% fat milk, yogurt, and cheese instead of whole.
  • Finally, enjoy some refreshing fruit as a snack or dessert instead of rich buttery pastries and ice cream.

After indulging in eating a lot of saturated fats, it may take several days for your brain’s hormonal signals to respond appropriately again.  But you really can reset your brain to outsmart the physiological triggers to overeat.  Sticking to a diet rich in olive oil, fruits and vegetables will help keep your appetite under control.

Source:  Joelving, Frederik.  (2009)  Lard Lesson: Why Fat Lubricates Your AppetiteScientific American.


Please enter your comment!
Please enter your name here