Eating fat doesn't make you FAT

Contrary to popular belief, eating fat doesn't make you fat.  The current nutritional buzz is focused on eating low fat foods, for every full fat food there seems to be a reduced fat, low fat, or fat free version of the same thing.  As a nation we are afraid of fat, yet still have sky high obesity and diabetes levels.  What if eating fat doesn't actually make you fat...

Now for a little science - you need a little science to back things like this up! Many clinical studies have been run trying to prove the fat-lipid hypothesis, which basically states that eating fat (particularly saturated fat) makes you fat, and eating cholesterol raises your cholesterol and both lead to heart disease and obesity.  Nutritional studies are difficult to implement because there are so many variables; however, time after time the fat-lipid hypothesis has been tested and has failed to show a correlation between eating fat and blood serum cholesterol levels and obesity rates.  The notion that eating fat makes you fat and eating foods that contain high cholesterol make your cholesterol rise seems to make sense, so when Americans were contracting heart disease at alarming rates in the 1940s and 1950s the Federal Government decided that they needed to do something for the greater good of the American population.  This resulted in the birth of the USDA Food Pyramid and nutrition guidelines.  The trouble is that through conjecture, they defined the rules of the USDA Food Pyramid and began to stress a low fat diet without determining that a low fat diet could actually solve the heart disease issues. 

It's all in the hormones...

There are 2 important hormones you need to know to understand how your body processes food. Insulin which is a hormone produced by the pancreas that helps the body use glucose. Insulin is a storage hormone giving organs access to blood sugar and then storing the rest of it as body fat.  The second hormone is Leptin which helps control appetite & makes you feel hungry or full.  (Lights Out: Sleep, Sugar, Survival by T.S Wiley with Brent Fromby, Ph.D.)

When you eat carbohydrate, the insulin in your body first fills the glycogen levels in your muscles and liver (short term energy stores), and then anything leftover is immediately converted into fat and stored for later(long term energy stores).  Eating carbohydrates causes your body to respond with a very high insulin response based on the amount of carbohydrate consumed.  The more carbohydrate you take in, the higher the insulin response your body sends to process the it.  Insulin's job is to take the energy from within the carbohydrate and use what it needs and then store all the rest as fat and cholesterol.  When your body is 'full' of both the short and long term energy it releases Leptin, the hormone that tells your brain to stop eating and regulates appetite. Fat and protein do not trigger high insulin responses in your body, and therefore do not contribute to the production of body fat - which is why eating fat doesn't make you fat but eating sugar does.

Today's chronic diseases related to insulin, like Type II Diabetes come from a lifetime of eating too many carbohydrates and becoming insulin resistant.  Your body becomes insulin resistant and keeps sending out more and more insulin in order to process the carbohydrates that are being eaten.  When Insulin is high your body cannot access body fat to use as energy, making it difficult to use (or lose) the fat that all of the insulin in your body is quickly storing.  Interestingly, although most proteins create a minimal insulin response, dairy protein, particularly whey creates a high insulin spike - another reason to reconsider where dairy plays in your diet.