Why America Is Fat.

So reading the title I am sure some will think.. Oh, that's because Americans are lazy, over indulgent fools that don't understand eating greasy, fatty foods everyday and not exercising makes you obese. True, but what makes people crave these foods? And what happens in your body when you eat these delicious things?
Disclaimer: I love food and can't get enough of it.

If you think about it, it doesn't make sense that our bodies should crave these foods that hurt our bodies thinking about humans as animals in a evolutionary sense. You would think our brains would adapt to not enjoy the taste of fatty foods if it ends up shortening your life.. simply because our aim in life is to survive, procreate, etc. This never happened because there was never a situation in the wild where sugary, fatty foods were so abundant. If cavemen saw how easy it is to get food, I think they would be pretty bitter about their longs lives of foraging.

You need some fat to survive. First of all, they serve as energy storage. The word calorie now has this connotation of some bad monster that people seem to be obsessed with 'counting', but I think people don't know that the word calorie is a unit of energy. 1 gram of fat gives 9 calories of energy. Energy is certainly necessary and fat molecules allow you to have back up energy to keep living. Second, the mass of fat protects organs and keeps us nice and warm. I could get into more reasons like it helps your body absorb nutrients and produces hormones, but as the first blog post.. I will try and stay focused on the topic at hand.

(Side note: How much fat do you need? http://www.myfatstranslator.com/)

Okay, so you need fats and we have all heard to always avoid the feared transfat monster. There are Four major types but let's simplify it to saturated (includes trans) and unsaturated fats. Unsaturated fats are the 'good' fats and are usually liquid at room temperature (ex. veg oil) and saturated fats are the 'bad' fats more solid at room temperature (ex. butter). The 'bad' basically refers to the way the molecules pack.. saturated fats end up being harder to break down/ make it harder to lose weight. Tran fats are even worse because they are basically man-made saturated fats put in food to increase shelf life of foods. Negative effect? It changes reactions during metabolism to increase the release of the bad LDL cholesterol into the blood stream, which then gets deposited into blood vessel walls. This can cause a whole mess of problems including, but not limited to, clogging arteries leading to heart disease. (This is already getting lengthy so I'm leaving out information on cholesterol)

Okay, so more information than you ever needed to know on fats, but I hope you are still reading. Getting back to the point why would we ever over eat? Why do we see a cookie and even if we are full we have to have it? People, myself included, seem to blame some mythical force saying things like "I can't help it." I have eaten an entire pizza by myself and I didn't want more then two slices!! Eating is fun, why?

A study was done titled "Deconstructing the Milkshake" where they tried to identify if fat, vanilla flavoring, cornstarch or sugar was the flavor that drives us to want to consume a vanilla milkshake. Sugar was found to be the driving ingredient when alone, but when fat and sugar are combined the drive increases like crazy. (This was done by giving rats each ingredient alone or paired and they would press a lever and essentially they would work harder pressing it more often when they loved the ingredient). So what does sugar do to our brains? It releases Dopamine a neurotransmitter released involved in focusing attention. This is important in times like if you were swimming and saw a shark. The instant you saw the shark Dopamine would be released to focus your attention on the shark.. this is different then adrenaline. So when you eat sugar, dopamine is released focusing you on the pleasing flavor and interestingly enough when sugar and fat are eaten together even more uncharacterized brain activity occurs with the dopamine release.

So when we see foods we crave, we get cravings based on a 'muscle memory' of your brain. Your brain sees the cookie that once caused a pleasing brain stimulation and dopamine is released focusing your attention on getting the food. The same way that your fingers get used to moving when playing say.. guitar hero.. and sometimes your hand seems to be able to do it on it's own from repetition. A cue like seeing food or seeing a location will cause the dopamine release and you crave the brain stimulation.

Dopamine is also released but stays elevated when taking drugs like cocaine or amphetamines. Food normally just causes one 'spike' of activity, but when food is more complex (really loaded ice cream Sundae) the activity mirrors the dopamine activity as seen with drug use. You can feel the same way about food desire as a crack head feels about needing a 'fix'. Crazy right?

Anyway, I hope that was interesting.. I think it is. Science blog ftw.