Saturday, February 9, 2013

What Type of Fatty are You?

Hello people! Last week I did a blog about nutrition and my take on the components of a healthy diet. I specifically discuss fats and I got a few questions about what fats are good and what fats should people avoid. People seem generally confused about fats and lipids and how all of that stuff works. We are told we should avoid them, but not which kind or how much.  Hell, I don't even know all the different types of biologically active fat out there. This is some complicated stuff. I am going to try and explain this in general terms through a toxicology/ pharmacology student perspective. See, pharmacology/ toxicology is kind of like Latin. While Latin gives you the basic vocabulary to assemble complex words, pharmacology/ toxicology gives you the very basic understanding of chemical reactivity in a biological system. This means even if you come across a chemical or word you are unfamiliar with, you can break it down into basic components and guess what it means.

Alright, let's start with the concept that there are different types of fats. Great! We are off to a good start! But now we must go deeper! Fats are composed of lipids. These lipids are composed of fatty acids. There are many different types of fats that can be compositionally broken down into a blueprint of different fatty acids. In this blog I hope to educate you on the different types of fats and fatty acids that you are consuming on a daily basis!

Saturated Fats vs. Unsaturated Fats
 Ok. I know you have all heard about saturated fats vs. unsaturated fats, but it is time you learn the difference between the two. The difference is in the chemistry. Saturated fats consist entirely of single bonds, whereas unsaturated fats contain at least one double bond. This chemical variance results in a difference in physical properties. Saturated fats are generally solid at room temperature and unsaturated fats are generally liquid at room temperature. Another way to think about this difference is fats vs. oils. Oils are liquid at room temperature, like unsaturated fats. Fats are solids at room temperature, like the fat found in your beer belly.

For those of you with no background in chemistry I'm going to break this down like an ion in water. Those with a strong chemistry background please skip this paragraph and save yourself from painstakingly boring details. Chemicals are held together by different types of bonds. Since we are dealing with organic molecules (carbon containing) we are dealing with mostly covalent bonds. Covalent bonds involve two atoms share electrons. So that carbon and that hydrogen you see in that fat diagram above are sharing electrons. Now, carbons have four electrons to share. So, they can share one, two, or three of those electrons with another carbon (it can only share one electron with a hydrogen due because hydrogen doesn't want any more then two electrons, whereas most molecules wants eight). If it shares one electron with another carbon you get a single covalent bond. As you see in saturated fat diagram each carbon is sharing one electron with each carbon resulting in single bonds all across the chain. If a carbon shares two electrons with another carbon you get a double bond. This double bond is three-dimensionally different that the single bond. This results in the observed differences in physical characteristics (liquid vs. a solid). Sweet jesus, who knew chemistry makes so much sense! 

You find high levels of saturated fats in animal products (except chicken and fish) like red meat, cheese, and milk. You will also find saturated fats in tropic oils like cocoanut or canola oil. Unsaturated fats are found in fish, chicken, olive oil, avocado oil, soybean oil, nut oil, and sun flower oil. Unsaturated fats come in two different forms, monounsaturated fat and polyunsaturated fats. Monounsaturated fats have one double bond and are in vegetable oils, such as canola, olive, and peanut oils. Polyunsaturated fats have multiple double bonds and are found in fish, soybean, and sunflower oil. 

But why is one fat better than another? Now what I'm about to tell you will blow your mind. You are what you eat. Bam. Seriously, the fats you consume are often the types of fats you will find in your body. So if you eat a great deal of salmon, you will taste like salmon. Neat shit, right? That means you will have different biological activities based on the different fats you consume. Since these fats are physically different, they have different biological consequences. Here is where it starts to get tricky. There are many different opinions on the biological activity of different fats. Unsaturated fats are considered better for you because they are more easily absorbed and metabolized in your body. However, the biological consequences of having a faster absorbed and metabolized compound is still in question. I am going to quickly talk about the specific biological activity of two fats that are commonly discussed in the media, omega-three fatty acids and arachidonic acid. There are obviously more fatty acids out in the world then those I will discuss. If you come across a fatty acid you have never heard of and don't know the structure, I encourage you to, yet again, google that shit.

Fish Fat and Aspirin

I'm sure you have heard all the great things about omega-three fatty acids, and most of it is true. Studies have actually shown that these fatty acids can protect you from neurological damage and cardiovascular disease. This translates to potentially helping with diseases like depression, congestive heart failure, and ADHD. I will also discuss below the consequence of intaking omega-three fatty acids oppose to other fatty acids. This is all well and good, but there is something really bothering me. What about the toxic effects? Like I have said before, every chemical has a therapeutic and toxic threshold. The therapeutic effects of omega-threes are becoming well studied, but the data on toxic effects of omega-threes are weak. If I had to guess, you would most likely get some sort of methyl-mercury poisoning (or some other fish toxin) before you could OD on fish oil. I'm also sure it isn't common to find someone gorging themselves on shrimp in their basement, but stronger toxic studies need to be done considering people are now supplementing fish oil like it is candy. So, yes, eating fish fat is good for you. I would simply advise not popping fish pills until someone can give a definitive toxic dose for fish oil.

Less of you have probably heard about arachidonic acid, which is a shame because it is a fascinating little fat. Arachnoid acid, also known as omega-six, is a polyunsaturated fatty acid commonly found in peanut oil. It is the most abundant fat in your brain, is necessary for muscle repair and growth, and can be completely synthesized by your body. So, even if you don't eat peanuts, your body will make arachidonic acid all on its own. What is unique about this fatty acid is that it is involved in the biological pathway for inflammation. Inflammation is that painfully hot red swelling you get after you stub your toe, get a bee sting, or have a headache. When a cell encounters a potentially hazardous foreign compound it will convert arachnoid acid to various prostaglandins (types of fatty acid metabolites) which signals to the surrounding cells to activate the inflammation response. This inflammation response involves summoning copious amounts of blood to the site (red swelling) and activating immune cells to kill off any foreign substances that might have triggered the response. This actually a proposed mechanism of meat sweats. You increase your intake of arachidonic acid and as a result you stimulate a weak inflammatory response. You become flushed, hot, and you feel bloated (swelling). The inflammatory response is essential in the healing process, but it can also cause all sorts of damage if over stimulated. Therefore pharmaceutical companies have developed methods to shut off this metabolism by stopping the metabolism of arachidonic acid into prostaglandins. The most popular drug they use to inhibit this pathway is aspirin. That's right, aspirin. It stops this metabolism bly blocking an enzyme name cyclooxygenase (COX, no I am not making this shit up) resulting in an inhibition of the inflammatory response. Many people have also tried to replace arachidonic acid from their system by supplementing omega-three fatty acids in their diet. The omega-threes substitute the omega-sixes in the phospholipid membrane, where these lipids are stored, where they will remain since omega-threes won't be degraded into inflammatory products. How freaking cool is that! You can actually change the efficacy of aspirin or your reaction to a bee sting by simply changing your diet. Blam. Science.

Processed Fats
I have a whole section for processed fats because they are such a hot topic in the media today. We all hear about how trans fats are bad for us, but what are they? They are fats that have been processed beyond their normal structure. There are two types, hydrogenated and unsaturated trans-fats. The hydrogenated fatty acids are taken from unsaturated fats and transformed into saturated fats by adding hydrogens. Unsaturated trans-fats are unsaturated fats that have their double bond in the trans transformation. This type of double bond is not found in naturally occurring fats and physically looks different to its cis-formation counterpart. These transformations increases the food's shelf life, gives food a more firm texture, and also makes breads crackers crispier and flakier. These types of fats are found in processed foods like margarine, cookies, and a percentage of corn oil.  The reason these types of fats have gotten so much press is due to the biological consequence of physically changing a fat's structure.  The major consequence being lowering your HDL (high density lipoprotein) and increasing your LDL (low density lipoprotein). Now I can go into an entire blog about why increasing HDL is good and why increasing LDL is bad if you guys want, there just ain't time to get it all done in this section. Just let me know in the comments if you want more on HDL and LDL. Basically, the major result in increasing LDL and lowering your HDL is elevating your risk for congestive heart failure, obesity, and diabetes down the road. So basically, don't eat trans fats. Shit is so bad for you. Again, I can go more in detail on this topic specifically, but this post is already long and I want to save some good stuff for later.

Now you are an expert in fats. Or at least you have a very basic understanding about fats. Go to your grocery store now and look at some of the fats in your food. I'm not even kidding. See what types you are consuming. How much of it is trans? How much of it is unsaturated? Then you can go further and determine what types of fatty acids are in the fat you are consuming. Do some research. Figure out what you are putting in your body! Most of all, never stop educating yourself!

1 comment:

  1. so...if you are what you eat & you eat sugar--what kind of fat does that turn into? also--how difficult are the different fats to turn into energy, when needed?