Here is the skinny on fats
What are fats and why do I care?
Fats, they have become bad words in modern society eating modern diets. The trouble is that they have kept us alive and healthy for millennia. Breast milk is the super food that it is because it contains both high cholesterol for brain development and 4% fat by weight to keep baby full longer between feedings (just ask any mother who has breast fed about that inherent benefit at 3 AM).
However, along about the 1950’s food production was already highly mechanized and becoming more processed when a researcher by the name of Ansel Keys developed the Lipid Hypothosis. In case you are not conversant in dietary theory, here is a great graphic from New Trends Publishing that Sally Fallon Morell uses in her Oiling of America DVD to explain it:
Original slide can be found at: http://newtrendspublishing.com/ppts/OilingofAmerica.ppt
The problem with the Lipid Hypothesis is that it was constructed on flimsy–or to be charitable–incomplete science. Nevertheless, it was a counterpart to some great marketing forces and the low-fat trend was born. The only thing worse than fats to a lipophobe (a term that I believe was coined by Michael Pollan) is saturated fats from animals. So before the low-carb trend came along, we had low-fat (neither of these are healthy by the way) and somehow what supported vitality in people all the way down to the cellular level was discarded. Keep an eye out for this when you watch tv or read magazines. The temptation is to equivocate real bread with the shelf-stable imposter you see in the grocery store. In the same way using broad strokes like that, you get that treatment in something like this (although I agree with the discussion on fats):
Here is a better question, what are fats? From a food chemistry stand point, most of the fats we eat are called triacylglycerols (root word there being “acyl;” although triglycerides are the same thing, the former is the better descriptor) (Joachim & Schloss, p. 220). Fats are substances that are not water soluble, but make food interesting and give it a pleasing texture to your mouth, are a concentrated energy source, are the building blocks for cell membranes, are the carriers for the überimportant Vitamins A, D, E & K, are needed for mineral absorption, for the conversion of carotene into Vitamin A and most notably fats are the mother of all hormones (Fallon & Enig, p. 4). Take this other slide from Sally Fallon Morell’s DVD, The Oiling of America:
Original slide can be found at: http://newtrendspublishing.com/ppts/OilingofAmerica.ppt
It is my hope that I can establish the necessity of fats in a healthy diet and that a low-fat diet is not healthy not only because it does not contain fats, but because it also contains lots of chemicals that are very unhealthy—more on that for another blog. Put more succinctly by Sally Fallon Morell in her presentation, The Oiling of America, Blaming fats and high cholesterol is like blaming fires on firemen. Every time we see a fire, we see a fireman so the premature unscientific conclusion is to blame firemen for fires (Morell, 2008)
If we delete if [fat] from our diets, we subject ourselves to nutritional deficiencies as we would lose our ability to absorb fat-soluble vitamins and valuable phytonuturients (lutein, lycopene, beta-caotene, and vitamins A, D, and E). Fats are a integral part of cell membranes and the production of hormones, and they are essential for brain development and activity and the workings of the nervous system and liver. The problem in industrialized culture is that we tend to take in too much of the wrong kinds of fat, which can have negative consequences on our health (Joachim & Schloss, p. 118).
“I have heard that saturated fats are bad for you, what are unsaturated fats—are they better for you?” The answer is, it depends . . . let us make sure we are talking about the same thing first.
Saturated fats can be short, medium or long chain fatty acid compounds. Or put another way, all short and medium chain fatty acids will be saturated and some long chain fatty acids can be saturated—it is more like a continuum than anything else. What makes it short or long chain is the number of carbon atoms in the molecule. As an analogy, the difference between butane and diesel fuel (generally speaking) is the number of carbon atoms in the particular hydrocarbon molecule with methane having the fewest and tar having the most. On that continuum in ascending number of carbon atoms in the chain are: gasoline, diesel fuel, gear oil, paraffin candle wax, etc. all with different numbers of carbon atoms in the chain affecting their molecular weight and physical properties as a compound.
The big difference between fats and oils are how we observe them at room temperature, and saturated fats are a solid at room temperature. Another interesting fact about saturated fats is that they are very stable and perform the best in cooking as well—more on that in this blog. Back to the comparison, your body can make saturated fats if need be as a function of the liver by digesting complex carbohydrates (hence the hydrocarbon analogy).
Unsaturated fats are what we observe as a liquid at room temperature. Not all unsaturated fats are equal and of these my personal favorite is olive oil! The unsaturated fats do not stand up to heat as well as saturated fats, and they can go rancid quickly in warm humid environments because they are comparatively unstable. By unstable I mean that they will look to fill up those blank hydrogen places in a process called known as oxidization. The category “unsaturated fats” is actually subdivided into monounsaturated and polyunsaturated.
Monounsaturated is the preferred group for us here at Pantry Paratus because they are the closest to what you can find in nature and (unsurprisingly) you body knows what to do with them. Polyunsaturated fats have two subcategories as well, essential and conditionally essential (although not opposed). Some of these oils your body cannot make are called “essential oils” and are found in nature in fish, fresh herbs and some kinds of seeds—but not all polyunsaturated oils are the same. “The two must-haves for essential fatty acids are omega-6 linoleic [sic] acid and omega-3 alpha-linolenic–and there are several other conditionally essential fatty acids (Fallon & Enig, p. 306).
“I heard my doctor tell me to stay away from trans fats, what are they?” These are the imposters . . .
When you need a pastry to have the flakiest crust nothing performs better than lard or tallow—these are made from rendered pig fat and cow or sheep fat, respectively. These are the gold standard of fats since they do not oxidize–they are stable, keep for a really long time and are very pure. However, keeping pigs can be a hassle, and would it not be just so much easier if we could just pump hydrocarbons out of the ground or genetically modify some oil seed plant instead? Amazingly this is where a lot of trans fats come from and knowing this helps us have a more informed answer to the question, “What are fats?” The answer will depend on the kind of fat you are talking about.
Where saturated fats are short chain fatty acid compounds, they exhibit the characteristic of having all of their carbon atoms filled with hydrogen atoms making them “flat and easy to stack” together which we observe as a solid at room temperature. Monounsaturated fatty acid compounds lack two hydrogen atoms making them have a slight kink in the molecular shape so we observe them as a liquid at room temperature. The danger with trans fats is that they (heavily) process the fat to accept a hydrogen atom where it was not meant to be (we rarely observe this in nature). This gives the new hydrogenated oil a physical performance like lard and a high smoking point like lard but is essentially a huge health risk on the cellular level once it is in your body. These hydrogenated oils are free radicals, and they will oxidize or steal electrons from your body’s tissue to “complete” themselves. Compounded over time, this is a huge problem in your body because your cells depend on cholesterol to repair themselves. When all your cells have to work with is imposter fats, the results can be devastating because they are accumulative over time.
The “trans” in trans fats is from the molecule straightening back up from its normal “kinked” shape (or “cis” formation) as a polyunsaturated fat. The process renders this polyunsaturated fat that was once a liquid as a solid at room temperature. Since polyunsaturated oils will go rancid at high temperatures, they must be “deodorized” in a process using heat—seems like a catch 22 but it is the method that they use. During this deodorizing step, one hydrogen atom is forced across (or trans) the molecule causing it to straighten out again making the molecular misfit transformation complete.
“What is the difference between hydrogenated and partially hydrogenated?”
The best answer for this that I have read is in the amazingly funny and informative book Twinkie, Deconstructed by Steve Ettlinger. In there he goes to an industrial plant where from the looks of it they may have been making paint or perfume, but actually it was full-hydrogenated oil (or “full hydro”). Like lard, it is a solid at room temp, and will not flow unless it is heated up. So as it is dispensed into train cars for transport it is in a warm liquid state. When the train car arrives at the food processing plant as an ingredient for the now defunct Twinkie® it has to sit there hooked up to a steam pump to heat up the steam jacketed rail car so that the hydrogenated oil can flow again. This is probably why it was originally sold as a candle wax alternative.
Cholesterol in your body is actually necessary and a good thing designed to be there. When saturated or monounsaturated fats are incorporated into a healthy diet, the body is able to carry out cellular functions, keep nervous system activity running optimally, deal with stress as well as provide hormones and the reproductive system the high octane fuel that they need. Trans fats are imposters because although Crisco looks like lard at room temperature, it is a marauder inside of your body in the form of being a free radical.
Pro Deo et Patria
- Lipid Theory by Sally Fallon Morell, New Trends Publishing. Can be found here
- Cholesterol, the Mother of all Hormones by Sally Fallon Morell, New Trends Publishing. Can be found here
- Engine Oil: photo credit: brionv via photopin cc
- Monounsaturated Fat: photo credit: USDAgov via photopin cc
- What are Fats by Pantry Paratus compiled from images from the public domain, the WAPF and information from Nourishing Traditions (cited above)
- Crisco: photo credit: tellumo via photopin cc
Fallon, S., & Enig, M. (2005). Nourishing traditions. (Deluxe Edition ed., p. 4). Washington DC: NewTrends Publishing.
Morell, S. (Presenter) (2008). The oiling of America [DVD].
Joachim, D., & Schloss, A. (2008). The science of good food. (p. 220). Toronto: Robert Rose.
- Weston A Price Foundation Article on Cholesterol, friend or foe?
- A good graphical rendering of fatty acid compounds
Nothing in this blog constitutes medical advice. You should consult your own physician before making any dietary changes. Statements in this blog may or may not be congruent with current USDA or FDA guidance.