Oils do so much for us. Our forefathers valued oils tremendously, so much so that they used them in ceremonial celebrations. Kings of old were bathed in oils as a symbol of divine anointment. Presently, cultures still value oils enough to keep a constant supply of them in circulation. Before the industrial era allowed the extraction and refinement of oils from grains and seeds, cultures everywhere had extracted oils from the flesh of oily fruits, largely olives and coconuts.
Heat has an effect on food. Some foods are easy to digest, while others require one method or another to make the sugars, proteins, and fats unfold and soften up for our stomachs to handle them effectively. Fundamentally, cooking is an application of heating food not easily digestible in its raw form. Through the application of heat food becomes more easily digestible. Take sweet potatoes, for instance. Eating a sweet potato uncooked or raw is naturally a recipe for stomach aches. However, bake a sweet potato in the oven until they it is soft, and a digestible meal awaits.
Bottled oils are not in themselves whole foods. Instead, oils are more accurately considered as concentrated extracts of the original food. Oils do not come with carbohydrates, nor with proteins. Oils make up a type of macromolecule known as a lipid. As a macromolecule, oils are fatty acids, and come in a saturated form and an unsaturated form. Subjecting an oil to heat cooks it. Therefore, as heat rises, certain types of oils can begin to burn. Some burn sooner than others. One can determine the propensity of a type of oil to burn by its type and composition of fatty acids.
The smoking point is defined as the temperature level in which a particular oil begins to burn. As an oil burns, smoke trails rise from the surface of the oil. Coconut oil has a high smoking point, which means it can withstand a high temperature and is suitable for cooking. Olive oil, in comparison, has a relatively low smoking point. The propensity and ease with which olive oil burns suggests that olive oil is too unstable in its chemical composition and, therefore, suggests olive oil is an unsuitable oil for cooking purposes.
In this article, the author will explore the molecular dimension of various oils by examining what is currently known. Scientific understanding today lends a hand in determining the effects of heat on particular oils. In addition, evidence explores the effects of a variety of treated oils on cellular components. The author will also provide insight into which characteristics determine an oil’s vulnerability to heat.
Fatty acids have a generic structure; on one end sits a water-loving head, on the other end hangs a water-disliking/repelling tail. Simply put, when a droplet of oil is added to a body of water the oil pools together. As such, the tails shift around to avoid the water molecules, while the heads arrange themselves towards the water molecules. That is how and why oils are found to naturally separate from water. Yet they can still exist in proximity to water thanks to those water-loving heads.
The tails of such fatty acids are considered hydrocarbons; an assembly of carbon and hydrogen atoms strung out in a chain-like fashion. Carbon atoms attach to one another, creating a chain. The hydrogen atoms are paired with each of the carbon atoms, such that each carbon atom has at most two hydrogen atoms. In addition, the last carbon atom in the chain will have an additional hydrogen atom that seals up the chain, making a total of three hydrogen atoms attached to the final carbon molecule.
While the heads of the fatty acids are consistently the same, the tails vary in length and saturation. Saturation means that the chain of carbons are fully saturated with hydrogen atoms. There is no more room for additional hydrogen atoms in the hydrocarbon molecule. Due to its complete saturation, the fatty acid has a hydrocarbon tail that is completely straight. This configuration or look of the tail is specific to a saturated fatty acid.
An unsaturated fatty acid is a molecule in which its hydrocarbon tail is not fully saturated. A section within the hydrocarbon tail that is absent of hydrogen atoms and, therefore, requires the carbons to compensate with a double-bond is referred to as an unsaturated section. Not all the carbon atoms in the chain will bond with a consistent number of hydrogen atoms. Some of the carbon atoms will only bond with one hydrogen atom instead of two, leaving their electrical valence incomplete. This, in turn, causes the carbon atom to produce a stronger relationship and electrical charge with the adjacent carbon atom. Since both only have one hydrogen atom, the two carbon atoms are drawn to develop a double-bond.
In summary, the two carbon atoms create a double bond while the rest of the carbon atoms comprising the tail maintain their single bonds. The disappearance of the hydrogen atom propels the carbon atom to engage in a double bond with an adjacent carbon atom. However, while the carbons are fully saturated, they only have the capacity to generate a single bond relationship.
In respect to the shape or spatial configuration of the tail, the unsaturated section appears as a bend or kink in the flow of the chain. While a saturated fatty acid projects as a straight chain, an unsaturated fatty acid starts off straight but is forced at an angle by the carbon double-bond effect. This creates a sort of kink in the chain, providing the molecule with an entirely different characteristic.
Furthermore, a fatty acid may have more than a single kink in its tail; it can have three and even more. A monounsaturated fatty acid (MUFA) has a single unsaturated kink; mono means single. A polyunsaturated fatty acid (PUFA) has two or more unsaturated kinks; poly means many.
While coconut oil is comprised of ninety percent saturated fatty acids (SFA), olive oil is comprised of roughly seventy percent monounsaturated fatty acids. Oils with a high percentage of polyunsaturated fatty acids include fish, flax, and hemp oils, as well as corn, safflower, and sunflower oils.
During processing all oils are removed from their natural settings, from a raw form into a concentrated extract of pure oils. They each respond differently to environmental stressors such as heat, light, and oxygen. Saturated fats, like coconut oil, have a higher smoking point and as such can withstand the high temperatures of cooking. Unsaturated fats, like the mono-unsaturated and poly-unsaturated oils, have a lower smoking point and are therefore less resilient to environmental stressors.
Every specific type of oil has a unique consistency at standard room temperature. Coconut oil, for example, has a high melting point, whereby it remains solid at standard room temperature (i.e. around 21°C (70°F)). This is unlike olive oil, which retains a thick liquid consistency at standard room temperature. Polyunsaturated oils such as sunflower oil, corn oil, or soybean oil, operate differently. When it comes to these types of polyunsaturated oils, a runny consistency, similar to water, is noticeable, rather than the thick consistency that is apparent in olive oil.
There is a significant difference in how oils are handled and stored. Coconut oil can be left out on the countertop, while olive oil is best kept in an opaque bottle or in the shade and darkness of a cupboard. On the other hand, fish, flax, and hemp oils are best kept in a sealed opaque container in a fridge. This is due to the high level of sensitivity of these oils. Due to this chemical/structural instability oils such as fish and hemp must be stored in tight conditions to prevent rancidity.
Olive oil can spoil or go rancid if exposed to heat, light, and oxygen (i.e. environmental stressors). However, it is the PUFA oils which spoil swiftly, faster than olive oil. The fact that polyunsaturated oils spoil quickly, while oils high in saturated fats tend to keep for longer, suggests a chemical imbalance in the nature of the PUFA hydrocarbon. Quite possibly, the kink effect in the chain of the fatty acids could be a major factor in the PUFA’s sensitivity to environmental stressors.
To better support the claim pertaining to whether the hydrocarbon kink confers vulnerability to the chain, let us delve into a study for further insight. This study produces further evidence to support an additional claim in which particular oils may have adverse effects on cells, human or animal alike, when ingested in large amounts.
Mitochondrion. 2011 Jan;11(1):97-103.
Dietary fatty acids and oxidative stress in the heart mitochondria.
Our study compared the effects of different oils on oxidative stress in rat heart mitochondria, as well as on plasma parameters used as risk factors for cardiovascular disease. The rats were fed for 16 weeks with coconut, olive, or fish oil diet (saturated, monounsaturated, or polyunsaturated fatty acids, respectively). The cardiac mitochondria from rats fed with coconut oil showed the lowest concentration of oxidized proteins and peroxidized lipids. The fish oil diet leads to the highest oxidative stress in cardiac mitochondria, an effect that could be partly prevented by the antioxidant probucol. Total and LDL cholesterols decreased in plasma of rats fed fish oil, compared to olive and coconut oil fed rats. A diet enriched in saturated fatty acids offers strong advantages for the protection against oxidative stress in heart mitochondria.
The abstract of this study seems to speak for itself. Coconut oil has beneficial effects on animal mitochondria; fish oil caused an elevation in oxidative stress. Since the mitochondrion is the cell organelle tasked with producing energy for the cell, less oxidative stress would allow the organelle to continue uninterrupted and in a care-free environment. On the other hand, high oxidative stress interrupts the mitochondrion’s flow of work.
Free radical stress can damage cell components and its organelles leading to changes in cell behavior. It is critical for cells to keep up with the production of free radicals by neutralizing them at a beneficial rate. If this does not occur, stress overtakes the cell and injury occurs. Once this happens, the cell must slow down its performance and upregulate repair and recovery pathways. If one is concerned with cell performance, then it is well enough to suggest that certain oils may impact performance adversely, while others may benefit.
Perhaps there is a connection between the number of kinks in a fatty acid to the level of oxidative stress within the oil or cell. This study suggests just such a case for consideration. It appears that the double-bond kink in the fatty acid reduces resiliency to the presence of environmental stressors. The presence or utilization of such sensitive molecules within the mitochondrial respiratory pathways could very well lead to the spawning of free radicals. Possibly, the more kinks in a fatty acid indicate a less stable fatty acid. Consider this in terms of the movement of a fatty acid through its various biological processes within the body, such as digestion.
If this is the case, one can easily recognize the connection between oils going rancid and an increase in free radical concentrations in the blood and tissues of the body. It may very well be that the process of oils going rancid is related to the impact of environmental stressors on the sensitive unsaturated sectors of the fatty acids. These unsaturated fats may have a lower molecular integrity, and as such crumble underneath that stress.
In full consideration of the knowledge covered so far, olive oil appears to be a sensitive oil and one should be careful with how to store it and how to use it. Olive oil may not be as sensitive as polyunsaturated oils, since it is mainly composed of monounsaturated fatty acids that render it moderately sensitive. However, because olive oil does oxidize quite quickly when subjected to environmental stressors, it seems to be best kept cool and used in cold dishes, such as salads.
Oils are made up of fatty acids. These macromolecules have a molecular configuration whereby a water-disliking tail projects from a water-loving head. This tail can be straight, held in such a configuration by hydrogen saturation; the tail can also, however, come with kinks, causing the tail to bend at an angle. This kink and angle confer unto the fatty acid an unsaturated characteristic. The missing hydrogen atoms at the unsaturated sector appear to confer it a level of sensitivity to environmental stressors. In light of these factors, the fatty acids become vulnerable to the forces of oxygen, light, and heat. When these unsaturated sectors come in contact with these forces, they lose their balance, break apart, and become a destabilized by-product within their surroundings.
Oxidative stress can cause cell component and organelle injury. Biological processes may slow down, which in turn have the potential to affect the entire cell. A study in which rats were given different oils and whereby levels of oxidative stress had been monitored, revealed specific types of oils to be less harmful than others. Coconut oil, with a high saturated fat profile, had the lowest injury to animal cell organelles, while fish oil, with a high polyunsaturated fat profile, had the highest adverse effect.
The mitochondria, a cellular organelle, are the energy producing powerhouses of the cell. The appearance of oxidative stress within the mitochondria provide reason to suggest an impact to energy levels with a connection to a decrease in cellular performance. If one cell were to slow down, it is plausible that an entire tissue or organ could sustain an impact in its capacity to perform.
It is still safe to use oils. Consider, first, the important benefits that take place from incorporating specific oils into dietary habits. Secondly, understand how to store and use oils to prevent from consuming rancid products. Consciously reflect upon the knowledge disclosed in this article and incorporate the wisdom unveiled, in addition to other related research.
If one desires the vitality of health and an optimal functioning body, it is up to each individual to take responsible for the quality of substances consumed. Incorporate this wisdom. Encourage healthy cellular life. Choose to see this knowledge as a strategy on handling food in a manner which supports your overall health. Be the one to choose an appropriate oil for the appropriate occasion. This is a daily choice and practice that can only provide more benefit over time. Choose to use olive oil for cold dishes and coconut oil for cooking, not because someone told you to, but because it makes absolute sense to do so.
 Mitochondrion. 2011 Jan;11(1):97-103. doi: 10.1016/j.mito.2010.07.014. Epub 2010 Aug 5. Dietary fatty acids and oxidative stress in the heart mitochondria.
Acknowledgement and gratitude to Emily Rosewall for her hand in providing detailed editing to this article.