What are carrier oils?
Most of us know them as carrier oils, but they are also called vegetable oils and even fixed oils because they are not volatile like essential oils. All carrier oils are not vegetable oils, like emu oil and fish oil. Most carrier oils are vegetable oils derived from the fatty portion of a plant in the seeds, kernels, or even the nuts. They can be cold-pressed (mechanical), expelled (mechanical), or go through a solvent extraction (chemical). Cold pressing is preferable as it retains the highest nutritional value in the oil.
Most carrier oils are chock-full of organic acids such as oleic acid, palmitic acid, and stearic acid, which make them excellent emollients that nourish your skin and hair. They are used in cosmetics, cooking, and to dilute the more potent and highly concentrated essential oil. They are also used as hot oil treatments or a mixture of oils for that matter, so it may not seem like a stretch to use some of them as heat protectants, right? Well, here are a few favorites of some who swear by their ability to keep your hair protected from the heat.
- Grapeseed oil is said to have a high smoking point and adds shine to flat ironed tresses.
- Argan oil has been circulating the natural hair blogs as great for protecting hair when applying heat.
- Coconut oil is a popular for a heat protectant known for helping to repair hair damage.
- Shea Butter is considered a great heat protectant because of its thermal conductivity is almost as good as popular silicones used in most heat protectants, namely dimethicone and cyclomethicone.
- Sunflower oil is another oil with a high smoke point but suggested to just add to other natural heat protectant oils.
What are smoke points?
Now, it is time to put the lab coat on and see what is really going on with these oils and whether they can actually protect your tresses from the drying and possibly damaging effects of heat. Chemist Yolanda Anderson further explains carrier oils, their smoke points, and if they are really protecting our hair. Smoke points are called burning points in chemistry and it refers to the temperature at which an oil begins to smoke, become discolored, and decompose.
Oil smoke points
|Fat||Smoke Point °F||Smoke Point °C|
|Unrefined sunflower oil||225°F||107°C|
|Unrefined high-oleic sunflower oil||320°F||160°C|
|Extra virgin olive oil||320°F||160°C|
|Macadamia nut oil||390°F||199°C|
|High quality (low acidity) extra virgin olive oil||405°F||207°C|
|Virgin olive oil||420°F||216°C|
|Refined high-oleic sunflower oil||450°F||232°C|
|Semi refined sunflower oil||450°F||232°C|
|Olive pomace oil||460°F||238°C|
|Extra light olive oil||468°F||242°C|
Oils should never be heated to the smoking point, because it is believed that fats that have gone past their smoke points contain a large quantity of free radicals and a substance called acrolein, which contributes to a higher risk of cancer, according to Anderson. As a fat degrades, it also gets closer to its flash point, producing ignitable gases.
Using oils as heat protectants
According to the cosmetic scientists and writers behind The Beauty Brains, “Heat tolerance (in this case measured by smoke point of the oil) is only one factor to consider. You also need to look at how the product lubricates hair. You can experiment with oils if you want DIY heat protection but be careful: oils alone can create drag which could slow down the flat iron as it passes through your hair, so it could end up doing more damage. Good heat protectants should also help offset the drying effects of heat. Ideally you want a combination of glycerin or other moisturizers to lock in water and a low molecular weight polymer that can penetrate and help prevent heat from cracking the cuticles.”
Using silicones as heat protectants
Cosmetic scientist and NaturallyCurly contributor, Erica Douglas aka Sister Scientist, told us “Oils behave very similarly to silicones by creating protective barriers from bad things like heat…Some oils can remain intact at extremely high temperatures, but they are often the heavier oils that can weigh the hair down. This is why formulating chemists will combine synthetic ingredients like silicones with the natural goodness of oils to provide an improved customer experience when using the product.”
There are more factors to using a natural oil as your heat protectant than its smoke point. Yes, concern for not reaching or going over an oil's smoke point is incredibly important for your safety, but also consider using or incorporating ingredients that combat moisture depletion. Using pure oil without applying a lightweight leave-in conditioner or a lightweight moisturizer prior may not be the best option before using heat tools. Many heat protectant products contain silicones like cyclomethicone and dimethicone, which work extremely well at coating the hair and creating a thin, water repelling, heat-resistant coating. Yes, there are natural oils that act like silicones and will protect the hair from heat, but as Sister Scientist suggests there are some great products created using natural and synthetic ingredients to give you a great heat protectant. Whatever you choose to do, think about it and realize that the objective is to end up with gorgeous hair without heat damage.
What are your favorite heat protectants?