Even though the harmful effects of consuming vegetable oil are well documented and proven, it remains a fact that the vast majority of people still use vegetable oil to cook with. As of yet, the mainstream has not caught up with revered researcher Ray Peat et al; writing mercilessly of their condemnation of PUFAs.

It is difficult to purchase food from restaurants and food packaging companies that havn’t used vegetable oil as part of their ingredients.

With the ease of availability for healthier fats, such as coconut oil, and ghee, there is no reason for you to use vegetable oil at home.

Booming Trade In Vegetable Oil

The Vegetable oil business is worth £977 million (UK) in 2018 and has grown by 3.77 % over this past year. IBISWorld also predicted the market to keep growing, although at a slightly slower rate due to the pursuit of healthier options.

The industry is in the mature phase of its life cycle. IBISWorld expects the industry’s contribution to the overall economy, a measure also known as industry value added, to increase at a compound annual rate of 0.3% over the 10 years through 2023-24……Most of the industry’s products are well established, but rising health awareness is prompting many food manufacturers to adapt the mix of ingredients they use to reduce saturated fat and trans fat content. [R]

Thyroid Pathways At Risk

PUFA’s (Polyunsaturated Fatty Acid’s) are detrimental to your thyroid pathways. This study shows that T3 production is limited when unsaturated fatty acids are in your body. T3 binding is worse the more double bonds, so Oleic acid* with one double bond is the least harmful, with Linoleic acid having two double bonds and Linolenic acid having three. There is another PUFA to be found in non ruminant animals that contains 4 double bonds and this fat is Arachidonic acid. Read more about PUFAs here.

(Inhibition of T3 binding) by unsaturated fatty acids was greater than that of saturated fatty acids, and increased with increasing number of double bonds. [R]

PUFA Oxidises Easily

PUFA is easily prone to oxidation which makes the oil toxic. Heating the oil accelerates the oxidation process.

The oxidative advance of PUFAs during heating was studied by the determination of unsaturation percentage at different temperatures and heating times. Oils frequently used in food frying such as olive oil, sunflower oil, corn oil and seeds oil….This variation in unsaturation grade provides evidence of the transformation of …. PUFAs and subsequent decrease in the oils’ nutritional value. [R]

Brits Love Chips

Another study measured the peroxide content when repeatedly using the same oil to fry potato chips.

I can remember when my mother would keep the same fat in the chip pan for days. This was not such a problem with tallow.

These days, it’s more likely to be vegetable oil in the chip pan. Consider this; how many chip shops use vegetable oil? How many use the same oil day after day?

keropok lekors (potato Chips), when used as the frying material, increased the peroxide values of the palm and soybean oils. [R]

Peroxidation is when the oil becomes very hard to digest and reality, toxic.

One Cell At A Time

PUFA has been shown to escalate the rate of cell death. This study in vitro measured how cells were affected by PUFAs at different stages. Cells need fat to survive, but polyunsaturated fats can choke cells in to death.

On the fourth day, 80% of the PUFA cells were dead while the reference strain had 22% of dead cells….One of the main features of the PUFA strain is its high level of ROS (reactive oxygen species).[R]

Altogether, we highlight that the potential harmful effects of dietary oxidized n-3 PUFA, even if consumed in moderate doses, should be taken into account in several pathologies. It appears of utmost importance in medical and nutritional practice to formulate and handle n-3 PUFA-rich foods or supplements with the greatest care to avoid any PUFA oxidation. [R]

Even if you manage to consume a PUFA laden oil while it is still fresh, inside your digestive tract the oil will be subject to exposure by your enzymes. This results in peroxidation inside your body.

Polyunsaturated fatty acids are a major target for oxidation by ROS, a process called lipid peroxidation (LP), which disrupts normal membrane structure. [R]

Unsaturated FAs Inhibit Detoxification

Glucoronidation is a process where glucose is combined with other components to create glucoronic acid. This pathway is essential in order to effectively eliminate substances that are not useful to the body. Most difficult to eliminate toxins are stored in fat. This pathway converts the fat stored chemicals into water soluble. They can then be easily eliminated via urine.

A study in 2004 concluded that during times of kidney inflamation, unsaturated fatty acids may impair renal glucoronidation thus compromising the protective capacity of the kidney. [R]


It has been known for decades that PUFA oils are easily prone to oxidation and rancidity. However, due to the relatively cheap and easy manufacturing ability, producers have sought ways to extend the shelf life. We can at least benefit from this research to shield ourselves. Sign up now to receive the Protect Yourself From Pufa guide.

As long as people keep buying it, or consuming it in restaurants or in packaged food then companies will keep selling it. It’s up to consumers to let business owners know they are unhappy. Until there is enough of a movement then people will suffer unnecessarily with poor health.

These studies suggest that maybe a bottle of vegetable oil should contain a health warning.

You can protect yourself to a certain degree from unwanted exposure to PUFA by regular consumption of certain foods and vitamins. Join our program and get a free Protect Yourself From Pufa guide.

*Oleic Acid is strictly a monounsaturated fat as it contains just one double bond.


Leave a Reply