A headline reads “vegetable oils are bad”. The next day another reads “vegetable oils are heart healthy”. Where does the truth lie? Here we meet again to discuss another controversial health related topic.

There is much to consider with vegetable oils such as omega-6 to omega-3 ratio, linoleic acid content, polyunsaturated vs unsaturated vs trans fat, smoke points and more. I am here to simplify it for you. I will define vegetable oils, discuss things to consider, outline the healthiest and safest options, and debunk a few myths. You will leave this page comfortable and confident with what you are cooking up in the kitchen.

What are Vegetable Oils?

Vegetable oils are derived from plants or seeds. They are often referred to as vegetable, seed, cooking, and/or plant oils. These oils came about in the 20th century and use has been increasing ever since. Initially they were deemed “heart healthy” alternatives to butter due to lesser saturated fat content. They may be used for cooking or to add flavor and texture.

Things to Consider

1. Smoke point– a temperature at which the product undergoes oxidation and breaks down to form potentially toxic free radicals. A higher smoke point means it is safer to cook with at higher temperatures.
2. Omega-6 to Omega-3 ratio– some oils contain greater levels of omega-6 to omega-3. Literature has found higher ratios may lead to increased inflammation, increasing risk of many disease states.
3. Unsaturated fats– fats encompass 25-30% of daily caloric intake. Consuming healthy fat is crucial. More unsaturated, less saturated and no trans fat is ideal. Check out my post on macro and micronutrients for more info on this https://lrxwellness.com/macro-and-micro-nutrients/
4. Linoleic acid– polyunsaturated fat, primarily omega-6 may be consumed in moderation.
5. Extraction/Refinement process– high temperature extractions may lead to less pure oils and potentially harmful byproducts.
6. GMOs– how the product is grown and produced. Genetically modified organisms (GMOs) may be worth avoiding. Products like corn are often GMO.

Which Oils are Healthy and Safe

Below you will find the most and least healthy/safe vegetable oils.

Yes– high smoke point, healthy unsaturated fats, high in antioxidants, more omega-3 than omega-6.

In Moderation– high smoke points, unsaturated fats, may have higher omega-6 than omega-3

No– some do have high smoke points but many do not, the extraction process makes the product less pure, more saturated and possibly trans fats. Of note, while some of these oils are not “bad” it may be difficult to find a pure formulation.

MYTH	TRUTH
All vegetable oils are bad	No, not all are equal and bad. As outlined above there are many factors to consider.
All vegetable oils are heart healthy	No, not all are equal and healthy. Again, there are many factors to consider.
Vegetable oils cause cancer	No, they themselves do not cause cancer but the temperature at which they are extracted, refined, processed and/or cooked at may cause breakdown and production of toxic free radicals. And yes, these byproducts have the potential to cause cancer.
Butter is bad	Heck no! While it is higher in saturated fat, it also contains healthy unsaturated fat, like omega-3. Consumed in moderation butter can be part of a healthy, well-balanced diet.

Bottom Line

Vegetable oils are not all equal and they are not all bad! Or good for that matter. The rumor that vegetable oils cause cancer only applies when they are extracted, refined, processed and/or cooked at high temperatures making them unstable, forming toxic free radicals. Just as all oils are not equal, not all product is equal either. Quality and processing matter. The safest and healthiest options appear to be olive and avocado oils. Other options may be consumed in moderation. And some are best to avoid all together. Select your vegetable oils carefully and don’t be afraid to throw in some real butter here and there. Remember fats are essential to a healthy, well-balanced diet!

Please reach out with questions, comments, or for further discussion.

Lindsey, PharmD, BCPS

References

Gunnars, K. (2023, June 9). Are vegetable and seed oils bad for your health?. Healthline. https://www.healthline.com/nutrition/are-vegetable-and-seed-oils-bad#bottom-line

Harnisch-Weidauer, L. (2024, January 24). What you need to know about cooking oils and cancer : Dana-Farber Cancer Institute. Dana. https://blog.dana-farber.org/insight/2023/09/what-you-need-to-know-about-cooking-oils-and-cancer/

Kunik, K. (2023, October 24). 4 healthy cooking oils (and 4 to avoid). Healthline. https://www.healthline.com/nutrition/best-cooking-oils

Veerman, J. L. (2016). Dietary fats: A new look at Old Data Challenges established wisdom. BMJ, i1512. https://doi.org/10.1136/bmj.i1512

Zelman, D. (2023, July 14). Vegetable oil: What are the health benefits?. WebMD. https://www.webmd.com/diet/health-benefits-of-vegetable-oil