452: Are Seed Oils Harmful To Your Health?

The consumption of industrial seed oils represents a new change for human beings as they have only been recently introduced into our diet. They’re not foods that our ancient ancestors ate as modern processing methods didn’t exist then.

Is that necessarily a bad thing?

But, if you’ve spent more than 2 minutes on social media, you’ve probably seen people warning everyone about the dangers of seed oils. And because the seed oil thing is one of the more complicated and confusing arguments for people to interpret, it’s easy to just take a nutrition influencer’s word for it.

So, to prevent you from becoming one of the many misinformed people, I’m here to break it all down for you. That way you can decide if you want to eat them or not.

This article looks at the evidence to determine if cooking with these types of oils is bad for your long-term health or if it could instead help prevent heart disease by decreasing inflammation in cells?

Today we’re going to get into the claims made about seed oils and what the latest research says about them.

What are seed oils?

The term ‘seed oils’ is the term nutrition influencers on social media use to refer to oils that come from seeds. The most common ones are canola and safflower and vegetable oils, such as corn and soybean.

One of the biggest arguments against seed oils is that they’re generally extracted from plants using a chemical solvent. Then there deodorized and refined to neutralize odors and taste.

You may have also seen certain oils advertised as “cold-pressed” to let you know that the company selling the product extracted the oil by crushing the seeds from plants instead of chemicals.

But does the extraction method really make a difference to our health when we use these oils to make salad dressing and cook our food? That’s the question. A lot of things that sound terrible can turn out not to be a big deal. The microwave is one example that comes to mind. We’ll answer this question today.

You may have also heard that seed oils contain high amounts of PUFAs (polyunsaturated fatty acids) and that PUFAs are bad for your health. You may have heard doctors like Mark Hyman, influencers like Food Babe say that PUFA oils contain toxic chemicals and GMOs that should never be eaten. There’s also a pharmacist name James DiNicolantonio who rails against seed oils and PUFAs too.

One quick but important point is that all oils are a combination of monounsaturated, polyunsaturated and saturated fatty acids. (Fact: No, olive oil isn’t pure monounsaturated fat). That said, seed and vegetable oils tend to have high levels of polyunsaturated fats. So does this matter? We’ll answer this question too.

So, let’s get into answering all the questions we just talked about and more.

Does the processing of seed oils cause health problems?

First, I want to tell you that I used to be deep into the “chemicals are killing you!” line of thinking. After 23 years later into my journey as a health & fitness expert, my views have become more nuanced.

Let’s start out by saying that “yes,” there are chemicals such as hexane used in the oil refining process. And yes, the finished product that you buy off the shelf does contain some small amount of those chemicals. By small, we’re talking small. For example, canola oil has 0.8 parts per million per kilogram of fat.

So does this matter? The answer is we’re not sure. But 0.8 parts per million per kilogram of oil is not an amount that will move the needle much if it does have adverse effects on your health. Nor should you expect to feel a difference if you remove them from your diet.

If you’re concerned about using chemicals in seed oils, you can always just buy the cold-pressed version. They’re more expensive but if you’re not going to feel it financially, then go for it. However, if you’re on a budget, then I wouldn’t spend the extra money.

Do seed oils cause inflammation?

Before we answer this question, I want to tell you that I believed that omega-6 fatty acids caused inflammation. I was Paleo before it was even a term.

One of the main arguments for eating a paleo-style diet was that our hunter-gatherer diet had less omega-6s and more omega-3s (which is true) and that this imbalance has led to higher levels of disease and inflammation for modern humans.

Since then, I’ve updated my stance.

There seemed to be good evidence for this argument. But after looking at the more recent studies and having conversations with guys like Alan Aragon and others, it appears that the link between omega-6s and poor health is not as solid as once thought.

More recent research done on humans, not in rodents or Petri dishes, hasn’t found a strong link between the two.

I will say that it’s true that PUFAs are more commonly used in ultra-processed foods and that we’re eating more ultra-processed food than ever before. And it’s also actual certain chronic diseases have risen in tandem with our PUFA/ultra-processed food consumption.

In fact, more than two-thirds of all deaths are caused by one or more of these five chronic diseases: heart disease, cancer, stroke, chronic obstructive pulmonary disease, and diabetes.

Additional statistics are pretty stark: chronic diseases are responsible for seven out of 10 deaths in the U.S., killing more than 1.7 million Americans each year; and more than 75% of the $2 trillion spent on public and private healthcare in 2005 went toward chronic diseases

But are PUFAs responsible for the inflammation that’s causing these diseases, or is it something else?

Here’s what we know. Cells involved in the inflammatory process have high levels of a PUFA named arachidonic acid in them. This has led some people to speculate that eating more PUFAs in your diet will lead to higher arachidonic acid levels and, therefore, more inflammation. But a link between PUFAs and inflammation has never been proven.

In fact, a review of 30 RCTs published in 2017 found no connection between a diet high in PUFAs and inflammatory markers.

In 2019, a review of 30 cohort studies found that high levels of a PUFA called linoleic acid were assessed to reduce heart disease.

Another review done in 2020 really squashed the idea that omega-6s/PUFAs cause inflammation and/or disease. Check out this quote from the study:

“The reason that the omega-6 to omega-3 PUFA ratio seems unimportant in predicting cardiometabolic disease or inflammation is probably that concerns about this ratio are partly formed based on several incorrect and simplified assumptions—for example, that omega-6 PUFAs overall are proinflammatory, that omega-6 PUFAs (and linoleic acid in particular) have adverse effects on cardiovascular disease risk (although in fact omega-6 and omega-3 PUFAs are related to lower risk), and that reducing linoleic acid intake will lower arachidonic acid concentrations (by contrast, linoleic acid supplements do not increase arachidonic acid concentrations in plasma or adipose tissue).”

Seems clear-cut that PUFAs and omega-6s don’t pose any problem to our health, tight? Well, unfortunately, there’s a lot of nuance and unknowns when it comes to nutrition.

In the case of seed oils, a study done in early 2020 emphasizes how eating enough omega-3s, particularly DHA and EPA, is essential because of their anti-inflammatory properties. So, this This study suggests that a diet that is low in omega-3s isn’t good for inflammation levels and, therefore, health. And since we have a limited number of calories that we can eat every day without gaining extra fat, getting your fat exclusively from omega-6s isn’t a good idea.

You might be wondering what’s this all mean for seed oils and whether or not they’re good or bad for your health.

No research has ever isolated seed oils as THE cause of any disease or a direct relationship with inflammation levels. That said, it’s my opinion that the real issue is eating too many calories from ultra-processed foods is a bad thing, but using them to cook with or for things like salad dressing isn’t going to negatively affect your health. But in case you still want, please make sure you get your omega-3s in too.

As a quick side note, most of these organizations recommend a minimum of 250–500 mg combined EPA and DHA each day for healthy adults. That’s usually around 3 grams or so of fish oil per day if you take a supplement. Make sure you read the supplement label to determine the EPA and DHA dose you’re getting. Or, if you want to get it from fish, eat at least 8 ounces of omega–3-rich fish a week.

Does cooking oils at high heat damage your health?

This is a question that’s taken me years to figure out. Cooking with oils isn’t necessarily a bad thing. This depends on a few things, though.

For example, how often do you fry your food? Do you see or smell smoke from the dish you’re cooking? Do you reuse your oils?

We know that cooking oils to their “smoke points” can form some compounds that might be harmful to your health. Interestingly enough, seed oils have the highest smoke point of commonly used cooking oils. If you avoid cooking seed oils to their smoke point and throw them out after using them, you should be fine. And, of course, don’t make fried food a staple of your diet.

Are seed oils bad because they’re genetically modified (GMO)?

I’ll squeeze this on in because it’s quick. I used to be firmly against GMOs and went down quite a rabbit hole with this in my late teens and early 20s. That was then, and this is now. While I wouldn’t go out of my way to buy genetically modified food, after years of research, there’s never been any credible research showing GMOs being harmful to our health.

I also want to add that while I no longer worry about GMOs and think people that still talk about them like we did two decades ago aren’t worth listening to, I am glad that there are people out there who raise these questions. I view it as part of the checks and balances. The extremes help balance out each other. But try not to end up there yourself, haha.

At this point, you may be wondering, “Well, what oils am I supposed to cook with? Which are the best ones?”

I’ll start off by saying we just don’t know enough yet. Many factors, including your genes, will affect how your body metabolizes different oils.

So, the best advice I can give you is to use different types of oils. And only use the smallest amount you need to cook with. Why? Because of the calories.

One of the common mistakes I see my clients making when I check their nutrition diary is adding a lot of added oils. Too many calories from oil will make you fat, folks.

If you want to know the single best oil to cook with and use on salads, extra-virgin olive oil (EVOO) is the winner as far as the research is concerned. That said, I still wouldn’t add unnecessary amounts to the food I’m eating as I did in the past. More oil, regardless of what type, is more calories. And let’s not forget that all oil is processed. It’s better to eat whole food instead of the processed oil.

Conclusion

So, what do you do with all this new info?

Here are the three steps that I recommend you take action today if you want to build a leaner, fitter, and healthier body.

Step #1: What are your goals? Knowing what you want to accomplish can help you focus on what’s important and what to ignore.
Step #2: Trying to lose fat? Then pay attention to calories and protein. Don’t worry about anything else. Listen to episode 445: The Most Effective Diet For Weight Loss with Ted Ryce
Step #3: Optimizing your food choices because you’re already at a healthy body fat percentage? Then pay attention to getting your omega-3s, and don’t worry about the omega-6s so much. Also, reduce fried food in your diet and throw away oil after using it.

Finally, as I mentioned earlier, be sure to incorporate plenty of healthy fats from whole foods into your diet. Nuts, avocado, coconut, and fatty fish are excellent sources of healthy fats and can be incorporated into your diet in countless ways.

If optimal health is your goal, minimizing calories from added oils is just as crucial as reducing added sugars in your diet.