15: The Truth About Seed Oils and Family Nutrition

Amid rising controversy and misinformation on social media, this episode explains what seed oils are, how they’re processed, and whether they deserve the “toxic” label they’ve been given.

As a Registered Dietitian, Sarah dives into the science behind seed oils, their role in heart health, inflammation, and whether they’re safe for kids. 

In this episode, we discuss:

• What seed oils are and how they differ from fruit oils 
• How seed oils are processed and what that even means
• The truth about linoleic acid (omega-6 fat) and inflammation
• Why omega-6 fats are misunderstood and how they compare to omega-3s
• The actual scientific evidence on seed oils and heart health
• Why seed oils can be safe — even beneficial — for kids and families
• How to store and use seed oils safely at home

Chapters

• 0:00 Understanding Seed Oils: The Basics
• 9:00 Science Behind Seed Oils
• 19:00 Seed Oils and Family Nutrition

Transcript

Sarah Schlichter (00:02.094)
Hello everyone. Today is going to be a short episode, but it's going to be jam packed with information. And I think this topic, especially in this day and age right now is top of mind for some consumers. I've received many questions about it. If you go on social media, you'll see many rants about seed oils. And let me just tell you right off the bat that not a lot of them are qualified to even be talking about seed oils.

But today we're really gonna focus on the topic of seed oils and should you be feeding them to their family, to your family? Are they as bad as social media, the media in general has made them out to be? And what's the truth? Because as with many topics in nutrition, it's never black and white. There's always a gray area. There's always things that you're not hearing. There's another side of the story.

And as a dietician, it's my responsibility to share evidence, not just my opinion. So we're going to talk about some evidence today too. So after this quick episode, hopefully you'll walk away with a better understanding of how these can fit into your diet if you want them to and just kind of what that means, their health benefits, et cetera.

So we're just going to kind of break this down into what seed oils are first and foremost, like what oils fall under the seed oils category, a little bit about the processing of how they're made, the nutrients, the fats that you'll find in them. And then we'll go over some research and we'll end with kind of just some practical tips. So again,

I don't want to make this more confusing than it needs to be, but I want to make sure that you're hearing the whole story, not just a one-sided view of seed oils because one of the things that really bothers me as a dietitian and I'm sure all dietitians would agree is when people spread misinformation on social media, especially those people without a degree, without an understanding of nutrition and it's just like they just echo each other. So let's get down to what the truth is here.

Sarah Schlichter (02:13.166)
Okay, what are seed oils? So seed oils come from seeds and the category of seed oils when we say seed oils, we're talking about canola oil, corn, cottonseed, grapeseed, soybean, sunflower, rice bran, and peanut oils. Unlike olive oil and avocado oil, those come from the fruit. So seed oils are a commonly used ingredient in many foods, salad dressings, pasta sauces, cakes, cookies,

Restaurants use them for deep frying foods and things like that. So right off the bat, we can already say that yes, seed oils may be used in some foods that are considered quote unquote unhealthy, but that doesn't mean they're, they necessarily are unhealthy. So I think we really have to differentiate causation, association from causation here. The United States seed oils,

increased in popularity in the 1960s, especially soybean oil. And from then on, there's just been a gradual shift away from animal sources of fat, like butter, lard, to more plant-based sources. And I think that kind of echoes just the general trends that people are trying to eat more plant-based sources of protein and more plants in general, which can be great.

And along with an intake in seed oils comes an intake in linoleic acid. And we're going to talk about that a lot throughout this episode. You're going to hear linoleic acid. It is an unsaturated fat, the main one that is found in seed oils. Okay. So a lot of people will say, well, seed oils are so processed. Yes, they are processed. A lot of foods are processed because

they're not always fit to consume right from the field or right in their natural state, right? We do have to make them safe. We have to make them palatable. We have to make them able to be stored, et cetera. So seed oils do undergo considerable processing. However, according to the NOVA food classification system, they are not considered ultra processed. So I have the NOVA system up right now and there's a few different levels, groups,

Sarah Schlichter (04:32.042)
if you will, when the NOVA system classifies processing, like group one, minimally processed foods. So that's things like nuts, peanuts, fresh and dried herbs, pasteurized vegetables, fruit juices with no sugars, whole grains, cereals, eggs. So things that we would think of as quote unquote healthy. Group two, oils, fat, salt and sugar. And then we go down to group four, which are what

we hear as the most ultra processed foods. And even here, let me tell you, there can be some black and white. So energy and sports drinks, breakfast cereals and bars. There's a wide variety of those on the market. So even ones with lower amounts of sugar, flavored yogurts, chocolate milk, ice cream, desserts, pastries, things like that.

So that is group four, the ultra-processed foods. And like I said, these seed oils are not classified as ultra-processed if we were according to the NOVA system. So a little bit more than you need to know about how they're processed is essentially they extract oil from the seeds using pressure or solvents like hexane.

So then a consumer might say, well, they're so processed that's harmful substances that are being added to the food or in the process that might reach consumers. And this is not true. The solvents like hexane that are used in the processing and refinement are not in the final product that reaches shelf. So it does not pose health risks to consumers.

And like I mentioned, many foods are processed. mean, baby carrots aren't grown like that. They have to be cut and packaged and processed in a way to make them safe and have a longer shelf life for consumers. So we do have a great body of evidence that indicates that seed oil consumption is not harmful. It's actually can promote overall health. I know that's not a side of the story you're used to hearing, but I don't want to get ahead of myself.

Sarah Schlichter (06:44.14)
Before we get to the research, we're still kind of talking about what they are. Now, when talking about seed oils, I do think it's important to know that you want to store them properly. So fats in general that have multiple double bonds, so we're talking about unsaturated fats, are more susceptible to becoming oxidized or just becoming exposed to oxygen during storage, more so than monounsaturated fats.

So those are fats with just one double bond like olive oil and saturated fats. And saturated fats are those that come from animals. So again, these linoleic acid, these seed oils have multiple double bonds, meaning they're more susceptible to becoming oxidized. Now that statement can be misconstrued. So that doesn't mean that they promote inflammation.

That just means we want to store them properly, store them away from light and heat. Don't keep them for years upon years. We want to purchase them in amounts that can be consumed over months rather than longer periods of time, especially if it's out on your counter, it is exposed to light or heat. That will increase the process of oxidation. But again, oxidation doesn't mean they're causing oxidative stress in humans. And this is...

Excuse me, this is because as humans, have mechanisms in place to combat that. You know, we have antioxidant systems and other things going on. So again, it's not just A plus B equals C. There is a lot of nuance here. I think the one thing that's important to know is that a lot of people use them. They're common in home cooking. They are easy to find. They last a while. They are affordable. And then again, many restaurants and places that are

doing food prep on a larger scale also do have them.

Sarah Schlichter (08:42.69)
They also have a high smoke point, which again, which is why they're used for frying deep frying foods. but they just are staples in many homes and commercial kitchens. So where did all of this controversy come from? Why do we hear words like toxic and inflammatory, all of this rhetoric? So I think a lot of it just comes from misunderstanding, misinformation, even disinformation on social media.

because the issue really is less about the seed oils themselves and perhaps more about the foods they're in combined with just a misunderstanding in general about omega-6 fatty acids.

Sarah Schlichter (09:28.782)
So I mentioned that seed oils have linoleic acid that is an omega-6 fatty acid. You may have heard of omega-6, you've probably more so heard of omega-3 fatty acids and those are anti-inflammatory. Those are very important for inflammation, for skin health, for brain health, et cetera. The main takeaway with omega-3 fatty acids is that Americans aren't getting enough of them in the diet. We're not eating enough seafood.

We're not eating, it's hard to get omega-3 fatty acids through the diet to be completely honest, especially if you're not eating seafood. So that is a big problem at play. It's easier to get omega-6 fatty acids, but somehow this information has become misconstrued.

to know that there's a huge imbalance in omega-6 and omega-3 fatty acids in the diet. And to some extent there is. Yes, we're not getting enough omega-3 fatty acids. We're probably just falling short on unsaturated fatty acids in general. And omega-3 fatty acids are anti-inflammatory, more so than omega-6 fatty acids. But that doesn't mean omega-6 fatty acids are bad.

Sarah Schlichter (10:46.71)
It doesn't mean they cause more inflammation than omega-3 fatty acids. Somewhere along the line, this has become, we have become misinformed. A lot of social media influencers have taken this and run with it. I think the bottom line here is yes, we want to eat more omega-3 fatty acids, walnuts, fatty fish. Canola oil is also high in omega-3s. And guess what? Canola oil is a seed oil. So again,

There's always gonna be some overlap in some gray areas here.

But we don't necessarily need to focus on reducing omega-6 fatty acids from our diets. Excuse me.

Sarah Schlichter (11:46.476)
Okay, so let's talk a little bit about the scientific evidence. There's actually a lot of scientific evidence on seed oils, linoleic acid, et cetera. There was actually a new peer-reviewed study that came out in March in the journal Nutrition Today, which reviewed the scientific consensus on seed oil. I'll make sure I link it in the show notes here. So if you are someone who does like to read scientific papers, this will be right up your alley.

but it talked about their favorable fatty acid composition, especially compared to saturated fats and how they do support cardiovascular health. So again, we're reiterating that there is a lot of scientific evidence that agrees that replacing saturated fat in the diet with monounsaturated and polyunsaturated fat can lower our blood cholesterol levels, particularly the LDL cholesterol, which is the

big risk factor for heart health, right? Elevated LDL cholesterol is an important risk factor for cardiovascular disease. And we have evidence that linoleic acid,

in these seed oils can reduce LDL cholesterol.

Bet you're not hearing that information. The US Food and Drug Administration, so the FDA has approved coronary heart disease health claims for seed oils, canola oil, corn oil, soybean oil, and olive oil, which again, that's not a seed oil, but as well as oils that are high in monounsaturated fat, which is what we typically hear is great for heart health. And all of this is based on their ability to lower blood

Sarah Schlichter (13:33.422)
levels, especially when we're replacing saturated fat. So if we're trying to reduce saturated fat in the diet, we're probably going to replace it with something, right? So a lot of the research shows that reducing or replacing that saturated fat with unsaturated fat, such as linoleic acid, is favorable for our heart health. And linoleic acid is the most prevalent fatty acid in soybean oil.

Again, soybean oil is the most consumed oil in North America. So this is a good thing to know. This should steer us, this should reiterate that soybean oil is health conscious. It can be used for cooking. It doesn't need to be surrounded by fear because it does have many cardiovascular benefits and as well as other functions. So we have some research.

that talks about how linoleic acid can improve glucose metabolism. It's positively associated with insulin sensitivity, right? So these are huge and can reduce the risk for developing type two diabetes. And if we're gonna go further, type two diabetes is a well-known risk factor for cardiovascular disease. So if we can reduce our risk for cardiovascular disease and also improve our insulin sensitivity, all of those are positive things.

Cough cough

Sarah Schlichter (15:11.82)
We also have several randomized control trials. So those are human intervention studies showing that there's no effect of linoleic acid on markers of oxidative stress. So that goes back to the earlier claims that...

Sarah Schlichter (15:32.78)
The earlier claims that these omega-6 fatty acids, seed oils in particular, are inflammatory. They're not. In fact, they are reducing our risk of developing several chronic diseases, inflammatory diseases, diseases like type 2 diabetes, liver disease, and even dementia. And then we have lots of independent studies that show

followed more than 200,000 adults for more than 30 years. And they found that those with the highest daily intake of plant-based oils had a 16 % lower total risk of premature death. Why could that be? Higher linoleic acid intake is also associated with a 15 % reduction in the risk of heart disease and a 21 % reduction in cardiovascular disease mortality.

So again, many clinical trials are reiterating.

Sarah Schlichter (16:36.182)
the health benefits of linoleic acid.

So is there any relationship between linoleic acid inflammation?

I went down this rabbit hole and it seems that the belief that linoleic acid does increase inflammation is due to the conversion of linoleic acid to a rock. I always had trouble saying this in biochem. Arachidonic acid. This is way more information than you need to know in this podcast, but arachidonic acid is a metabolite linked to inflammation.

So linoleic acid is converted to arachidonic acid, potentially. So in many consumers' minds, that automatically means, well, it's inflammatory. However, we have a lot of evidence that has debunked this misconception. So again, I'm just reiterating things I've already said, that it's established that linoleic acid has a negligible impact on blood or tissue levels of arachidonic acid. And the study is

consistently show that it does not increase inflammation. On the contrary, some suggest that it may decrease inflammation and improve the health outcomes that we've already talked about, namely cardiovascular disease risk. Okay, so you're hearing this and we always think about nutrition like think of it in the big picture, the dose makes the poison, right? So how much is too much? Well, we have an AMDR, which

Sarah Schlichter (18:14.38)
translates to an acceptable macronutrient distribution range. And this was established by the Institute of Medicine, which is now known as the National Academy of Medicine, blah, blah, blah. Anyway, the AMDR for linoleic acid is five to 10 % of daily energy needs. So when we talk about our fat needs, our fat needs usually are...

We're usually trying to limit limit our saturated fat to less than 10 % of our total energy intake

Sarah Schlichter (18:50.764)
And again, we want to replace it with unsaturated fats. Americans are consuming about this. Americans are actually consuming about this amount. They're consuming about 8%, which is in line with these recommendations. So that is 8 % of their daily energy intake coming from linoleic acid.

Sarah Schlichter (19:22.08)
Okay, so.

Now let's shift to talking about seed oils in kids because again, everything that we hear on social media, we're always thinking about our kids, but we have to be able to filter some of that information. So are seed oils harmful for babies, toddlers or kids? No, not in small amounts, right? Everything we've just talked about would apply to kids, but their bodies are much smaller. And I think we just have to be reasonable and practical.

So having soybean oil, having corn oil, safflower, sunflower oil in your house and cooking with it, great. Those are unsaturated fats. So if you're reducing your saturated fat intake and using those, those are great replacements. We more so want to focus about what they're eating as a whole, right? So yes, some of these seed oils can be in the ultra processed foods. They can be in the baked goods. They can be in the highly fried foods and some frozen foods.

Not to say that all of those foods don't belong in a toddler's diet because there's always room for, there's always room for different types of foods, but we do want to focus more so on the healthy foods, right? The fiber rich fruits and vegetables, limit the high sugar packaged options, limit the packaged options that are high in fats, limit the bakery items for children.

And if you're eating out, try to gravitate more towards grilled rather than fried and things like that. So seed oils are just kind of a side effect of a lot of those foods. Yes, they're in them and they're used to cook them. But if we're eating less of those foods, then we're going to be reducing our intake of seed oils anyway. So should you be completely avoiding them? No. Feed your family in a way that works for you. Again, they're affordable. have a

Sarah Schlichter (21:17.836)
long shelf life, have a neutral flavor and high smoke points. So that makes them really versatile in the kitchen. They're going to last a long time. They're easy to cook with. Again, if your family likes them and they work for you, there should be no reason that you're fearing them. Okay. So we have to look at this with a balanced perspective. Yes, you can consume more of the mono unsaturated fat. So olive oil and avocado oil,

You can also use other replacements for seed oils. If you like cooking with butter, great. But if you're looking to reduce your saturated fat content, then replacing them with unsaturated seed oils can be a great step for your health.

Sarah Schlichter (22:10.89)
If you're just pan frying some in a pan to cook your chicken or your fish, there's no health concerns like inflammation. Again, make sure you're storing them in a cool, dark place because if you're not storing them properly, they will oxidize. That doesn't mean your body is getting inflammation, but you do want to avoid oxidation because

Sarah Schlichter (22:41.834)
If the oils do oxidize, they do become rancid. So you don't want to be taking in rancid oils. So storage is important, but know that seed oils can be a part of healthy and unhealthy diets. It's always just how you're using them. So instead of cutting out all the foods with seed oils, I would just focus on eating more of the whole foods.

eating more fruit and vegetables and frozen and canned fruit and vegetables are great. Again, you can look at the ingredients on the back on the food label to know if there are any oils added, how much sugar, how much fat, et cetera. But just avoiding, you know, those shortcuts in the kitchen isn't necessary because again, we're here to feed a family. We want to reduce stress. There's so much that goes into the overall health than just exactly what's on the plate.

But if we're looking at...

If we're looking at an overall pattern of healthy eating, this is it. Seed oils can be part of that. Diversify your diet, eat different oils, include olive oil and avocado oil as well. Use different cooking oils throughout the week and you don't really have to worry too much about that. There's never one size fits all.

Different oils have different tastes and seed oils are fine for cooking. They are not harmful. And as we talked about earlier, they can actually be beneficial for many health conditions. I hope this short episode was helpful and just clarified some of the myths that you may have heard about seed oils. I hope it empowers you to cook in a way that satisfies you and makes your family.

Sarah Schlichter (24:35.16)
cooks in a way that is attainable for your family and try not to fear all of the ingredients in your kitchen. If you have any more questions about seed oils, please reach out. Again, I would really appreciate if you are enjoying this podcast, leave a review. I am going to start raffling off some fun things for reviews now that I'm getting deeper and deeper into the podcast.

And if you have any questions, there's a number in the show notes that you can actually leave me a voicemail or text. And when I get those questions, I can make sure to answer them on the show.

So until next time.

Try to reduce the stress around eating and eat what makes you happy.