New research found linoleic acid, the main fat in seed oils, is linked to a lower risk of heart disease and diabetes biomarkers

Worried About Seed Oils? Studies Say Linoleic Acid May Actually Lower Disease Risk Here's why seed oils get a bad rap, and what the science actually says

• New research suggests that linoleic acid, the main fatty acid in seed oils, can lower the risk of heart disease and diabetes.
• The findings challenge recent claims that seed oils cause chronic disease or inflammation.
• Experts say it’s the processed or fried foods cooked in seed oils that can be harmful—seed oils themselves can benefit health.

Linoleic acid—the main fatty acid found in seed oils—could potentially cut your risk of developing heart disease and type 2 diabetes, according to new research.

The findings stem from a pair of studies presented at the American Society for Nutrition’s annual meeting, held from May 31 to June 3. They haven’t yet been peer-reviewed.

The health effects of seed oils are a hot topic of debate right now, particularly after U.S. Secretary of Health and Human Services Robert F. Kennedy Jr. claimed last fall that seed oils contribute to inflammation and chronic illnesses.

“Despite growing concern by the public that seed oils are health-harming, this study adds to the already sizable body of research that says this is just not true,” said Nate Wood, MD, a Yale Medicine obesity and internal medicine physician and chef who focuses on culinary medicine.

What Is Linoleic Acid?

Linoleic acid is an essential nutrient that’s found in vegetable and seed oils, nuts, seeds, meats, and eggs. It’s a polyunsaturated fatty acid (PUFA)—a healthy fat—and is the most commonly consumed PUFA in the human diet.

PUFAs are known for offering a range of health benefits, including lowering so-called “bad” low-density lipoprotein (LDL) cholesterol levels and controlling blood sugar.

So why is this popular healthy fat suddenly so controversial? It dates back to 1969, when soybean oil—which is packed with linoleic acid—became a common additive used in processed foods, and linoleic acid intake rose dramatically.

Around the same time, obesity and diabetes prevalence started to increase in the U.S. Scientists aren’t entirely sure what’s behind this trend, but changes in chronic disease levels usually connect back to physical activity, smoking status, diet, and alcohol consumption.

Some people, including RFK Jr., say the rise in seed oil consumption and the increasing prevalence of obesity and diabetes are connected. Claims circulating in recent months center on the idea that omega-6 fatty acids in seed oils break down into harmful substances when they’re heated, leading to inflammation and chronic disease.

Consuming More Linoleic Acid Linked to Better Health Markers

This new research—along with many others—found the opposite to be true.

The researchers evaluated the health data of 1,894 people and, using data sourced from blood testing, looked at whether inflammation and blood sugar biomarkers were at all related to the amount of linoleic acid each person was consuming.

The team found that higher levels of omega-6 and linoleic acid were linked to lower levels of:

• glucose
• insulin
  
• HOMA-IR, a biomarker of insulin resistance
• inflammation biomarkers

This means participants who consumed a higher amount of linoleic acid also had a lower chance of having risk factors for type 2 diabetes and heart disease.

According to the researchers, the findings are in line with pre-existing scientific literature that links a higher intake of linoleic acid to a lower risk of diabetes, stroke, or heart attack.

“I hope that this study and others like it quash some of the fears that people have about seed oils,” Wood told Health.

Why Might Healthy Fats Provide Protection Against Cardiometabolic Diseases?

The results of this research don’t support the idea that seed oils are inflammatory.

“In fact, they are more consistent with the opposite possibility,” the study’s presenting author Kevin Maki, PhD, adjunct professor at the Indiana University School of Public Health-Bloomington and founder of Midwest Biomedical Research, told Health. “They may have anti-inflammatory effects.”

That said, it’s unclear why linoleic acid may have this effect on our metabolic health. According to Wood, seed oils may simply be a healthier alternative as compared to other common ingredients in the American diet.

Research shows, for example, that people can cut their risk of heart disease by swapping saturated fats (think: animal fats, coconut oil, or palm oil) for unsaturated fats (seed oil and vegetable oil).

According to Maki, evidence suggests fatty acids—such as the ones found in seed oils—play a role in proper cell and enzyme function. PUFAs have been shown to play a role in the regulation of the immune system and produce both pro-inflammatory and anti-inflammatory molecules.

Other research suggests that omega-3 fatty acids, similar to linoleic acid, can influence gene expression, thereby affecting fat metabolism, insulin sensitivity, and oxidative stress.

However, more studies are needed to better understand the mechanism behind how seed oils and PUFAs are affecting our metabolic health.

Is It Safe to Consume Seed Oils?

It’s true that “there have been many claims, mainly by social media influencers, about seed oils and suggestions of harmful effects relating to promoting inflammation, oxidative stress, and weight gain,” Maki said.

However, these assertions contradict the available scientific evidence that consistently shows higher linoleic acid intake benefits these metrics, he explained.

That being said, even though linoleic acid isn’t inherently harmful, be mindful of where these PUFAs are coming from in your diet, advised Nyree Dardarian, RDN, LDN, director of the Center for Nutrition and Performance at Drexel University.

“The problem isn’t linoleic acid, it’s the foods that contain [it],” she told Health.

Fried foods and ultra-processed snacks are very often packed with omega-6 fatty acids, including linoleic acid. But “when linoleic acid comes from whole foods like nuts, seeds, and soy, it’s not only safe, it’s beneficial,” Dardarian said.

Essentially, “roasting vegetables in a seed oil is very different from eating processed chips fried in the same oil,” she added.

When it comes to ingesting seed oils, Dardarian advised:

• Using canola, sunflower, or soybean oil (in moderation) when cooking
• Diversifying your fat intake by incorporating olive oil, avocados, seeds, nuts, and butter into your diet
• Focusing on how your food is prepared overall
  

The main takeaway? You don’t need to avoid seed oils. Take it from Wood—as a culinary medicine doctor, he relies on canola oil (which is a seed oil) in his own cooking at home. “If I thought it was harmful, I wouldn’t be doing it myself,” he said.

Edited by Health, where she edits and publishes news articles on trending health and wellness topics. Her work has been featured in The Heights, an independent student newspaper at Boston College, and Minnesota Monthly." tabindex="0" data-inline-tooltip="true"> Julia Landwehr Julia Landwehr Julia is the associate news editor for Health, where she edits and publishes news articles on trending health and wellness topics. Her work has been featured in The Heights, an independent student newspaper at Boston College, and Minnesota Monthly. learn more Read more:

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This story originally appeared on: Health News - Author:Julia Ries