Are seed oils really bad for you?

Seed oils like canola and sunflower oil have attracted controversial affirmations to the harmful effects lately. Is there any real for them?

You could have a bottle of sunflower oil or canola oil (rapeseed) hidden somewhere in a kitchen cupboard. Whether you cook with them or sprinkle them on salads, seed oils are popular around the world.

But these unpretentious seed oils have become the center of an online heated debate.

In recent years, seed oils have become the target of countless publications on social networks, people saying that they are “toxic”, “toxic” and, ultimately, damage our health. Critics have nicknamed Some seed oils “The Hateful Eight” – Referring to eight popular oils, canola, corn, cotton seeds, grape seeds, soybeans, rice sound, sunflower and Samedlower – and blame them for provoking a heart disease and type 2 diabetes.

Is seed oils really the enemy, or antagonism towards them is unjustified?

A large part of recent criticisms of seed oils focus on their high content of omega-6 fatty acids.

Recent research studied the diet and health of more than 200,000 people in the United States for about 30 years. Researchers have found that people who consumed more vegetable oils (including seed oils) were less likely to die from cardiovascular disease or cancer during the study. On the other hand, those who have higher butter consumption were more likely to die during the same period.

There are many observation studies on how Omega 6 affect our heart health – where scientists examine food and health data, and find associations between the two.

But some observation studies are based on people’s own accounts of what they eat, explains Matti Marklund, assistant professor of human nutrition at the Johns Hopkins Bloomberg School of Public Health in the United States. And that, he adds, can be problematic because people can be informed, or even be dishonest, about their eating habits.

Another way to measure omega 6 intake is to measure the average quantity in individual components and ingredients in a person’s diet. However, adds Marklund, it can be difficult to translate what people say they have eaten in certain quantities.

In a 2019 study, Marklund rather focused on blood acid levels in the blood Participants in around 30 observation studies – some who followed people up to 30 years old – and examined the number of cardiovascular disease developed and died. He found that those with the highest levels of blood linoleic acid had the lowest risk of developing cardiovascular disease.

There is a certain confusion concerning Omega 6 and Heart Health, explains Christopher Gardner, director of nutrition studies at the Stanford Prevention Research Center in the United States.

This follows in part from the role of Omega 6 in the blood coagulation process, that Gardner says that people wrongly associate with stroke and heart attacks. Omega 3, he says, tends to be more asking for blood. “If you had a hand injury, you would like her to safe,” he said. “You need balance.”

“Linoleic (acid) could improve cholesterol to reduce the risk of cardiovascular disease, and also improve glucose metabolism, which reduces the risk of type 2 diabetes,” says Marklund.

Another current accusation leveled in seed oils is that eating too much omega 6 compared to omega 3 is harmful.

A World Health Organization 2022 examination and meta-analysis reported that an Omega 6: 3 higher report was associated with a greater risk of cognitive decline and ulcerative colitis, a chronic inflammatory disease of the intestine.

On the other hand, an Omega 3: 6 higher report was also linked to a reduced risk of 26% depression. Overall, scientists involved in the WHO study have concluded that high consumption of omega 6 fatty acids of seed oils should not increase your risk of death and disease – but states that more high quality research is necessary.

But while some scientists argue that you should not have too much omega 6 compared to omega 3, Marklund says that it is better to increase your contribution from omega 3 rather than consuming less omega 6, because both are associated with health benefits.

Unlike other oils, seed oils are extracted from plant seeds. There are concerns that Seed oils are extracted from hexane – A chemical made from crude oil – but there has been little evidence so far, which suggests that this process can cause problems.

“Scientists will say that hexane extract is normal in the transformation of food, and deodorization and whitening eliminates potentially harmful compounds,” explains Gardner.

Cold pressed seed oils Avoid this process entirely, because it involves tightening the seeds to extract the oil – but this results in a more expensive product.

Despite an abundance of research showing the potential advantages that Omega 6 could have for our health, researchers have recently discovered that this fatty acid can fuel the growth of a specific type of breast cancer. TThe results may have implications on the impact of Consumption of omega 6 on other diseases.

Previous studies suggest that there is no association with omega 6 fatty acids, or a small increase in risk, explains Nikolaos Koundouros, postdoctoral partner with Weill Cornell Medicine Research Center in New York. But these studies, he says, did not take into account that there are several subtypes of breast cancer, and that they all differ in terms of survival and prognosis of a patient, and how they could react to targeted therapy.

The TNBC seems to react most to omega 6 linoleic acid, known as Koundouros.

In addition to a team of researchers, Koundouros discovered in the laboratory which, when nourished by Omega 6, TNBC cells activate a protein complex linked to tumor growth and progression. Another protein, which is in larger quantities in TNBC tumors compared to other subtypes of breast cancer, is known to have fatty acids and lipids throughout the body and inside cells exactly where they must be.

Koundouros explains that these proteins, as well as omega 6, can also be relevant in other chronic diseases, such as obesity and type 2 diabetes.

This research could potentially shed light on treatment options for TNBC patients, but it does not necessarily have wider implications for everyone, says Koundouros. “It is important to remember omega 6 fats are essential for a reason; if you cut them completely, you may have harmful side effects,” he said.

Some seed oils – such as canola oil and soy oil – have been studied more than others, so have a more rigorous evidence.

“These each provide a balanced combination of healthy fats, including monounsaturated fats, omega-6 polyunsaturated fats and omega-3 polyunsaturated fats”, explains Mozaffarian.

“Canola oil produces excellent advantages for blood cholesterol levels and also modestly reduces body weight. Healthy fats in canola oil, in particular polyunsaturated fats from omega 6, also improve blood sugar, insulin resistance and insulin production,” explains Mozaffarian.

“Seeds are one of the most nourishing gifts in nature; a set of healthy healthy fats,” said Mozaffarian.

That something so well studied in nutritional science had such a reaction was a source of confusion for certain scientists. But this misunderstanding can come from a “displaced combination of partial truths”, says Mozaffarian.

“But these dangers arise from too much starch, sugar and salt, loss of natural intact structure and dozens, even hundreds of artificial additives,” explains Mozaffarian.

“But if you want to draw parallels with people who eat more seed oils and unhealthy results, it is because we eat foods that tend to contain a lot of sugar and sodium,” suggests Gardner. He says there are many ways to consume seed oils at home that do not imply UPF, as with a salad or a sautéed.

“I would hate seeing people throw seed oils because of this war of seed oil,” said Gardner.

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