Are Edible Oils Harmful or Beneficial to your Health?

 

You may be using sunflower or canola oil in your home. Whether you cook with it, add it to salads, or fry your parathas, the oils extracted from seeds are popular all worldwide.

But these oils are currently the subject of heated debate online.

 

Recently, some controversial claims have emerged about the edible oils derived from seeds, canola, and sunflower oil, which are said to have harmful effects. Is there any truth to these claims?

 

Seed oils have been the subject of countless social media posts in recent years. People claim that they are ‘toxic’ and ‘harmful to health’.

 

Critics have even coined the term “Eight Bad Oils” for certain seed oils. This refers to eight popular seed oils—canola, corn, cottonseed, grapeseed, soy, rice bran, sunflower, and cotton flower—because they are accused of causing heart disease and type 2 diabetes.

 

Are seed oils harmful to health, or is this hostility towards them unjustified?

 

Does Seed Oil have Anything to do with Heart Health?

 

Much of the recent criticism of seed oils concerns their high omega-6 fatty acid content.

 

Omega-6 fatty acids are essential, meaning we need them, but our bodies cannot produce them.

 

In recent years, some scientists have argued that omega-6s may cause chronic inflammation, which can increase the risk of diseases including heart disease and cancer.

 

“Controlled trials have shown that omega-6 fatty acids do not increase inflammation,” says Darosh Mozfarian, professor and director of the Food as Medicine Institute at Tufts University in Massachusetts, US.

 

The new study shows that omega-6 fatty acids produce unique natural molecules, such as lipoxins, that have powerful anti-inflammatory effects in the body.

 

A recent study studied the diets and health of more than 200,000 people in the US for almost 30 years.

 

Researchers found that people who consumed more vegetable oils (including seed oils) were less likely to die from heart disease or cancer during the study period. On the other hand, people who consumed more butter were more likely to die.

 

There have been several studies on how omega-6s affect our heart health, in which scientists explore the relationship between diet and health.

 

Studies rely on people’s own data about what they eat, says Matti Marklund, assistant professor of human nutrition at the Johns Hopkins Bloomberg School of Public Health in the US.

 

“This can be problematic because people can have inaccurate memories of their dietary habits, or even misrepresent them,” he adds.

 

Another way to measure omega-6 intake is to measure the average amount of individual components and components in a person’s diet.

 

However, Marklund says, “It can be difficult to measure how much people say they’ve eaten.”

 

Studies investigating the effects of omega-6 on our health have examined linoleic acid. The omega-6 fatty acid is found in high amounts in seed oils and is known to lower ‘bad’ LDL cholesterol in our blood.

 

In a 2019 study, Marklund looked at how many people developed and died from heart disease, rather than focusing on the levels of fatty acid in the blood of 30 observational study participants.

He found that those with the highest levels of linoleic acid in their blood had the lowest risk of developing heart disease.

Christopher Gardner, director of nutrition studies at the Stanford Prevention Research Center in the US, says there is some confusion about omega-6 and heart health.

This is partly because of omega-6’s role in blood clotting, which Gardner says people tend to associate with strokes and heart attacks.

Omega-3s, he says, thin the blood. “If you have a cut on your hand, you want it to clot. You have to balance it out.”

 

Meanwhile, scientists concluded in a 2019 analysis of 30 studies that people with higher levels of linoleic acid in their blood were seven percent less likely to develop heart disease.

“Linoleic acid can reduce the risk of heart disease by improving cholesterol, and it can also improve glucose metabolism which can reduce the risk of type 2 diabetes,” says Marklund.

 

Seed Oil and the 3:6 Ratio

 

Another common accusation against seed oil is that eating omega-6 compared to omega-3 is harmful.

 

In the Western world, omega-6 fatty acids account for about 15% of our total energy intake.

 

The ratio of omega-3 to omega-6 in the average person can be as high as 50:1.

 

However, according to one study, it should be 4:1 to reduce our risk of heart disease.

 

A 2022 review and meta-analysis by the World Health Organization found that a higher omega-6:3 ratio was associated with a higher risk of dementia and ulcerative colitis, a chronic inflammatory bowel disease.

 

On the other hand, a higher omega-3:6 ratio was also associated with a 26% lower risk of depression.

 

Overall, the scientists in the WHO study concluded that high intakes of omega-6 fatty acids from seed oils are unlikely to increase the risk of death or disease.

 

Some people believe that more high-quality research is needed.

 

Although some scientists say that you shouldn't get too much omega-6 compared to omega-3, Marklund says, it's better to increase your intake of omega-3 than to reduce your intake of omega-6, as both have health benefits.

 

How is Oil Extracted from Seeds?

 

The seed oils are extracted from the seeds of plants.

 

There are some concerns that seed oils are extracted with hexane, a chemical made from crude oil, but there is little evidence that this process causes harm.

 

While some evidence suggests that hexane is linked to some medical conditions after extraction, the oil is bleached and refined to remove this chemical.

 

“Scientists would say that hexane is a normal part of food processing, and deodorizing and bleaching remove potentially harmful compounds,” says Gardner.

 

Cold-pressed seed oils avoid this process because they involve squeezing the seeds to extract the oil. But the resulting products are more expensive.

 

Can Seed Oil Promote Tumor Growth?

 

Despite a wealth of research showing the potential health benefits of omega-6s, researchers have recently found that this fatty acid may promote the growth of a specific type of breast cancer.

 

The findings could also have implications for the effects of omega-6s on other diseases.

 

Until now there has been limited research looking at the role of omega-6 fatty acids, Cancer cells use nutrients as fuel for their growth.

 

A study published in March this year found that an omega-6 fatty acid called linoleic acid helped cancer cells grow and multiply in patients with triple-negative breast cancer (TNBC).

 

This is the most aggressive subtype of breast cancer and is not particularly affected by targeted therapies.

 

Nikolaos Kondouros, a postdoctoral associate at the Weill Cornell Medicine Research Center in New York, says that past studies have shown no association with omega-6 fatty acids, or a small increase in risk.

 

He says those studies don’t take into account that there are many subtypes of breast cancer. They all differ in terms of patient survival and prognosis and how they might respond to targeted therapy.

 

Kondouros says that TNBC responds most to omega-6 linoleic acid.

Working with a team of researchers, Kondouros discovered in the lab that when fed omega-6, TNBC cells activate a protein complex that drives tumor growth and progression.

 

Another protein is found in higher amounts in TNBC tumors than in other breast cancer subtypes and is known to transport fatty acids and lipids throughout the body and inside cells to exactly where they should be.

 

Kondoros says, along with omega-6s, these proteins may also be relevant in other chronic diseases, such as obesity and type 2 diabetes.

 

The research could potentially shed light on treatments for TNBC patients, but it doesn’t necessarily have broader implications for everyone.

 

“It’s important to remember that omega-6 fats are essential. If you cut them out completely, they can have adverse effects on your health,” Kondoros says.

 

Which Seed Oil is Healthier?

 

Seed oils, such as canola and soybean oil, have been studied more than others. So there is more evidence supporting them.

 

Mozaffarian says, “Each of these provides a balanced blend of healthy fats, including monounsaturated fats, omega-6 polyunsaturated fats, and omega-3 polyunsaturated fats”.

 

He added that canola oil has similar anti-inflammatory effects and improves blood cholesterol levels compared to olive oil, which has long been considered the healthiest.

 

A meta-analysis of twenty-seven trials found that canola oil significantly reduced LDL cholesterol compared to sunflower oil and saturated fat. Another found that it dramatically reduced body weight, especially in people with type 2 diabetes.

 

Canola oil helps improve blood cholesterol levels and also modestly reduces body weight.

 

The canola oils’ healthy fats, especially omega-6 polyunsaturated fats, also improve blood glucose, insulin resistance, and insulin production.

 

Soybean oil also improves cholesterol levels compared to saturated fats.

 

A study found that people who ate more soybean oil had a lower risk of death from all causes.

 

“Seeds are one of nature’s most nutritious gifts,” says Mozfarin. “They’re a package of beneficial, healthy fats.”

 

This backlash against one of the most studied foods in nutritional science has been puzzling to some scientists.

 

But Mozfarin says the misconception may be due to “a mishmash of partial truths.”

 

For example, some people may associate seed oil with ultra-processed foods (UPFs), which often contain seed oils, especially canola, corn, soybean, and sunflower oils.

 

In recent years, there has been a lot of attention paid to the health risks of consuming too much UPF, including an increased risk of type 2 diabetes and heart disease.

 

“But these risks also come from the high starch, sugar, salt content, and hundreds of artificial ingredients,” says Mozfarin.

 

In recent years, some people have also linked the increased consumption of seed oils to the rise in obesity and diabetes.

 

“If you want to compare people eating more seed oils and the unhealthy outcomes, it’s because we’re eating a diet high in sugar and sodium,” says Gardner.

 

“I wouldn’t like to see people give up seed oils because of this seed oil war,” says Gardner.

 

While some scientists are calling for more rigorous research into the effects of seed oil consumption on our health, Marklund and others say there are already many good-quality trials showing benefits on blood cholesterol, blood glucose, and insulin levels in the general population.

For more Interesting Articles click the Link: Health Care