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Headlines in different publications claim that GM soybean oil is “healthier” and “equally unhealthy” compared with non-GM soybean oil. Who is right? Claire Robinson reports

How to make sense of the conflicting headlines on a mouse feeding trial with GM and non-GM soybean oil? The first article (item 1 below), from a Bangladesh newspaper, is titled, “Genetically modified soybean oil equally 'unhealthy’”, while the second (item 2), from Science 2.0, is titled, “GMO soybean oil is healthier than organic or conventional”.

Which is correct? While the study doesn’t seem to have been published yet, an analysis of the information available in the media suggests that neither headline is accurate.  

The mouse feeding study tested a diet rich in oil made from DuPont Pioneer’s Plenish GM soybeans, against a diet containing non-GM soybean oil, a diet containing coconut oil, and a low-fat diet.

Plenish soybeans are engineered to produce higher levels of oleic acid and low levels of linoleic acid – a similar profile to olive oil. A diet rich in oleic acid, obtained from olive oil, has been found to reduce so-called bad cholesterol. DuPont Pioneer claims Plenish is “heart-healthy”.

However, these claims are cast into doubt by the new study. The researchers found that a diet containing GM soybean oil induced weight gain and fatty liver essentially identical to that of a diet with regular soybean oil. Excess weight and fatty liver are both known risk factors for heart disease.

The only way in which the GM oil-fed mice could be called healthier than the non-GM oil-fed mice is that they remained insulin sensitive and had somewhat less fat tissue. The maintenance of insulin sensitivity in the GM soybean oil-fed animals suggests that GM soybean oil might be less likely than conventional soybean oil to lead to diabetes.

So Science 2.0’s claim that “GMO soybean oil is healthier than organic or conventional” is true of two parameters measured over a relatively short timespan: insulin resistance and the amount of fat tissue. And the experiment appears not to have tested organic oil at all. So the Science 2.0 headline, “GMO soybean oil is healthier than organic or conventional”, is incorrect in that respect.

Is the take-home message of this study to eat GM soybean oil if you want to avoid diabetes and weight gain? No. Both GM and non-GM soybean oil diets were found to be less healthy than a coconut oil (a saturated fat) diet. Mice fed the GM and non-GM soybean oil diets had worse fatty liver, glucose intolerance and obesity than the group that got all their fat from coconut oil.

It remains to be seen whether the developer company Pioneer will be forced to withdraw claims that Plenish is “heart-healthy” and has a “healthier oil profile”.

Misleading claim on substantial equivalence

The Science 2.0 authors incorrectly claim in their article that “GMO soybean oil is identical to soybean oil made from a conventional or an organic soybean”. Compositionally, that’s untrue. An analysis by Bøhn et al of GM, conventional, and organic soybeans from Iowa found that “Using 35 different nutritional and elemental variables to characterise each soy sample, we were able to discriminate GM, non-GM conventional and organic soybeans without exception”, demonstrating that they were substantially NON-equivalent.

One of those 35 variables was the presence in the GM soybeans of residues of the weedkiller glyphosate, which GM soy is engineered to tolerate, and its still-toxic breakdown product AMPA. Glyphosate and AMPA were found in the GM soybeans but not in the non-GM conventional or organic soybeans.

Finally, it’s worth noting that the mouse feeding study tested the GM soybean oil diet for only 24 weeks – half the duration needed to qualify as long-term and a quarter of the duration needed to test for cancer effects. So we don’t know if the GM oil is safe to eat over the long term. That’s a pity, since one study linked high oleic acid levels in red blood cells with an increased risk of breast cancer. Other studies support a decreased risk of cancer.

Susan Knowlton, a Senior Research Manager with DuPont and leader of the DuPont Healthy Oils team, has conceded that “the jury is still out” on the cancer effects of oleic acid. And she doesn’t appear interested in finding out, as she added, “We are not working in this area ourselves.”

So is GM soybean oil healthier than non-GM? The answer, based on this study, is that it depends what you are looking at. It might involve less risk of diabetes, but it’s just as likely as non-GM soybean oil to make you and your liver fat. As for long-term health effects, no one knows. In short, it’s best to stick to coconut and olive oil.

1. Genetically modified soybean oil equally 'unhealthy'
2. GMO soybean oil is healthier than organic or conventional

1. Genetically modified soybean oil equally 'unhealthy'

IANS/bdnews24.com, 8 Mar 2015
http://bdnews24.com/lifestyle/2015/03/08/genetically-modified-soybean-oil-equally-unhealthy

If you thought that genetically modified (GM) soybean oil is any better than the normal soybean oil, you might be disappointed.

A study on mice by an Indian American researcher shows that genetically modified (GM) soybean oil is as unhealthy as conventional soybean oil. The study found that GM soybean oil too induces obesity, diabetes and fatty liver.

"The GM soybean oil has zero grams trans fat and more of the monounsaturated fats that are considered heart healthy," said lead researcher Poonamjot Deol of the University of California-Riverside.

"But it had not been tested for long term metabolic effects until our current study," Deol noted.

GM soybean oil, however, does not cause insulin resistance - the inability to efficiently use the hormone insulin.

The researchers compared the effects of both oils in experiments done in the lab on mice. Four groups of mice, each group comprising 12 mice, were given different diets for 24 weeks.

The control group received a low-fat diet (5 percent of daily calories from fat), while the other groups received a diet with 40 percent of daily calories from fat.

The fourth group had 41 percent of the saturated fat replaced with the GM soybean oil.

The mice fed a diet with either of the soybean oils had worse fatty liver, glucose intolerance and obesity than the group that got all their fat from coconut oil.

But the mice whose diet included the GM soybean oil had less fat tissue than the animals that ingested regular soybean oil.

"These results indicate that linoleic acid may contribute to insulin resistance and adiposity but that another as yet unidentified component of the soybean oil affects the liver and overall weight gain," Deol pointed out.

The study was presented at Endocrine Society's 97th annual meeting in San Diego.

2. GMO soybean oil is healthier than organic or conventional

by News Staff
Science 2.0, 5 Mar 2015
http://www.science20.com/news_articles/gmo_soybean_oil_is_healthier_than_organic_or_conventional-153798

Soybean oil accounts for more than 90 percent of all the seed oil production in the United States and genetically modified (GM) soybean oil, obviously made from seeds of GM soybean plants, was recently introduced into the food supply with the benefit that it is healthier than conventional soybean oil.

Is it true?

It is true, at least in the way all food marketing, including conventional and organic, is done. Soybean oil is actually unhealthy and GMO soybean oil is identical to soybean oil made from a conventional or an organic soybean - overused, it leads to obesity, diabetes and fatty liver - but GMO soybean oil is superior in that it does not cause insulin resistance, the inability to efficiently use the hormone insulin. Vegetable oils were once thought to be the healthy alternative to animal fat, and were hydrogenated to increase their shelf-life and temperature stability. The hydrogenation, however, generated trans fats - which then became implicated in various health problems. Soybean oil is the most common vegetable oil used in the United States and it contains about 55 percent linoleic acid, a polyunsaturated fat.

"Our previous results on mice showed that replacing some of the fat in a diet high in saturated fats from coconut oil with soybean oil - to achieve a level common in the American diet - causes significantly more weight gain, adiposity, diabetes and insulin resistance than in mice fed just the high-fat coconut oil diet," said senior investigator Frances Sladek, a professor of cell biology and neuroscience at UC Riverside.

To determine whether linoleic acid was responsible for the metabolic effects of soybean oil, the researchers designed a parallel diet in which regular soybean oil was replaced, on a per gram basis, with GM soybean oil. The GM soybean oil has a fatty acid composition (low linoleic acid) similar to that of olive oil. The GM plants were developed by DuPont to reduce trans fat production, increase soybean oil shelf life and create a generally healthier cooking oil.

"The GM soybean oil has 0 grams trans fat and more of the monounsaturated fats that are considered heart healthy," Deol said. "But it had not been tested for long term metabolic effects until our current study."

Deol and the rest of the research team found to their surprise that the parallel diet containing GM soybean oil induced weight gain and fatty liver essentially identical to that of a diet with regular soybean oil, with the exception that the mice remained insulin sensitive and had somewhat less adipose (fat) tissue.

"These results indicate that linoleic acid may contribute to insulin resistance and adiposity but that another as yet unidentified component of the soybean oil affects the liver and overall weight gain," said Poonamjot Deol, an assistant in the Sladek lab.

In their experiments, the researchers gave four groups of mice different diets for 24 weeks. Each group was comprised of 12 mice. The control group received a low-fat diet (5 percent of daily calories from fat). The other groups received a diet with 40 percent of daily calories from fat, an amount common in the American diet. One diet was high in saturated fat from coconut oil, and one had 41 percent of the saturated fat replaced with regular soybean oil. The fourth group had 41 percent of the saturated fat replaced with the GM soybean oil. The body weights, food intake, glucose tolerance and insulin sensitivity of all the mice were tracked.

What the researchers found was that mice fed a diet with either of the soybean oils had worse fatty liver, glucose intolerance and obesity than the group that got all their fat from coconut oil. But the mice whose diet included the GM soybean oil had less fat tissue than the animals that ingested regular soybean oil. These mice weighed about 30 percent more than the controls that ate a low-fat diet, while the group on the diet containing regular soybean oil weighed 38 percent more than controls. The mice on the diet that was primarily coconut oil weighed only about 13 percent more than controls. Unlike the diet with regular soybean oil, the diet with the new GM soybean oil did not lead to insulin resistance.

The take home message: GMO soybean oil is better than regular or organic soybean oil, but use olive oil instead. However, olive oil is one of the more corrupt businesses around and has been for ages, so make sure the olive oil you are buying is actually olive oil.

Sladek and Deol were joined in the research by Jane R. Evans, Antonia Rizo and Cynthia Perez at UCR; and Johannes Fahrmann, Dimitry Grapov, Jun Yang and Oliver Fiehn at UC Davis who performed extensive analysis on the liver and blood samples from these mice. The results will be presented tomorrow, March 6th, at the Endocrine Society's 97th annual meeting, currently taking place in San Diego, Calif., by Deol. The research was supported by a UCR Collaborative Seed Grant as well as grants from the UCR Agricultural Experiment Station, and the UC Davis West Coast Metabolomics Center, funded by the National Institutes of Health. Deol was supported by a training grant from the National Institute of Environmental Health Sciences.