Does palm oil cause cancer?
•Natural products stop disease while processed versions encourage spread
Does palm oil cause cancer? The verdict, according to available scientific evidence, is no; cooked or boiled locally produced fresh palm oil is replete with vitamin A, good for the heart and suppresses the growth of human breast cancer cells. Palm oil from freshly squeezed fruits and processed at controlled temperatures is safe. However, when processed either by frying or refined at temperatures above 200 degrees Celsius, can encourage the spread of cancer. CHUKWUMA MUANYA, Assistant Editor writes.
Palm oil is a vegetable oil from the fruit of the palm tree (Elaeis guineensis), which originated in West Africa and is now widespread throughout the tropical areas of America and South East Asia. From the seeds of the palm tree, another vegetable oil, palm kernel oil, is obtained, which has a composition different from that of palm oil and is mainly used for non-food applications.
Until now, red palm oil has been shown to contain high concentrations of beta- and alpha-carotene, and is presumed to possess a higher vitamin A value than other foods.
However, a recent academic study published last week in Science Daily has linked palm oil to the aggressive spread of cancer.
The academic study came out in early December claiming to find a link between palm oil, one of Nutella’s main ingredients, and the aggressive spread of cancer in mice. Nutella, popular in the United States (U.S.) and Europe, is the sweetened hazelnut cocoa spread. The chocolate spread relies on palm oil for its smooth texture and considerably long shelf life.
According to Nutella’s website, palm oil is the second ingredient in the spread and gives it “its creamy texture” as well as its “smoothness” and “special spread-ability.”
According to Reuters and the Schuster Institute for Investigative Journalism, palm oil is cheaper than any alternative vegetable oil and is used in hundreds of processed food products around the globe.
However, a report by the European Food Safety Authority (EFSA) declared it to be more carcinogenic than any other oil, following similar claims by the World Health Organisation (WHO). Why could refined palm oil by cancerous? The detailed EFSA report, published in May 2016; said palm oil is more dangerous than other vegetable oils when refined at temperatures above 200 degrees Celsius (200C).
High temperatures are used to remove palm oil’s natural red color and neutralize its smell. This process, however, causes contaminants called glycidyl fatty acid esters (or, GE) to form.When digested, GE has a tendency to break down and release glycidol, a compound strongly believed to cause tumors.According to a report by the US National Institutes of Health, oral exposure to glycidol has caused tumors at many different tissue sites in lab mice and lab rats.
However, it has been shown that an industrial process that combines a temperature of just below 200C and extremely low pressure minimises contaminants; and the process takes longer and costs 20 percent more than high-temperature refining; and this had allowed it to bring GE levels so low that scientific instruments find it hard to trace the chemical.
Until now, several local and international studies have shown that palm oil from freshly squeezed fruits and processed at controlled temperatures is safe. The WHO and the United Nations Food and Agriculture Organization (FAO) flagged the same potential risk that EFSA had warned of regarding GE, but did not recommend consumers stop eating palm oil.
The U.S. Food and Drug Administration (FDA), also, has not banned the use of palm oil in food.Meanwhile, a study published in the journal Lipids concluded: “…These results suggest that palm oil carotene is able to modulate the immune system by increasing peripheral blood NK cells and B-lymphocytes and suppress the growth of MCF-7 human breast cancer cells.”
Also, another study published in Asia Pacific Journal Clinical Nutrition assessed the bioavailability and vitamin A value of carotenes from red palm oil and found that “the vitamin A values of red palm oil obtained under these conditions, a mean of 0.17 mg retinol absorbed per mg beta-carotene consumed (beta-carotene: retinol equivalency of 5.7:1) is higher than that of all other vegetable sources we have evaluated to date.”
Also, preliminary research suggests that the form of vitamin E packed into the oil-palm fruit, tocotrienol, could help fight cancer and prevent strokes. Though tocotrienols can be found in rice bran, barley and wheat, palm oil has been shown to be the richest source of tocotrienol.
An associate professor in the department of nutrition at Wayne State University in Detroit, US, Pramod Khosla, said numerous test-tube studies done over the past two decades in the U.S., Canada and Malaysia show tocotrienols are “very effective” in killing cancer cells.
Now researchers worldwide are embarking on the critical next step: human clinical trials on cancer patients. “The reason the clinical trials are being done is because the preliminary findings are so promising,” Khosla said. The payoff from these trials could be big: using a natural food-based compound to prevent or treat cancer and stroke.
Another study published in International Journal of Food Sciences and Nutrition concluded:“As regards the role of palmitic acid in cancer risk, speciﬁc studies are few but epidemiological evidence does not support a role of Saturated Fatty Acids (SFAs), palmitic acid or palm oil in cancer development.
From this review, it also emerged that interesteriﬁcation, causing a rearrangement of the palmitic acid which does not naturally occur in the native oil, might be associated with potentially unfavourable effects on heath and should therefore be discouraged.
“Despite striking uncertainties and gaps still persisting in our knowledge of the relationship between dietary fats and health, this review does not clearly provide evidence of a negative role of palmitic acid for health and much less of native palm oil, which is a complex alimentary matrix, in which palmitic acid is only one of its components. Palm oil also contains other fatty acids, mainly oleic acid, as well as antioxidant compounds, whose effects could also be compensatory.
“New lines of research would be necessary to investigate the effects of the single nutrients in combinations, considering the nutrients within each food item and the general dietary pattern so as to develop nutritional strategies aimed at a safe, correct alimentation.”