Consumer watchdog weighs in on debate that palm oil increases cancer risk
EUFIC is a consumer-oriented non-profit organisation, founded to make the science behind food and health more accessible and easier to understand among the public and to promote a balanced scientific discourse in the public domain.
Recently, the media reported that palmitic acid – a fatty acid found in palm oil – could increase the spread of cancer in the body, known as metastasis. As a cheap and efficient oil, global consumption of palm oil is rising – thankfully, there is greater focus on sustainable palm oil today – often used in the production of foods like cakes, biscuits, chocolate, margarine and frying fats. It is also found in cosmetics, hygiene and cleaning goods.
The media was reporting the findings of a study – published in Nature on 10 November – that was conducted by two research Institutes in Spain in collaboration with other international researchers to understand if the consumption of specific fats could increase metastasis.
Human cells of mouth cancer were ‘planted’ in mice, which were then fed various diets of several fatty acids (the building blocks of fats), namely palmitic acid found in palm oil, or linolenic and oleic acids that are present in veggie oils.
The researchers found that when mice were fed with a diet rich in palm oil, the cancer cells grew and spread more – an effect that was not observed for linoleic or oleic acids. The researchers did the same experiments in mice with skin cancer and saw similar results.
Ultimately, the scientists concluded their findings highlight potential health risks linked to palmitic acid and also give insights that could lead to new treatments to reduce cancer metastasis.
“There is something very special about palmitic acid that makes it an extremely potent promoter of metastasis,” said Prof Salvador Aznar-Benitah of the Institute for Research in Biomedicine (IRB), Barcelona.
However, he did add, “I think it is too early to determine which type of diet could be consumed by patients with metastatic cancer that would slow down the metastatic process.”
Keep in mind
According to a spokesperson from EUFIC, while this is a good quality study, a few points should be kept in mind when reading the headlines.
- The studies were not carried out in humans, only mice.
Even if animal studies are helpful to understand biological processes that may apply to humans, they still have limitations. For example, the conditions of this experience may not be representative of the typical amounts of palm oil consumed in the human diet.
- The metastatic effect of palmitic acid was only shown with two specific types of cancer cells.
The experiments involved mouth (oral squamous cell carcinoma) and skin (melanoma) cancer cells and cannot be generalised for other types of cancer.
- The study does not suggest that palm oil causes cancer, as claimed in some of the reporting.
The study did not assess if palm oil or palmitic acid causes cancer, only if it affects the spread of cancerous cells.
“Certain media reports stated that palm oil could ‘cause 90% of cancer cases’, but this appears to be a misinterpretation of an experts’ statement that metastasis in general cause 90% of cancer deaths,” said Davide Carrino, area lead of Corporate Communication for the European Food Information Council.
“This is early-stage research and more studies are needed to be certain of the impact of palm oil consumption on the spread of cancer in humans and to understand if findings could pave the way to new treatments to prevent or slow cancer metastasis.”
Cut back on fat
That said, the EUFIC advises that food consumption data highlights that the overall level of fat intake by Europeans is generally higher than the recommended.
The World Health Organization (WHO) recommends that less than 30% of a consumer’s energy intake should come from fats. Of those, a maximum of 10% should come from saturated fats that are present in fatty meats, full-fat dairy products, and palm and coconut oils.
While sustainable palm oil is already a thing, unsustainable palm oil production is still rife and causing large-scale deforestation, forest degradation and soil erosion, along with widespread habitat loss for endangered species like Asian rhinos, elephants, tigers and orangutans. The Roundtable on Sustainable Palm Oil (RSPO) was founded in 2008 to develop a set of environmental and social criteria that companies must comply with in order to produce Certified Sustainable Palm Oil (CSPO).
Dietary palmitic acid promotes a prometastatic memory via Schwann cells
Authors: Gloria Pascual, Diana Domínguez, Marc Elosúa-Bayes, et al.
Nature 599, 485–490 (2021)