Researchers from The University of Jaén in Spain have recently published a study in the journal, Nutrients, showing how diets rich in extra virgin olive oil can help prevent colorectal cancer.
Colon cancer is a type of cancer that starts in the large intestine. Colon cancer is sometimes called colorectal cancer (CRC), which is a term that combines colon cancer and rectal cancer, which begins in the rectum. Though colorectal cancer is more common in older adults, rates have increased in patients younger than 45 years old. Scientists have hypothesized that changes in the microbiome may be behind the rise.
Western-style, high-fat diets are thought to be a factor in the development of colorectal cancer. CRC is 3-4 times more common in developed nations. Researchers are studying gut microbiota and thousands of microbial species to understand the relationship between gut bacteria and cancer.
Although high-fat diets have been identified as promoting the development of colorectal cancer, not all types of fats have the same health effect. Animal fats are thought to promote cancer while plant-based fats are assumed to be healthy. However, not all plant-based fats are created equal. For instance, each has a different fatty acid profile which will change its impact on gut microbiota. And most commonly used cooking fats (corn, canola, soybean, etc.) are refined, whereas extra virgin olive oil is not.
According to José Juan Gaforio, Professor of Immunology at The University of Jaén and head of the study, it is important to increase beneficial intestinal bacteria while decreasing harmful bacteria in the gut. "Scientifically, there is evidence that certain intestinal bacteria that make up the intestinal microbiota, depending on their increase or decrease, are capable of preventing or promoting colorectal cancer."
The researchers from The University of Jaén compared the effect on gut microbiota of high fat diets where the fat consumed was either extra virgin olive oil, sunflower oil and coconut oil. Extra virgin olive oil is primarily monounsaturated fat, sunflower oil is mostly polyunsaturated fat and coconut oil is primarily saturated fat.
The study found that extra virgin olive oil primarily caused bacterial changes that can be associated with the prevention of colorectal cancer while coconut and sunflower oil primarily produced changes that are associated with an increase in CRC risk.
As shown in the below chart, EVOO was shown to reduce risk while coconut and sunflower were found to increase risk.
Previous studies have compared extra virgin olive oil and refined olive oil on gut microbiomes. The research concluded that the polyphenols and minor components of EVOO may have a positive impact on intestinal microbiota.
 The High-Fat Diet Based on Extra-Virgin Olive Oil Causes Dysbiosis Linked to Colorectal Cancer Prevention.
 Refined versus Extra Virgin Olive Oil High-Fat Diet Impact on Intestinal Microbiota of Mice and Its Relation to Different Physiological Variables