Olive extract shows benefits for inflammatory bowel disease

Olive oil and the hydroxytyrosol it contains may reduce inflammation linked with the development of colitis, says a new study from Spain.

Researchers from the University of Seville report that hydroxytyrosol-enriched extra virgin olive oil was associated with an improved inflammatory response in a mouse model of inflammatory bowel disease.

"We concluded that besides the beneficial effect by EVOO, supplementation of the diet with hydroxytyrosol may improve chronic colitis," wrote the authors in the European Journal of Nutrition .

Olive compounds

Hydroxytyrosol is thought to be the main antioxidant compound in olives, and believed to play a significant role in the many health benefits attributed to olive oil. Previous research has linked the compound to cardiovascular benefits, with reductions in LDL or 'bad' cholesterol. Data has also suggested the compound may boost eye health and reduce the risk of against macular degeneration.

Several companies already offer the compound for nutraceutical applications. A recent study by scientists at DSM Nutritional Products identified hydroxytyrosol as the main anti-inflammatory compound in olives (Planta Med, doi: 10.1055/s-0031-1280022 ).

New data

The new study involved mice fed one of three diets: A standard diet; a diet supplemented with extra virgin olive oil; or a diet with olive oil enriched with hydroxytyrosol. After 30 days of feeding on these diets, they were exposed to a chemical called dextran sulphate sodium (DSS) to induce inflammation in the colon, and ultimately colitis.

Results showed that the olive oil-fed animals had an attenuation of the colonic damage, as well as a 50% reduction in the mortality rate caused by DSS. The results were improved further by hydroxytyrosol supplement, added the researchers.

Biochemical analysis showed that levels of the pro-inflammatory compound interleuking-10 (IL-10) were "significantly improved" in both olive oil-fed groups.

"We have demonstrated that EVOO diet exerted a significant beneficial effect in chronic DSS-induced colitis," reported the researchers.

"Moreover, supplementation with the phenolic compound contributed to improve inflammatory response," they concluded.