Black olives in a paper bag on a flat surfaceShare on Pinterest
Scientists are looking into a natural compound found in olives to manage obesity and type 2 diabetes. Juan Moyano/Stocksy
  • Obesity raises a person’s risk of developing type 2 diabetes.
  • Researchers from Virginia Tech have found a natural compound in olives and olive oil that might help improve blood sugar control and promote weight loss.
  • This could help researchers develop natural products for managing obesity and type 2 diabetes.

As of 2022, one in every eight people around the world lives with obesity.

Previous research shows that obesity can raise a person’s risk for several health concerns, including type 2 diabetes.

“It has been well established that obesity is a leading pathogenic factor for developing type 2 diabetes, and it is also a major obstacle for effective metabolic control in many patients with type 2 diabetes,” Dongmin Liu, PhD, professor in the Department of Human Nutrition, Foods and Exercise at Virginia Tech explained to Medical News Today.

“However, lifestyle modifications and public health measures apparently have very limited impact on the rising prevalence of obesity, and available obesity and diabetes pharmacotherapy may not be effective long term, difficult in sustaining weight loss maintenance, expensive, or carries long-term safety risks.”

“In addition, existing treatments for obesity and diabetes may not work for everyone,” Liu continued. “Therefore, developing new, cheaper treatments, particularly using natural products either as a primary or secondary adjuvant treatment can provide more options and may improve outcomes for a wider range of patients.”

Liu is the lead author of a new mouse study recently presented at NUTRITION 2024, the flagship annual meeting of the American Society for Nutrition, suggesting that a natural compound found in olives and olive oil may help improve blood sugar control and promote weight loss.

Liu and his team used a mouse model to conduct their study, which began by identifying natural compounds that affect L-cells, which contain the metabolic hormones PYY and GLP-1 that are released when eating. When these hormones are released, they signal the body to stop eating and help control blood sugar levels.

Researchers identified elenolic acid that is naturally found in olives as a compound that can cause the release of the PYY and GLP-1 hormones into the gut.

“Elenolic acid is a natural compound found in olives and olive oil,” Liu explained. “It’s part of a larger group of substances called polyphenols. Elenolic acid is naturally produced during the maturation process of olive from breaking down oleuropein, the most abundant polyphenolic compound in olive and olive leaf extract-based dietary supplement.”

“We have been studying this compound because it has never been investigated, as to the best of my knowledge, whether it exerts beneficial actions related to health or disease states such as diabetes,” he added.

When obese mice with diabetes were given a dose of oral elenolic acid, scientists reported significant improvements in their overall metabolic health compared to the obese control mice.

After four to five weeks of receiving elenolic acid, researchers found that obese mice with diabetes experienced a 10.7% reduction in obesity.

“This is a healthy effect of elenolic acid as it also increased muscle weight, reversed diet-induced fatty liver disease, and improved liver function,” Liu said. “Fundamentally, oral intake of elenolic acid once a day led to increased secretion of some metabolic hormones from the gut, called GLP-1, PYY, and GIP, which may work together to restrict access calorie intake during feeding.”

Additionally, the blood sugar levels and insulin sensitivity of the obese mice given elenolic acid were comparable to healthy-weight mice within four to five weeks of treatment.

Liu said this finding is significant for two main reasons.

“One, the finding that elenolic acid improved blood sugar levels and insulin sensitivity to the point where they became similar to those of healthy lean mice indicates that it is an effective compound for rectifying the key defects leading to overt diabetes,” he detailed. “Two, the results suggest that elenolic acid could potentially be developed into a treatment for humans with obesity, insulin resistance, and diabetes. If it works similarly in humans, it could offer a new, natural way to manage these conditions.”

“Our next steps for this research are one, to unravel how this compound is able to effectively manage blood sugar control as well as obesity,” Liu continued.

“The key point to address this question is to figure out how it controls food intake. Two, to test the combination therapy with metformin, a first-line anti-diabetic drug, as our preliminary study (shows) that (the) administration of both agents works much better than either one alone. We just received a four-year NIH grant to support these studies,” he explained.

After reviewing this study, Mir Ali, MD, a board certified bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, told MNT he found the findings interesting.

“It’s been known that there are certain compounds in foods that are helpful for lots of conditions like diabetes, obesity, (and) high blood pressure,” Ali continued. “The thing is trying to identify these and apply them to humans. These studies were done in mice that were genetically selected to have diabetes or obesity, so things are obviously going to be different in humans. So the next step would be to try to apply this to human studies.”

Ali said it is important for researchers to continue to find new ways of treating obesity and diabetes because at least right now there’s no one perfect way to treat every patient.

“Everybody responds differently to medications, everybody’s genetic makeup is different, so the more options we have to help people, the better,” he added. “And one day they may find the key that may make it applicable to a larger number of people.”

MNT also spoke with Monique Richard, MS, RDN, LDN, a registered dietitian nutritionist and owner of Nutrition-In-Sight about this study, who commented that given what we know related to a Mediterranean diet lifestyle and the benefits of olives, this study was not surprising.

“The combination of varying types of saturated, mono-unsaturated, and poly-unsaturated fatty acids in olives provides a unique nutrient profile,” Richard continued. “Due to (their) high fat content, mouthfeel, and often savory palatability (i.e.salt, seasonings, oil, herbs) olives are satiating — in other words, can provide a feeling of satisfaction. The interaction of the fatty acid components of the olive within the cells, and therefore, interaction with appetite and insulin receptors has been previously identified with (the) delivery of olive leaf extract in humans as well due to the identified polyphenols, oleuropein, and hydroxytyrosol.”

For those looking to add more olives to their diet, Richard suggested adding a serving of olives (3-8 depending on their size/variety):

  • used to make a tapenade with vegetable crudites
  • as a homemade pizza or pasta topper
  • in an omelet
  • in bean, couscous, or Mediterranean-type salads
  • chopped and used as a relish
  • as a snack or appetizer stuffed with pimentos, garlic, cheese or nuts
  • as a finger food, literally

As for olive oil, Richard said quality matters in the one you choose to use.

“Look for tinted glass bottles, ‘extra virgin (EVOO),’’ ‘cold-pressed,’ ‘organic,’ ‘imported from Spain/Italy/Greece’ on the label,” she added.

Richard advised using quality EVOO:

  • used as a base for sauteing or roasting
  • to make salad dressing

Other ways to use olive oil are to add it to homemade hummus or dips, drizzle it on steamed vegetables, or add it to homemade vegetable or bean soups.

While olives are full of beneficial nutrients, they are prepared and packaged in brine (salt water), which is soaked up by the olives.

“If you are on a sodium-restricted diet, it may be necessary to limit the amount or frequency of olive intake, read the nutrition facts label, and don’t forget to meet with your registered dietitian nutritionist for more individual ideas, tips, and nutrition information,” she added.

While people can get small amounts of elenolic acid from consuming olives, the concentration from olive oil or olives alone won’t likely match the amount of elenolic acid used in the study.

The researchers are now working to explore the mechanisms further to determine the safety of concentrated elenolic acid for human clinical trials in the future.