Extra Virgin Olive Oil and Insulin Resistance

September 2026

Insulin is a hormone made by the pancreas and functions to stimulate the storage of glucose into cells.  Insulin resistance is an abnormal situation that means the insulin you are producing is not working properly so it is not effectively storing blood glucose.  Insulin resistance leads to an increase in blood insulin to compensate for the resistance, and an increase in fasting blood glucose, as glucose is not been completely stored.  Insulin resistance is an inherited condition with the gene being “turned on” by an increase in body fat, especially central body fat, which is manifested as an increase in waist size. Central body fat typically means an increase in visceral fat or the fat that surrounds organs, especially the liver.  Insulin resistance is not a healthy situation and is the basis for a condition known as the “metabolic syndrome”.  

The metabolic syndrome, as defined in the US, refers to having three or more of the following risk factors.  These are all variables that can be measured by your doctor during a clinical appointment.  The risk factors are:

·       Blood pressure that is 130/85 mm/Hg or higher.  Either the top or bottom number could be elevated. If you are taking any blood pressure medicines, this variable would count.

·       Fasting triglycerides that are 150 mg/dl or higher.

·       HDL less than 40 mg/dl for men, 50 mg/dl women.

·       Fasting blood glucose 100 mg/dl or higher.

·       Waist measurement of 40 inches or more for men, 35 inches or more in women.  A large waist is related to an increase in visceral fat.  This measurement is not your pants size, but it refers to a measurement that is done by someone standing behind you using a cloth measure and taking the measurement at the smallest part of your waist as viewer from the back. This is not a measurement at your umbilicus/ belly button.

Having the metabolic syndrome is a health concern as if untreated, it can lead to the development of type 2 diabetes, cardiovascular disease, and some cancers.

Fortunately, all of the metabolic syndrome variables can be improved with weight loss and appropriate diet/ food.  The weight loss benefits start when you have lost about 5% of your baseline body weight, so the weight loss does not have to be very much before you see a benefit. Hypertension, total HDL and HDL function, and fasting blood glucose can all be improved with daily EVoo. 

The effect of EVoo on blood pressure:

Starting at two tablespoons per day, EVoo can decrease blood pressure. ^1-3  The amount of total EVoo phenols and specific EVoo phenols may be important as two studies using an EVoo with a total phenol greater than 360 mg/kg lowered diastolic but not systolic BP, ^4,5 while another lowered systolic but not diastolic BP. ⁶  While more studies are needed, a total phenol greater than 500 mg/kg may be needed to lower both systolic and diastolic blood pressure. ⁷

The effect of EVoo on HDL:

HDL is one of the carriers of the blood fats cholesterol and triglycerides.  Higher levels of HDL have been related to lower risk of heart disease so HDL is considered a healthy way to carry blood fats.  Starting at two tablespoons, daily consumption of EVoo has been shown to increase HDL levels ^8-11 and to improve HDL function, even if the level of HDL does not change. ¹² The ability of EVoo to increase HDL and improve function is intriguing as that there is currently no medicine that has been shown to independently increase HDL. The medications currently designed to try and improve HDL levels work by decreasing fasting triglycerides as there is an inverse relationship of fasting triglycerides to HDL levels, meaning when fasting triglycerides decrease HDL will increase and vice versa.

The effect of EVoo on fasting blood glucose:

Fasting blood glucose is also called “fasting blood sugar” as glucose is the main form of carbohydrate in the blood.  Blood glucose is a very important source of energy for our body, but when the fasting level is 100 mg/dl or higher it means that your body is not able to store and use blood glucose as well as it should.  A more accurate measure of blood glucose is A1c, which measures how much glucose is attached to the protein hemoglobin in your blood. A1c measures your blood glucose for the past three months and is represented as a percentage number.  A healthy level of A1c is 5.7% or lower.  A vale of 6.2% or higher indicates type 2 diabetes; values between 5.7% to 6.2% indicate insulin resistance.

Increasing fasting blood glucose is an indicator that you have insulin resistance or the insulin you make in your pancreas to store nutrients is not working properly. Higher blood levels of fasting glucose mean that you are at risk of becoming a type 2 diabetic.  It also means that if your blood glucose level stays too high that over time this will increase your risk of heart disease and a number of different cancers.  Most of the published studies examining the effect of EVoo on fasting blood glucose and insulin are of participants with normal values for blood glucose, which limits the usefulness of the results.  A study comparing daily EVoo to sunflower oil in type 2 diabetics found EVoo significantly decreased both fasting blood glucose and insulin. ¹³ A follow-up study by the same group found that EVoo can improve insulin sensitivity, ¹⁴ which means EVoo can make insulin work better.  More studies are needed to better understand the role of EVoo in improving insulin sensitivity and blood glucose control, but the current data are promising.

The US definition of the metabolic syndrome does not include body weight as the abnormal variables can occur at what is considered a “normal” BMI (body mass index, kg/m2).  However, excess body fat can result in the development of the metabolic syndrome, especially if there is excess body fat at the waist.  Published studies provide evidence that daily EVoo can improve body weight, compared to other diets. For example, a diet rich in daily EVoo has been shown to result in better weight loss compared to a lower fat diet; ^15,16 and one of these studies found a larger decrease in waist circumference with daily EVoo.¹⁵ Compared to a diet with daily soybean oil, daily EVoo was shown to result in greater loss of body fat, despite similar weight loss. ³ Additionally, while a study in men found no difference in weight loss with daily EVoo compared to a low-fat diet, the EVoo diet showed an improvement in insulin sensitivity. ¹⁷

Summary:

•         Starting at two tablespoons a day, Laconiko Everyday High Polyphenol EVOO can lower the metabolic syndrome variables of fasting blood glucose, blood pressure, and waist circumference, and increase HDL. ¹⁸ 
•         More studies are needed to assess the impact of EVoo on insulin and blood glucose in type 2 diabetics.

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2.         Ferrara LA, Raimondi AS, d'Episcopo L, Guida L, Dello Russo A, Marotta T. Olive oil and reduced need for antihypertensive medications. Arch Intern Med 2000;160(6):837-42. (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=10737284 ).

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13.       Madigan C, Ryan M, Owens D, Collins P, Tomkin GH. Dietary unsaturated fatty acids in type 2 diabetes: higher levels of postprandial lipoprotein on a linoleic acid-rich sunflower oil diet compared with an oleic acid-rich olive oil diet. Diabetes Care 2000;23(10):1472-7. (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=11023139).

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15.       Estruch R, Martinez-Gonzalez MA, Corella D, et al. Effect of a high-fat Mediterranean diet on bodyweight and waist circumference: a prespecified secondary outcomes analysis of the PREDIMED randomised controlled trial. Lancet Diabetes Endocrinol 2019;7(5):e6-e17. DOI: 10.1016/S2213-8587(19)30074-9.

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18.       Flynn MM, Tierney A, Itsiopoulos C. Is Extra Virgin Olive Oil the Critical Ingredient Driving the Health Benefits of a Mediterranean Diet? A Narrative Review. Nutrients 2023;15(13). DOI: 10.3390/nu15132916.