Extra Virgin Olive Oil on Glycemic Control ,Insulin Resistance and Insulin Secretion

Effect of Extra Virgin Olive Oil on Glycemic Control ,Insulin Resistance and Insulin Secretion in Patients With Type 2 Diabetes

Aim of this study to evaluate the effects of extra virgin olive oil on glycemic control ,insulin resistance and insulin secretion in patients with Type 2 diabetics.

Diabetes is a major health problem and one of the leading causes of morbidity and mortality worldwide. Lifestyle and particularly dietary habits are considered key issues in both the prevention and management of the disease aimed at achieving an adequate glycemic control or at delaying the onset of diabetic chronic complications . Olive oil (OO) has been recognized for centuries for its nutritional properties and considered as the "elixir of youth and health" by antique Greeks. Extra virgin olive oil is the main source of dietary fat in the Mediterranean diet . Consumption of extra virgin olive oil might exert beneficial effects in the prevention, development and progression of T2D compared with refined olive oil . Several bioactive ingredients within OO have been repeatedly linked with anti-oxidant and anti-inflammatory preventative functions, particularly those from monounsaturated fatty acids (MUFA), and key biophenols such as oleuropein and hydroxytyrosol (HT) . Biophenols may influence glucose metabolism via several mechanisms; inhibition of carbohydrate digestion and glucose absorption in the intestine, activation of insulin receptors and glucose uptake in the tissues, antioxidative properties, potent free-radical scavenging and immunomodulatory effects. Multiple studies proven that EVOO improve metabolic control by affection of adipokines .The inhibition of carbohydrate digestion and absorption takes place through an inhibition of some digestive enzymes, especially the carbohydrate-hydrolyzing enzymes α-amylase and α glucosidase. Inhibition of these enzymes retards carbohydrate digestion, thus causing a reduction in glucose absorption rate .With their antioxidative properties, polyphenols diminish the production of advanced glycosylated end products such as HbA1c, AGEs, which are readily formed and accumulated with sustained hyperglycemia, contribute to the development of diabetic complications. As a consequence, inhibition of AGE formation constitutes an attractive therapeutic/preventive target . Studies both in healthy subjects and in persons with type 2 diabetes mellitus have demonstrated that levels of GLP-1are increased more by dietary MUFA than by dietary saturated fatty acids, and that the greater postprandial clearance of an oral overload of MUFA-rich fats is associated with a greater increase in postprandial incretins such as GLP-1 or gastric inhibitory polypeptide. MUFAs from olive oil, therefore, appear to significantly increase the insulin and GPL-1 secretion .

During the experimental period (3 months ), participants will be requested to consume daily dose of 30 mL (3 tablespoons) of HP-EVOO ( high polypheol Extra virgin olive oil)

During the experimental period (3 months ), participants will be requested to consume daily dose of 30 mL (3 tablespoons) of HP-EVOO

change of HBa1c (glycated hemoglobin) after intervention by 30 ml extra virgin olive oil daily for three months and comparison that with other group (no intervention of olive oil) to evaluate glycemic control . measurment of HBa1c for group of intervention at baseline and after 3 months intervention . and other group (no intervention of olive oil) at baseline and after 3 months.

change of fasting glucose after intervention by 30 ml extra virgin olive oil daily for three months and comparison that with other group (no intervention of olive oil) to evaluate glycemic control . measurment of fasting glucose for group of intervention at baseline and after 3 months intervention . and other group (no intervention of olive oil) at baseline and after 3 months.

measurement of fasting insulin after intervention by 30 ml extra virgin olive oil daily for three months and comparison that with other group (no intervention of olive oil) to evaluate insulin resistance and insulin secretion by calculating HOMA -IR and HOMA-B The HOMA-beta cell function (HOMA-B) will be calculated by using the following formula: 360 x fasting insulin (μU/mL) / (fasting glucose (mg/dL) - 63). (HOMA-IR) method: fasting glucose (mg/dl) x fasting insulin / 405

measurement of systolic and diastolic blood pressure after intervention by 30 ml extra virgin olive oil daily for three months and comparison that with other group

height , weight measuring and calculating BMI.Body mass index (BMI) was calculated as weight (kg) divided by squared height (m).

waist circumference change will be measured by tape measure at the umbilical level while patients standing after expiration by centimeter after intervention by 30 ml extra virgin olive oil daily for three months

change at Lipid profile (cholesterol, TG, LDL, HDL) (cholesterol by mg/dl ,triglyceride by mg/dl ,low density lipoprotein by mg/dl and high density lipoprotein by mg/dl ) after intervention by 30 ml extra virgin olive oil daily for three months and comparison that with other group (no intervention of olive oil)

Inclusion Criteria: - Patients with type 2 diabetes with age 30-60 years regardless of their gender. Duration of diabetes less than 5 years. on oral antihyperglycemic medication. willing to participate in research. Exclusion Criteria: Type 1 diabetes. Insulin treated type 2 DM patients. Pregnant women . Patients on cholesterol-lowering drugs, steroids and other drugs that affect the fat metabolism. Patients on regular (days) supplement that contain olive oil. Patients have aversion or allergy to olive oil. Smokers . Patients have gall bladder disease ,gastrointestinal disease (e.g.malabsorption),liver,kidney,heart and thyroid diseases.

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