Diabetes mellitus - often referred to simply as diabetes - is a condition in which the body either does not produce any insulin (Type 1) or not enough insulin. Insulin is a hormone produced in the pancreas to overcome the underlying insulin resistance of the cells in the body (Type 2). Insulin enables glucose (sugar) to enter the cells in order to be stored as glycogen or oxidized for energy. These defects cause glucose to accumulate in the blood, inevitably leading to serious complications. The positive effects of moderate wine and other alcoholic beverage consumption are only relevant for individuals with type-2 diabetes.
Type 2 Diabetes
The underlying defect is insulin resistance due to obesity and lack of exercise. Insulin resistance means that the cells do not respond to the insulin signal. In return, the pancreas tries to overcome this resistance by increasing the insulin output which enables the glucose to enter the cells. Once the beta-cells cannot compensate the high demand of insulin for proper function, the glucose will remain in the blood leading to an increased blood sugar level. Approximately 90% of all cases of diabetes worldwide are type 2.
In 2010, the International Diabetes Federation estimated the global prevalence of diabetes mellitus at 6.6% in adults. Type-2 diabetes is now one of the most common non-communicable diseases in the world and a major cause of premature illness and death in most countries. To prevent diabetic complications and premature death, patients are recommended to adopt a healthy lifestyle.
Evidence from randomized-controlled intervention studies as well as from population studies have demonstrated that light to moderate consumption of alcoholic beverages will improve insulin sensitivity in insulin resistant people. Accordingly, large prospective studies have shown a reduced risk for developing the metabolic syndrome (MS, name for a group of risk factors that raise the risk for heart disease, stroke and diabetes. A metabolic syndrome exists when at least 3 of the following risk factors are present: overweight, high triglyceride level, elevated plasma glucose level, low HDL cholesterol level and high blood pressure) . A moderate intake of wine as well as other alcoholic beverages exerts a beneficial effect on MS. In addition, large population studies suggest that light to moderate consumption of alcoholic beverages is associated with a lower diabetic risk than abstaining or heavy drinking, independently of the type of alcoholic beverage consumed. Meta-analyses reported a J-shaped relationship for men and women with a reduced risk for a moderate intake of alcoholic beverages and an increased risk for more than 50-60 g/d. With regards to wine and diabetes, most studies found beneficial effects. But not only the risk of developing type 2 diabetes is decreased with moderate drinking; it may also reduce CHD and CVD mortality in diabetics as well as potential cardiac complications relating to diabetes. This is especially important considering that coronary heart disease (CHD) is the leading cause of death among individuals with type-2 diabetes, who also have a 4-fold increased risk of having a heart attack or stroke. Research indicates that this risk decreases considerably when they consume wine moderately with meals.
Considering the world-wide epidemic of type 2 diabetes which is expected to rise even further and is associated with major health care costs, preventing diabetes is a major public health issue. It seems that drinking wine in moderation could help reduce type 2 diabetes and thereby contribute to public health.
The above summary provides an overview of the topic, for more details and specific questions, please refer to the articles in the database.