Heart disease. The risk of cardiovascular (heart and blood vessel disease) is 2 to 4 times higher in people with diabetes than in the general population. If diabetes runs in the family, usually so does heart disease. That being the case, your family members should not only stay aware of any risk factors they may have for diabetes but also any that raise the risk of cardiovascular disease, including high blood pressure and abnormal blood fat levels (as described above).
Insulin resistance. Almost all people with Type 2 diabetes have insulin resistance, a condition in which the cells of the body resist the action of insulin. Normally, insulin is the “key” that allows glucose to enter the cells, where it can be used for energy (or stored for later). When the cells resist insulin, the pancreas produces and releases more insulin to overcome the resistance. As long as the pancreas can produce enough insulin, blood glucose levels remain normal. If it can’t, they rise, potentially leading to a diagnosis of prediabetes or Type 2 diabetes.
Insulin resistance likely starts long before Type 2 diabetes is diagnosed. If it could be identified and addressed, a person might never develop Type 2 diabetes. Currently, there is no readily available test for diagnosing insulin resistance, but having a large waist is often a sign of it. In fact, some studies suggest that waist circumference is a better predictor of diabetes risk than BMI, because visceral fat, which accumulates within the abdomen, has more negative effects on health than subcutaneous fat, or fat that collects just beneath the skin. Visceral fat is often associated with an “apple-shape” body, as opposed to a “pear-shape” body, in which fat accumulates primarily in the hips and buttocks.
Aerobic exercise, such as brisk walking, can reduce visceral fat, even when no significant weight loss occurs.
Polycystic ovary syndrome. Usually called PCOS, this common female endocrine disorder is thought to affect 5% to 10% of women of reproductive age and to be one of the leading causes of infertility in women. Because PCOS is associated with obesity and insulin resistance, it is considered a risk factor for Type 2 diabetes. In fact, Type 2 diabetes is 5 to 10 times more common in women with PCOS than it is among women in the general population.
Symptoms of PCOS include infertility, menstrual irregularities, excess body and facial hair, acne or oily skin, and acanthosis nigricans, or patches of thickened and dark brown or black skin.
Prediabetes. People whose blood tests show blood glucose levels that are higher than normal but not high enough for a diagnosis of diabetes are said to be at risk for Type 2 diabetes or to have prediabetes (see “When Is It Diabetes?”). However, even in these individuals, developing Type 2 diabetes is not inevitable. With increased physical activity, the adoption of healthy eating patterns, and a weight reduction of 5% to 10% of body weight, blood glucose levels can be brought back to normal.
Making a difference
You can’t change your family’s genes, but you can help your family members recognize their risk for Type 2 diabetes. One resource you can point them to is a short quiz developed by the American Diabetes Association (ADA) that can be found on the ADA’s Web site. (See “Online Risk Evaluator” for the address.)
Your relatives should also tell their health-care providers about their family history of Type 2 diabetes and discuss when to be tested for it. Adults of any age who are overweight and have any other risk factors should be tested for diabetes. Adults with no risk factors should be tested initially at age 45 and, if those test results are normal, at least every three years afterward. When an adult has risk factors for diabetes but normal blood glucose levels upon testing, a doctor may choose to retest more frequently than every three years.