We hear about diabetes all the time, so it’s easy to forget that there are two very different types of the condition. Both involve problems with insulin, but they deviate from there.
Type 1 diabetes is an autoimmune disease where, in general, people have a complete lack of insulin. People with type 2 diabetes are unable to use their own insulin effectively, either because they don’t make enough or because their cells are resistant to the insulin they do make. (These are the silent signs you might have diabetes.)
“Type 1 is largely a genetic condition, but since not all identical twins get diabetes, we do think that exposure to an additional environmental factor may trigger an immune response that ultimately destroys the insulin-producing cells of the pancreas,” says Sarah Rettinger, MD, board-certified endocrinologist at Providence Saint John’s Health Center in Santa Monica, California. “On the other hand, type 2 diabetes has a stronger genetic component, caused by a complicated interaction of genes and environment. A person with a first degree relative with type 2 has a 5 to 10 times higher risk of developing the disease than a person the same age and weight without the same family history.”
According to the 2014 National Diabetes Statistics Report, 29.1 million Americans have the disease. Of these people, one in four of them are undiagnosed and unaware of their condition. The prevalence is twice as high in non-Hispanic black, Hispanic, and American Indian/Alaska Native adults than non-Hispanic white adults, and higher in individuals aged 65 and older (1 in 4). The incidence of both type 1 and type 2 is increasing worldwide, and type 2 accounts for 95 percent of all diagnosed cases in adults. Type 2 is rare in children (5,000 youths diagnosed each year, compared to 18,000 youths diagnosed with type 1 each year) but the incidence increases around puberty.
Men are more likely to develop both types than women. “Both sexes are equally affected by type 1 in childhood, but the incidence is higher in males than in females in adulthood,” says Marina Bassina, MD, clinical associate professor at Stanford University and member of the Science Advisory Council of Beyond Type 1, a philanthropic foundation focusing on educating, advocating, and eventually curing type 1. “Men are at slightly higher risk of developing type 2 than women, which is possibly due to lifestyle factors, body weight, and the fat distribution in the body—abdominal versus in the hips.”
Both types of the disease can develop at any age, but while there is no known way to prevent type 1 diabetes, type 2 diabetes can be prevented with simple diet and lifestyle changes in most cases. There’s also new evidence that type 2 diabetes can actually be reversed.
“Because type 1 patients are unable to produce insulin, it must be administered to them to enable them to absorb glucose (sugar), which is used for energy,” says Jennifer Haythe, MD, assistant professor of medicine at Columbia University and co-director of the Center for Women’s Cardiovascular Health. “There are many oral medications available to treat type 2, though as the disease progresses many patients end up requiring insulin as well. Type 2 can be prevented and delayed with exercise, diet, and maintenance of a healthy weight.”
Treatment of type 1 can be challenging, admits Bassina. “Individuals have an absolute insulin deficiency and require a lifetime of insulin therapy,” she explains. “Insulin is administered either with multiple daily subcutaneous injections or via an insulin pump, a device that delivers insulin 24 hours a day in small increments also subcutaneously, or under the skin. Insulin doses must be carefully balanced with eating and physical activity throughout the day and night. There is a significant advancement in insulin and insulin delivery devices but the treatment still presents significant challenge and burden to the patients. Multiple research studies are currently under way to try to find a cure for type 1.”
While both types of diabetes put patients at high risk of complications, including damage to the kidneys, eyes, heart, and brain, a diagnosis does not necessarily lead to complications. “Uncontrolled blood sugars lead to complications over time,” explains Rettinger. “This is a progressive disease even in patients with excellent lifestyles. When we see patients frequently (every three months), we can recognize blood sugar patterns, make lifestyle recommendations, and intensify treatment before sugars get out of control. When patients get regular checkups, we can also detect the early signs of complications, often slowing down, or reversing the problem. With good control, patients should be able to live healthy, happy, long lives without complications.”