One third of Americans may be on their way to developing full-blown type 2 diabetes, and most of them don't even know it. A recent report from The Centers for Disease Control and Prevention (CDC) shows that more than 84 million Americans, or roughly one-third of the population, have prediabetes, a condition marked by higher-than-normal blood sugar. Of that group, 90 percent aren't aware they have the condition. The primary risk factors for type 2 diabetes are genetics and lifestyle — excess weight, obesity and lack of exercise contribute to this alarming medical trend. "People with prediabetes who don't change their lifestyle are at a much higher risk of developing heart disease and stroke and can develop type 2 diabetes within five years if left untreated," said William T. Cefalu, MD, chief scientific, medical & mission officer of the American Diabetes Association. The health risks go beyond heart disease and stroke. As diabetes worsens over time, blindness, kidney disease and lower-limb amputation are also major health risks. Diabetes was the seventh-leading cause of death in the United States in 2015, according to the CDC. This population of diabetes "ticking time bombs" is particularly alarming, because in many cases type 2 diabetes can be avoided, simply by leading a healthy lifestyle. Type 2 diabetes is often progressive, and within 10 years of diagnosis, 50 percent of individuals need to use insulin to control their blood glucose levels, according to the ADA. More than 30 million Americans — 9.4 percent of the U.S. population — are already battling diabetes, according to the CDC's National Diabetes Statistics Report, which used data through 2015. The CDC found that of those cases, 7.2 million were undiagnosed. "The country needs to take this seriously, ratchet it up and make it a priority," said Ann Albright, PhD, RD, director of CDC's Division of Diabetes Translation. "Far too few people know about it or know they have it, and that is why we launched the prevention program and joined forces with other organizations," she said. "It requires us all to take this condition seriously."

What prediabetes is, and how you get it

Prediabetes is a condition in which a person's blood glucose (sugar) levels are higher than normal, but not yet high enough for a type 2 diabetes diagnosis. Doctors often refer to prediabetes as impaired glucose tolerance (IGT) or impaired fasting glucose (IFG), depending on which test they used to detect the condition. The A1C test is the most commonly used to detect the condition, because it is a blood test that provides information about a person's average blood glucose levels over the past 90 days. To be prediabetic, an individual would have to have an A1C result of 5.7 percent — 6.4 percent. The results of a fasting glucose test that are 100-125mg/dl indicate IFG. If an oral glucose tolerance test is performed and the result is 140-199, it indicates IGT. All are considered prediabetes. More from Modern Medicine:

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ER costs are skyrocketing, leaving patients in shock The cost to the American health-care system and economy from diabetes is steep. The American Diabetes Association estimates at least $245 billion a year. Medicare, Medicaid and the military foot a large portion of that bill, paying for 62.4 percent of the cost of care, while 34.4 percent is paid for by private insurers and 3.2 percent by the uninsured, according to the ADA. The medical community has so far failed to contain prediabetes. A big part of the problem: People simply avoid going to the doctor. William Argenta was 48 when he was diagnosed with type 2 diabetes, a couple of years ago. He had not been to a doctor in more than five years and only received the diagnosis when he finally decided to go in for a physical. He had experienced a feeling of being overly thirsty — often a sign of diabetes — but other than that, he didn't see any reason to get checked out.

I guess I had just gotten used to feeling bad. Your body adjusts to it in some ways. William Argenta diagnosed with diabetes at age 48

Once a patient is diagnosed with prediabetes or type 2 diabetes, they are advised to change their eating and exercise habits. Many are prescribed metformin — it is the most widely prescribed drug for diabetes under many brand names, including Glucophage — and helps control blood sugar levels. Metformin lowers blood glucose by reducing the amount of glucose produced by the liver and by helping the body respond better to the insulin made in the pancreas. The FDA has approved metformin for treatment of type 2 diabetes, but not for prediabetes, which is a serious health condition but does not reach the blood sugar level to be diagnosed as type 2 diabetes. The FDA has been conservative about approving drugs for use beyond specific disease states. However, the FDA is now considering approval of metformin for use in prediabetes. While physicians can already administer it at their own discretion, the ADA says the drug is currently underused as part of treatment options. Ongoing follow-up to the federally funded Diabetes Prevention Program research study has shown that metformin has long-term cost-saving value in delaying type 2 diabetes, with great safety and low cost to the consumer, which may persuade the FDA to approve an indication for prediabetes. According to the ADA, metformin therapy for prevention of type 2 diabetes should be considered for people who have a high body mass index BMI, are aged 60 years or older, have rising A1C test results, despite lifestyle intervention, and for women with prior pregnancy-related glucose intolerance. There are several other drugs prescribed for prediabetes, including a weight loss drug, but many have significant side effects. The ADA states that metformin has the best track record and safety profile. The ADA also notes that even metformin has been shown to be less effective than lifestyle modification — lifestyle changes can slow or prevent type 2 diabetes in some individuals with a genetic predisposition. Now a type 2 diabetic, Argenta has changed his lifestyle. He cut down on sugary food and has increased his protein intake. He is also exercising and taking metformin and a couple of other medications. Argenta says he now feels much better than he did before he was diagnosed. "I guess I had just gotten used to feeling bad. Your body adjusts to it in some ways," he says.

The CDC, ADA and the American Medical Association have launched a new prediabetes awareness campaign, DoIHavePrediabetes.org. The campaign encourages people to take an online test of seven simple questions that can assess a person's prediabetes risk. The organizations are also beseeching those at risk to change their eating and exercise habits before their condition worsens. Dr. Rhonda Todd, MD, internal medicine, is doing her part to raise prediabetes awareness. Based near Ann Arbor, Michigan, she tries to test as many of her patients as she can for prediabetes if they fit a risk profile, using the A1C test. Most private insurers cover the expense of an A1C test, as do Medicaid and Medicare when the patient present risk factors. Todd said she has never had a problem getting a test approved. The cost of the test is roughly $50 dollars, but Todd has seen some hospitals offer the test for $10, as a part of wellness programs. "I will try to test every patient I see who is over 35, has a family history of the disease or who is obese or overweight, which is almost everybody," she says. Todd blames the sedentary lifestyle of Americans for the explosion of diabetes and prediabetes cases. "We are not a healthy people anymore, technology is killing us," she said. Todd said the majority of doctors, many of whom are affiliated with hospitals, test for prediabetes often. She thinks the bigger problem is people not going to the doctor rather than doctor's not offering the tests. The ADA recommends testing for prediabetes in adults of any age who are overweight or obese and who have one or more additional risk factors. For all people, testing should begin at age 45 years and be carried out at a minimum of three-year intervals.

The numbers are staggering

Every 21 seconds another person in the United States is diagnosed with diabetes, according to the ADA. That's 4,110 people in America diagnosed with the disease every 24 hours. Type 2 diabetes accounts for 90 to 95 percent of all those cases. The risk for developing the disease also increases drastically in people age 45 and older, and after age 65 it increases exponentially. There has also been a troubling rise in the number of adolescents developing both prediabetes and diabetes. Weight has a lot to do with it. Among adolescents, ages 12 to 19, about 1 in 5 are considered to have obesity, and about 1 in 11 (9.1 percent) are considered to have extreme obesity, according to the National Institute of Diabetes and Digestive and Kidney Diseases. "Nutrition for adolescents is the cornerstone of treatment," Cefalu said. "People need access to adequate nutrition, and you have to get that information in their hands." Testing for prediabetes in children and adolescents should be considered for those who are overweight or obese, and who have two or more additional risk factors for diabetes, including having a family history of type 2 diabetes, or who are African American, Native American, Latino, or Asian Pacific Islanders. More than half of Asian-Americans and nearly half of Hispanic Americans with diabetes are undiagnosed. Health-care specialists say getting people to change their behavior isn't easy. "Telling people to lose weight does not give them enough information. It is not a message that helps and supports them," Albright said. To teach people how to change and maintain a new set of lifestyle habits, the CDC is also promoting its National Diabetes Prevention Program, which was initiated in 2010. Just by participating and staying in the program, prediabetics can lower their risk of developing type 2 diabetes by as much as 58 percent over three years, and by 71 percent for people over age 60. "We want to help them determine what is realistic and doable so they can make real life changes that are sustainable," Albright said. A DDP program can cost as much as $500 a year. (The CDC-recognized organizations delivering these programs determine the cost, which can vary depending on factors such as the size and experience of the organization offering it.) Diabetes prevention programs are growing in number and participation, but are still underutilized, according to the ADA.

All sectors, including health care, business, nonprofit community organizations and faith-based organizations, need to be talking about prediabetes and encouraging those with prediabetes to enroll in a National DPP lifestyle-change program. Ann Albright PhD, RD, director of CDC's Division of Diabetes Translation