You've seen the ads from companies claiming their products can cure diabetes; or maybe you've heard people on TV say they reversed their diabetes. Do they? Did they? Can you cure diabetes?

Can you change your diabetes fate?

It's key to understand that type 2 diabetes is a progressive illness often preceded by years of elevated blood glucose (also known as blood sugar) levels high enough to be diagnosed as prediabetes. When most people with type 2 diabetes are finally diagnosed, experts believe they've been on this path for five to 10 years and have lost more than half of their natural insulin-making capability in the beta cells of their pancreas.

While you cannot undo your lifestyle habits of the last decade or more, you can take steps to put your diabetes in remission. Don't despair and don't give up.

Research shows that losing weight and keeping it off can help delay the onset of prediabetes, delay progression of prediabetes to type 2 diabetes, or slow the progression of type 2. The keys to diabetes prevention and preventing diabetes complications include: Eat healthfully, exercise often, seek out knowledge and support, and create an environment that fosters healthful living.

Losing even just a few pounds early on when glucose begins to rise can dramatically improve your blood sugar levels, cholesterol levels, triglycerides, blood pressure, and more.

"People should get to their ideal weight if they have prediabetes or type 2," says Robert Huizenga, M.D., associate professor of medicine at the University of California, Los Angeles and doctor for The Biggest Loser, where he is known as Dr. H. "People should have no excess fat and be athletically fit. Ninety minutes of exercise six days a week and a steady diet of healthy eating is the best prescription to manage type 2 diabetes without medications."

That's easier said than done for most people, who have to adopt a healthier lifestyle outside the bubble of the ranch where The Biggest Loser is filmed or the jump-start of a stomach-shrinking surgery. Commitment, perseverance, and a positive attitude can help you achieve a healthy weight. Set small, achievable goals first; experience success of meeting those goals; and then add new goals. Over time, all your small successes will add up right before your eyes.

Many research studies suggest setting a goal of losing 5-7 percent of your starting weight to lower blood sugar and improve health, with the imperative to keep the pounds off.

Major research findings offer hope

A decade-plus of research from the National Institutes of Health's Diabetes Prevention Program (DPP) studied people at risk for or with prediabetes. The study showed that people who were involved in the intensive-lifestyle group and lost about 7 percent of their initial weight and kept off some of that weight, initiated exercise, and engaged in support delayed the onset of type 2 diabetes by nearly 60 percent at the end of the three-year phase of the study.

After 10 years, those in the original intensive-lifestyle group continued to reduce their progression to type 2 diabetes the most -- about 35 percent -- and those in the initial metformin group saw about a 20 percent reduction versus standard care. At the 2014 American Diabetes Association annual meeting, 15-year data from the ongoing follow-up study to the DPP, the DPP Outcomes Study, was revealed. This showed a continued reduction in the onset of type 2 diabetes. The original lifestyle group had a 27 percent greater reduction and the metformin group a 17 percent reduction versus standard care.

The conclusions: It appears that losing weight and keeping off as much of it as possible over the years is the main predictor of slowing disease progression. People who lost the most weight had the best chance of preventing type 2. With every 2.2 pounds lost, people reduced the progression to type 2 diabetes by 16 percent. They experienced other benefits, too, including lower blood pressure and improved cholesterol levels, while taking less medication to control them.

People who do progress to type 2 diabetes must pair a healthy lifestyle with glucose-lowering medications to control blood sugar over years. On the upside, M. Sue Kirkman, M.D., endocrinologist and professor of medicine at the University of North Carolina at Chapel Hill, says there are overall health benefits to having normal glucose levels for as many years as possible, such as delaying the onset of complications like heart disease.

So is diabetes 'cure' the accurate term?

Rob Huizenga, The Biggest Loser doctor, uses the word cure, but it comes with a caveat.

"I tell contestants with prediabetes or early-onset type 2 that you're cured at your ideal weight, but should you regain 50 or 100 pounds back, you have a 100 percent chance of revisiting type 2 diabetes," he says.

The terms cure and prevent are misnomers. Remission is the American Diabetes Association's preferred term, which means achieving blood sugar levels below the diagnostic numbers for diabetes without taking glucose-lowering medications. Remission implies the strong possibility of a relapse.

"We know from studies that people can delay progression of prediabetes or type 2 diabetes many years by taking early and aggressive actions," says Robert Ratner, M.D., chief scientific and medical officer for the American Diabetes Association (ADA). "Delaying diabetes results in fewer health problems and savings to the health care system. If you've put prediabetes or type 2 diabetes in remission, get an A1C test annually. And by all means continue to live a healthy lifestyle."

Endocrinologist Sue Kirkman also prefers the term the ADA uses. "Remission implies the strong possibility of a relapse with weight regain and aging," she says, adding that there's even a high rate of relapse among people who have had gastric-bypass surgery.

The reality is that a diagnosis of prediabetes or type 2 should initiate a full-court press to control blood sugar, cholesterol, and blood pressure.

If you put your prediabetes or type 2 diabetes in remission, you cannot remove it from your checklist of health concerns. Make sure any new health care provider is aware of your history. The ADA has no specific recommendations for follow-up, but Kirkman suggests getting an A1C test once or twice a year to keep tabs on your status and progression.

An A1C blood test is one of the best tools to diagnose prediabetes and diabetes. The test reflects the average of your blood sugar levels over three months. Prediabetes is an A1C test result greater than 5.7 percent and less than 6.4 percent. A diagnosis of type 1 or type 2 diabetes occurs when an A1C result is greater than 6.5 percent.

Type 1: Is a cure on the horizon?

Unfortunately, a cure, remission, or reversal for type 1 diabetes won't happen anytime soon.

"A complete cure -- one which prevents the autoimmune destruction of the pancreatic beta cells -- still seems far off," says Kelly L. Close, PWD type 1, editor in chief of the e-newsletter diaTribe. "Fifteen to 20 years is my prediction."

Jay S. Skyler, M.D., Type 1 Diabetes TrialNet study chair and professor of medicine at the University of Miami and the Diabetes Research Institute, is even more cautious. "It's not correct to call any current treatment a cure because what appears as prevention now may not prevent the diagnosis later in life," he says.

Skyler and Close agree that substantial progress is being made on numerous research fronts that will lead to better treatments and, in time, cures.

On Close's growing list are human- or animal-derived stem cells; insulin-making beta cells for transplants, along with improved ways to keep the cells alive and working; approval of once-a-day insulins that respond to a person's glucose level; and oral and nasal insulin vaccines. On the nearer horizon are various artificial-pancreas systems. Stay tuned.