The US Centers for Disease Control and Prevention (CDC) reports that more than 100 million adults in this country are living with diabetes or prediabetes. Of those, 30.3 million – that’s 9.4 percent of the US population – have full-blown diabetes.

Another 84.1 million US adults have prediabetes. That’s a condition that, if left untreated, can lead to type 2 diabetes within five years. More than a third of adult Americans has prediabetes, and most of them don’t know they have it.

Why should we take note of these figures? Because consistently high blood glucose (sugar) levels, the hallmark of uncontrolled diabetes, can cause serious injury to your body’s nerves and blood vessels, impairing circulation and damaging your heart, liver, brain cells and eyes.

Most serious eye diseases related to diabetes begin when high blood glucose damages the eye’s tiny blood vessels. The four main eye diseases that can threaten the vision of a person with diabetes are diabetic retinopathy, diabetic macular edema, glaucoma and cataracts.

Diabetic retinopathy is the most common cause of vision loss for people with diabetes and the leading cause of blindness for all adults in the US. It occurs when high glucose blocks the tiny blood vessels that nourish the retina, the part of your eye that detects light and sends signals to your brain. These damaged blood vessels can begin to swell and leak fluid. This stage is called non-proliferative diabetic retinopathy.

In some cases, non-proliferative diabetic retinopathy progresses into the proliferative stage. That’s when the eye grows new blood vessels to make up for the blocked vessels in a process called neovascularization. But the newly formed blood vessels are highly unstable and leak and bleed easily.

These leaking blood vessels may even hemorrhage into the jelly-like material that fills the center of your eyes, called the vitreous. Blood in the vitreous results in dark spots that can block vision.

Diabetic retinopathy can also cause scar tissue to form in the back of your eye, which may pull the retina away from the back of the eye. This is called a retinal detachment, and it’s a serious complication that can cause loss of vision if not repaired quickly.

As the unstable blood vessels in your retina continue to bleed, they eventually cause the macula, the area of the retina that enables you to read, drive and see faces, to swell. This condition is called diabetic macular edema. Over time, this condition can destroy your sharp vision and lead to partial vision loss and eventually blindness.

The natural lenses of your eyes are clear structures that provide sharp vision. But over time, they can become cloudy, a condition called cataracts. People who have diabetes can develop cataracts at an earlier age than people without the disease, and people with diabetes are two to five times more likely to develop cataracts. It’s believed that high glucose levels cause protein deposits to build up on the lenses, leading to the cataracts.

Sometimes, blood from the leaking vessels blocks the normal drainage channels for fluid in the eyes. As a result, fluid builds up and pressure in the eye increases, which can damage the optic nerve and affect vision. Glaucoma is a group of eye diseases related to increased eye pressure. Having diabetes nearly doubles your risk of developing a type of glaucoma called open-angle glaucoma.

The best way to prevent vision loss from these eye diseases is to control your blood glucose levels and get regular exams by your eye doctor to look for swelling and changes in the blood vessels in your eyes.

To help control your diabetes, eat a healthy and balanced diet, exercise regularly and maintain a healthy body weight. High blood pressure and high cholesterol can affect your blood glucose level, so take all medications your doctor prescribes for these conditions and get them checked regularly. Don’t smoke and drink alcohol in moderation.

Regular eye exams can help find problems early, when they’re easier to treat. Early detection can save your vision. See you eye doctor yearly or as often as your doctor recommends. Call your eye doctor right away if you experience any of the following symptoms:

• Black spots in your vision
• Flashes of light
• “Holes” in your vision
• Blurred vision

Do you have diabetes? If so, you’re certainly not alone. The American Diabetes Association estimates that 30.3 million Americans have diabetes and another 8.1 million have it but haven’t been diagnosed. Another 84.1 million people in the US have prediabetes, and nine out of ten aren’t aware of it. Still, 1.2 million new cases of diabetes are diagnosed in this country every year.

Maintaining healthy glucose (sugar) levels in your blood is a constant concern if you’ve got diabetes. Consistently high blood glucose can damage many parts of the body, such as the heart, kidneys and blood vessels. That includes the tiny blood vessels in the eyes, which can affect the retina, macula, lens and optic nerve.

When high glucose levels negatively affect the blood vessels in the retina, which is an area of light-sensitive tissue located in the back if the eye, it leads to a condition called diabetic retinopathy. There are two main types of retinopathy, nonproliferative and proliferative.

Nonproliferative retinopathy has several stages. It progresses from mild to moderate to severe. It starts as small areas of balloon-like swelling in the tiny blood vessels. These areas may start leaking fluid into the retina. In the moderate stage, the blood vessels that feed the retina may start swelling and distorting, losing their ability to transport blood.

In severe nonproliferative retinopathy, many blood vessels become blocked, which deprives the retina of its nourishing blood supply. Growth factors are also released during this stage. These factors initiate the development of new blood vessels.

Retinal Detachment

In some people, the severe stage progresses into proliferative retinopathy. With that, new blood vessels start growing, but these vessels are very fragile and weak. They can leak blood, which can block vision. Scar tissue can also be created, which can cause the retina to pull away from the back of the eye, a condition called retinal detachment.

Another consequence of retinopathy is macular edema, which is swelling, or the build-up of fluid, in the macula. The macula is the area of the retina responsible for central vision. It’s the macula the enables you to recognize faces, read and drive. Macular edema is the most common cause of vision loss in people who have diabetic retinopathy.

Cataract

If you maintain good control of your blood glucose levels and your blood pressure, you’ll be less likely to develop diabetic retinopathy or, if you do, you’ll get a milder form of it. Those are risk factors you can control. Risk factors you can’t control are your genes and how long you’ve had diabetes.

Having diabetes puts you at higher risk for other eye conditions as well, including cataracts and glaucoma. Rapidly changing blood glucose levels can affect the eye’s lens and cause it to become cloudy. This can lead to a cataract. Anyone can get cataracts, but people with diabetes tend to get them earlier, and they progress faster.

Trabecular Meshwork

With glaucoma, pressure builds up inside the eye when fluid can’t be removed through the eye’s drainage system that includes the trabecular meshwork. High blood glucose levels damage the cells of this meshwork, so it can’t function properly. Fluid doesn’t drain and pressure builds up in the eye. If not treated, the pressure can damage the optic nerve, leading to permanent vision loss.

Diabetic retinopathy, macular edema and glaucoma usually have no early symptoms. You may not know you have these diseases until they’ve already done damage to your eyes and affected your vision. That’s why an annual examination by an eye specialist is so important. The specialist can check your eyes for signs of these disorders, so early treatment can be started.

According to the US Centers for Disease Control and Prevention, about 90 percent of diabetes-related vision loss can be prevented. Early detection is one of the ways to reach that goal, and it’s another reason for an annual eye exam. Another way to help prevent vision-stealing eye diseases is by maintaining good blood glucose and blood pressure control.

Following these simple tips can help save your vision. So can knowing these symptoms  that signal an emergency. If you notice any of these symptoms, call your doctor right away:

• Black spots in your vision
• Flashes of light
• “Holes” in your vision
• Blurred vision

Surprising research demonstrates the elderly have an advantage in preventing Type 2 diabetes by making lifestyle changes.

Over 60 and at risk for diabetes? Your age may be an advantage.

A few years ago, the Center for Disease Control (CDC) rolled out a national program designed to combat one of our country’s most insidious health problems: diabetes. A year-long program designed to help participants make lasting lifestyle changes, the National Diabetes Prevention Program (NDPP) provides practical solutions on how to eat healthier, include physical activity into daily life, and improve problem-solving and coping skills.

The program’s success may lie in the age-old “accountability factor” – not only are participants required to report their weekly diet and exercise progress to a lifestyle coach, they have to be accountable to each other. For six months, they meet weekly in a small group to ideally share improvements. They continue to meet once a month for six months after that.

While older folks know the physical limits of aging all too well, in the case of lifestyle modifications affecting change, NDPP participants over 60 have a documented advantage.

Reported by The New York Times, a large national clinical trial showed that among adults at risk for Type 2 diabetes, this lifestyle modification program and resulting weight loss reduced the incidence of the disease by 58% in 1,000 subjects participating in the NDPP, compared with those who did not.

If you think those numbers are impressive, check out the stats for NDPP participants over the age of 60: a whopping 71% reduction in the incidence of Type 2 diabetes for this age group.

Offered in every state, often at multiple sites, over 527 organizations (community groups, employers, colleges, churches) offer the program, with the Y.M.C.A. enrolling 40 percent of participants nationally. Ann Albright, who directs the diabetes division of the C.D.C. estimates that in the first two years of the program, almost 50,000 Americans have joined an NDPP, which are aimed at people whose weight, blood glucose levels and other factors suggest they are at elevated risk for developing the disease.

Dr. Albright notes that the program is not a “quick-fix weight loss gimmick” but rather a series of lifestyle changes designed to create long-term behavior modification.

Whatever it is, it’s working.

Dr. Albright says that while a four percent reduction of body weight can produce diabetes reduction, the program shoots for five to seven percent. In Y.M.C.A. programs, the organization says, participants average a 5.7 loss after a year.

The elderly advantage

As noted, those over 60 are particularly successful in the program, with a 71% reduction in the incidence of diabetes, as compared to a 58% reduction in other age groups.

So, why do older NDPP participants do exceptionally well?

“It probably has to do with their commitment,” muses Dr. Albright. “They become more engaged. Maybe they realize where they are in their life course.”

Perhaps they also see more diabetes, and its destructive effects. Dr. Albright tells The New York Times that close to ten% of the population has Type 2 diabetes, diagnosed or undiagnosed, and prevalence only rises with age: for those over age 65, nearly 26 percent have the disease.

Feasibly, seeing the life-limiting effects of diabetes in their friends and neighbors motivates those over 60 to commit, and remain committed, to a program with such documented success.

Interested in lowering your risk for diabetes by joining the NDPP?

With over 625 organizations offering the program nationally, C.D.C. recognized programs are listed on the C.D.C. website at: https://nccd.cdc.gov/DDT_DPRP/Registry.aspx