Managing Diabetes

New Technologies Can Make It Easier

Your body takes care of countless tasks for you. You might not notice all it’s doing to keep you healthy until something goes wrong.

Diabetes is a serious disease that happens when your body has trouble managing and using blood glucose, a sugar that your body uses as fuel. When you have diabetes, you must actively take on this process yourself. New technologies are being tested to make it easier for you to control diabetes and to help you stay healthy.

More than 100 million Americans are living with diabetes or prediabetes, a condition where blood glucose levels are higher than normal, but not high enough to be considered diabetes. People with diabetes must frequently check their blood glucose (or blood sugar) and take quick action if it gets too high or low. They must also constantly consider how all meals, physical activity, and things like stress will affect their blood glucose.

Types of Diabetes

How people with diabetes manage their blood glucose levels depends, in part, on the type of diabetes they have. The most common are type 1, type 2, and gestational diabetes.

With type 1 diabetes, your body doesn’t make enough of a hormone called insulin. Insulin signals the body’s cells to let glucose inside. The body can’t produce enough insulin because the immune system, your body’s defense against germs and foreign substances, mistakenly attacks and destroys the cells in your pancreas that make insulin.

Type 2 diabetes is the most common. It occurs when either your body’s cells have trouble using insulin or your body doesn’t produce enough insulin to handle the glucose in your blood.

Both types can develop at any age. Type 1 is most often diagnosed in children and young adults, while type 2 shows up most in middle-age and older people. Gestational diabetes occurs only during pregnancy, but increases your chances of developing type 2 later in life.

Diabetes symptoms can vary by type. Some shared symptoms include increased thirst, hunger, and urination. Symptoms of type 1 can start quickly, over a few weeks. Type 2 symptoms tend to develop slowly over years, making them less noticeable.

Blood Glucose Control

Many people with diabetes check their blood glucose with a blood glucose meter. This portable machine measures how much glucose is in the blood. You get a drop of blood by pricking the side of your fingertip with a small, specialized needle. Then you apply the blood to a test strip. The meter shows you how much glucose is in your blood at that moment.

People with type 1 diabetes, and some people with type 2, correct and manage their blood glucose with injections of synthetic insulin. A missed, or miscalculated, dose can lead to serious complications, immediately and over time. Diabetes increases your risk for blindness, heart disease, stroke, kidney failure, and amputation.

“It’s a significant burden to self-test sugar levels several times a day, count carbohydrates with each meal, take into account the impact of physical activity, and then calculate the amount of insulin you need to inject multiple times a day with a syringe or the help of an insulin pump,” explains Dr. Guillermo Arreaza-Rubín, who heads NIH’s Diabetes Technology Program. Any error in this management may lead to life-threatening complications like severe hypoglycemia, which is very low blood glucose.

“Hypoglycemia is one of the main reasons people with type 1 visit hospital emergency rooms every day,” Arreaza-Rubín says. “It happens more frequently during the night and is a major cause of fear and anxiety among people with diabetes and their families.”

Help From Technology

NIH funded-scientists are testing promising technologies to help people better manage diabetes. For example, “artificial pancreas” systems monitor blood glucose levels and provide insulin, or a combination of insulin and another important hormone, automatically. The devices vary in how easy they are to set up and use.

“Our device, called the iLet, is designed to minimize the guesswork and time drain that comes with managing type 1 diabetes,” says Dr. Edward Damiano, a biomedical engineering expert at Boston University who’s co-founded a company to further develop the technology. The device only requires that you type in your body weight to get started. “The system does the heavy lifting of regulating blood glucose, freeing up the user to live a less burdened and more spontaneous life.”

Previous studies have shown that artificial pancreas systems can be safer than the current standard for insulin delivery. Several different devices are now being tested in more people for longer periods of time. Researchers are looking at safety, user-friendliness, the physical and emotional health of the participants, and cost.

Safety is a priority for researchers. “When people with type 1 exercise, their blood glucose can respond in unpredictable and potentially dangerous ways,” explains University of Virginia engineer Dr. Marc Breton. He led a recent study that showed an artificial pancreas system improved glycemic control and reduced hypoglycemia in adolescents with type 1 diabetes as they participated in winter sports, like skiing and snowboarding.

“The artificial pancreas performed very well in an extremely challenging environment,” he says. “Eventually, it may allow people with diabetes the freedom to participate safely in physical activities that they likely avoided in the past.”

One FDA-approved artificial pancreas is already available for people with diabetes. Devices that are more fully automated may become available to the public within the next couple years. Researchers are considering how to use these systems for people with type 2, gestational diabetes, and other conditions involving elevated blood glucose levels.

Other scientists are taking different approaches to replace insulin more effectively. For example, “smart insulins” would become active only when needed. Researchers are also looking for ways to regenerate or replace insulin-producing cells—and to stop the body from attacking them.

“These technologies will help make managing diabetes easier and will help make people who use them healthier,” says Damiano. “I see them as a bridge to a cure for type 1 diabetes.”

While future tools may make it easier to manage your diabetes, you can learn how to manage diabetes with the tools we have now to live a long, healthy life. Medications, glucose monitors, and insulin pumps are all available now to help people with diabetes. If you have diabetes, talk with your health care provider about your options.

Preventing Type 2 Diabetes

Steps Toward a Healthier Life

People with diabetes have a problem with blood sugar. Their blood sugar, or blood glucose, can climb too high. Having high levels of sugar in your blood can cause a lot of trouble. Diabetes raises your risk for heart disease, blindness, amputations, and other serious issues. But the most common type of diabetes, called type 2 diabetes, can be prevented or delayed if you know what steps to take.

About 29 million Americans, or nearly 1 in 10 people, have diabetes. Many more have a condition called prediabetes. People with prediabetes usually have no symptoms, yet they’re at risk for eventually developing type 2 diabetes, heart disease, and stroke.

Research shows that you can greatly reduce your risk for type 2 diabetes and prediabetes by eating a healthy diet, getting plenty of physical activity, and losing excess weight.

Type 2 diabetes arises because of problems related to a hormone called insulin. When our bodies digest the foods we eat, they’re broken down and converted to glucose and other molecules, which then travel through the bloodstream. Insulin signals cells to let glucose in for use as an energy source. When a person has type 2 diabetes, either the body’s cells have trouble using insulin, or the body isn’t producing enough insulin. As a result, glucose can build up to harmful levels in the blood.

Type 2 diabetes occurs most often in people who are middle-aged or older, but younger people can get it too. “Before the mid- to late-1990s, we almost never saw type 2 diabetes in youth,” says Dr. Barbara Linder, an NIH expert on childhood diabetes. But now, type 2 diabetes is becoming more common in young people, alongside increasing rates of childhood obesity.

Some factors that raise people’s risk for type 2 diabetes are beyond their control. Having an immediate family member with diabetes increases your risk. Type 2 diabetes is also more common in some races or ethnicities, including African-Americans, Alaska Natives, American Indians, Asian-Americans, Pacific Islanders, and Hispanic/Latinos.

People who are overweight, obese, or inactive are also much likelier to develop type 2 diabetes. But these are risk factors that you can change, and doing so will greatly reduce your risk for diabetes.

To understand how weight loss might affect diabetes risk, NIH launched a study in the early 1990s called the Diabetes Prevention Program. Doctors already knew that being overweight or obese was a risk factor for diabetes, but they didn’t know if losing weight would reduce that risk.

The study enrolled more than 3,000 people who were overweight and had prediabetes. They were randomly assigned to different groups.

One group met regularly with study staff to focus on healthy behaviors, such as eating fewer calories and exercising more; they aimed to lose at least 7% of their body weight and to do at least 150 minutes of physical activity per week. Another group received metformin, a drug commonly used to treat type 2 diabetes, along with standard advice on diet and exercise. A control group received standard advice and an inactive placebo pill, which had no drug effects.

After an average of around 3 years, the researchers found that diabetes risk dropped by 58% in the group encouraged to make healthy lifestyle changes. About 38% in that group had achieved and maintained their weight loss goals and 58% their physical activity goals. The group taking metformin was also less likely to develop diabetes; their risk dropped by 31% compared to the control group.

In a follow-up study, both lifestyle changes and metformin continued to reduce the risk of developing diabetes, although their effects declined. After 10 years, people who continued with lifestyle changes delayed diabetes by about 4 years compared to people in the control group. People who continued to take metformin delayed diabetes by about 2 years.

Metformin has long been used and approved for treating type 2 diabetes. However, the U.S. Food and Drug Administration hasn’t approved the drug for preventing type 2 diabetes. Research suggests that the drug’s preventive effects may work best in younger and heavier people. For older people, lifestyle changes were especially helpful; they lowered diabetes risk by 71%.

“Weight loss is key, and physical activity is very important, but lifestyle changes are never easy,” says NIH’s Joanne Gallivan, director of the National Diabetes Education Program (ndep.nih.gov). The program offers resources to help with weight loss, healthy eating, and physical activity. Specific tips are provided for certain groups of people, such as children and older adults. Most materials are offered in Spanish, and some are available in other languages.

As the Diabetes Prevention Program showed, diet and exercise can reduce the risk of developing type 2 diabetes. You’re most likely to succeed at weight loss, Linder says, “if you can find some physical activity that you enjoy and can do every day.”

To lose weight, you need to burn more calories than you consume. Participants in the Diabetes Prevention Program followed a low-fat, low-calorie diet. Experts now recognize that different people may need different diets. “If you’re eating a lot of fat, that’s what you need to cut out. If you’re eating a lot of candy, then that’s what you need to cut,” Linder says. “You have to individualize it.”

Experts recommend that people at risk for type 2 diabetes should exercise weekly at moderate intensity for 150 minutes. That’s 30 minutes, 5 times a week.

“Get your heart rate up a bit. Work up a mild sweat,” says Harvard’s Dr. David Nathan, who leads the Diabetes Prevention Program studies. The training program used in the study is now widely available; for instance, the YMCA now offers a program based on the study.

If you think you might have prediabetes or diabetes, your doctor can help you decide what to do. A blood test called the A1C test can check your average blood glucose level to see if you have prediabetes.

Nathan says that people over 45 should be screened for diabetes, as should other people at increased risk. Risk factors and warning signs for type 2 diabetes include high blood pressure, high cholesterol, or a history of gestational diabetes or cardiovascular disease.

In 2012, 1.7 million Americans ages 20 and older were newly diagnosed with diabetes. “That’s not good, but it’s actually less than the 1.9 million new cases we had in 2010,” Nathan says. “It may just be that we are turning the corner a little bit.”

Feeling Stressed?

Stress Relief Might Help Your Health

Winter holidays—do they fill you with joy or with worries about gift-giving and family gatherings? Do summer vacations leave you relaxed or fretful over travel and money? If you’re feeling stressed out over supposedly fun things, it might be time to reassess. Take a few moments to learn how stress affects your health and what you can do about it.

Everyone feels stressed from time to time. Stress can give you a rush of energy when it’s needed most—for instance, competing in sports, working on an important project, or facing a dangerous situation. The hormones and other chemicals released when under stress prepare you for action. You breathe faster, your heartbeat quickens, blood sugar rises to give you energy, and your brain uses more oxygen as it shifts into high alert.

But if stress lasts a long time—a condition known as chronic stress—those “high-alert” changes become harmful rather than helpful. “Stress clearly promotes higher levels of inflammation, which is thought to contribute to many diseases of aging. Inflammation has been linked to cardiovascular disease, diabetes, arthritis, frailty, and functional decline,” says Dr. Janice Kiecolt-Glaser, a leading stress researcher at Ohio State University. She and other researchers have found that stress affects the body’s immune system, which then weakens your response to vaccines and impairs wound healing.

Research has linked chronic stress to digestive disorders, urinary problems, headaches, sleep difficulties, depression, and anxiety.

“Some studies have found the physical, emotional, and social effects of a disease like cancer to be stressful for patients, caregivers, and long-term cancer survivors,” says NIH’s Dr. Paige Green McDonald, an expert on stress and cancer biology. “However, there’s no definitive evidence that stress causes cancer or is associated with how long one survives after a cancer diagnosis.”

The top causes of stress in the U.S. are money and work-related pressures, according to a 2013 survey from the American Psychological Association. Stress can also arise from major life changes, such as the death of a loved one, divorce, illness, or losing a job. Traumatic stress is brought on by an extreme event such as a major accident, exposure to violence, or a natural disaster such as a hurricane or flood.

Caring for a person with severe illness—such as dementia or cancer—can also be a significant source of stress. More than a decade ago, studies by Kiecolt-Glaser and others showed that the stressful demands placed on caregivers can lead to poorer health, lower responses to vaccines, increased inflammation, and a more than 60% higher death rate compared to non-caregivers.

It’s not clear why some people can sidestep or recover more quickly from stress than others. These resilient people seem to “bounce back” more easily after stressful situations. Recent studies of animals suggest that resiliency may depend at least in part on our genes. But learning healthy ways to cope with stress can also boost your resilience.

“There are many different ways to cope with stress. We know from a lot of different studies that having close personal relationships—people with whom you can talk, with whom you can share your feelings—can be helpful,” says Kiecolt-Glaser. “So spending time with family and friends in order to maintain those relationships is perhaps one of the most crucial things you can do as a stress reducer.”

Unfortunately, Kiecolt-Glaser adds, “when we’re stressed, we tend to do the worst things that are not at all helpful to our health.”

For instance, stressed out people may tend to isolate themselves and not seek social support. “Exercise is a great stress reducer. But when people are stressed, exercise becomes less common and less appealing,” Kiecolt-Glaser says. “Instead of maintaining a healthy diet—also important to reducing stress—some people who are stressed tend to eat more donuts than vegetables.”

You may think that the agitation brought on by stress might help to burn calories. But evidence hints that the opposite is more likely. Kiecolt-Glaser and colleagues found that, compared to nonstressed people, those who were stressed burned fewer calories after high-fat meals and they produced more of the hormone insulin, which enhances fat storage. “So stress may contribute to weight gain and obesity through these biological routes,” Kiecolt-Glaser adds.

Getting enough sleep is also key to resilience and stress relief—although stress itself can interfere with sleep. To improve your sleep habits, go to bed the same time each night and get up the same time each morning, and limit the use of light-emitting electronics like computers and smartphones before bed. The light can reduce production of a natural sleep hormone called melatonin, which then makes it hard to fall asleep.

Beyond recommendations for exercise, healthy diet, social contacts, and getting enough sleep, Green McDonald says, “studies have also shown that mindfulness (focused attention on one’s own emotions) and other meditative practices can effectively relieve stress.”

“Mindfulness means staying aware and conscious of your experiences. No matter what we’re doing, we can always make time to bring our attention to our breath and body and stay there for a short period of time,” says NIH psychologist Dr. Rezvan Ameli, who specializes in mindfulness practice. “Recent studies show that even short periods of mindful attention can have a positive impact on health and well-being.”

Other NIH-funded studies have shown that mindfulness meditation can reduce stress, alter brain structure and function, and have a positive effect on the immune system.

“Mindfulness is a simple and effective tool that anybody can use to reduce stress,” Ameli says. Although the concept is simple, becoming more mindful requires commitment and practice. You can learn more about mindfulness meditation from local resources like yoga or meditation classes, mindfulness-based stress-reduction programs, or books.

If you feel overwhelmed by stress, talk with a health care provider or mental health professional. Medications or other therapies might help you cope. In the long run, reducing stress may help you to slow down and enjoy your time with the people and activities you really care about.

Opportunities Abound for Moving Around

Get Active, Wherever You Are

You know that physical activity can help you live a longer, healthier life. But did you know you don’t need to join a gym or use costly equipment to be physically active? No matter where you live, work, or go to school, you can find ways to move more and sit less throughout your day. In addition to helping your health, you might have fun without spending a lot of money.

Moving more and sitting less can reduce your risk for many serious conditions, including heart disease, diabetes, osteoporosis, and certain kinds of cancer. Some studies suggest that physical activity can have mental benefits as well, helping to relieve depression and maintain thinking abilities as you age. Healthful physical activity includes exercise as well as many everyday activities, such as doing active chores around the house, yard work, or walking the dog.

Activities that cause you to breathe harder are called aerobic activities. These make your heart and blood vessels healthier. Aerobic activities include brisk walking, dancing, swimming, and playing basketball. Strengthening activities, like push-ups and lifting weights, help make your muscles and bones stronger and can also improve your balance.

But even though many of us know that physical activity is a good thing, most adults nationwide don’t meet even the minimum recommended amounts of physical activity. (That’s at least 30 minutes of brisk walking or other moderate activity, 5 days a week.)

Why aren’t we more active? “Lack of time is a common reason for not exercising,” says Dr. Mary Evans, an NIH expert on physical activity and nutrition. “Another important factor is location—having safe places to walk and engage in different activities. That can mean having sidewalks, public parks with well-lit walking paths, a shopping mall where you can walk, or other features that can make activity inviting and easy to do.”

NIH-funded research has found that your environment—where you live, work, or go to school—can have a big impact on how much you move and even how much you weigh.

Some communities don’t have safe playgrounds or sidewalks, so kids tend to spend their free time indoors. Sitting instead of moving makes it hard to maintain a healthy weight. Many adults sit behind the wheel driving to work and then sit most of the day at a computer, taking few breaks to stand up and move around. In suburban neighborhoods, people often have to drive rather than walk to get to grocery stores, shops, and even public transportation.

“Our environments have become less friendly to being active. But studies show that people will walk more if the environment provides them with opportunities to do so,” says Dr. Brian E. Saelens, a health psychologist and behavioral scientist at the University of Washington in Seattle. “How close are you to a library? Can you walk to a store? Is there a safe path for walking to school? All of these factors affect how active we are each day.”

Having places to walk and have fun can help more people get moving and active. “It’s not just dangerous neighborhoods, broken streets, and crime that can keep people indoors and away from being physically active,” says Dr. Allen Glicksman, director of research at the Philadelphia Corporation for Aging. “We’ve also found that, from ages 18 to 80, if a neighborhood has someplace nice to walk to—desirable destinations like a book store, grocery store, coffee shop, a place to eat or meet—it can have a healthful effect on how much people weigh and how much they walk.”

Research also shows that taking public transportation—like buses and trains—can help boost activity. In a recent Seattle-area study, Saelens and colleagues found that people tend to add about 15 minutes of activity to their day when they take public transportation, in part by walking to and from the mass transit site instead of taking a car from door to door. “That’s half the recommended amount of physical activity added to their day,” Saelens says.

Having opportunities to connect with others can also have a positive effect. “Many people are more likely to walk if they’ve got one or more buddies to walk with,” Glicksman says. “When you think about what brings people together, what brings people out and active, the answer can vary depending on your community.” In urban Philadelphia, Glicksman and others have found that neighborhood features like access to public transportation, better bus shelters, and even murals in some neighborhoods seem to encourage more physical activity.

When community gardens were created for older adults in Philadelphia, Glicksman says, “we wanted people to garden to help them eat fresh foods and get them out and moving in the nice weather.” When younger adults joined in as well, the gardens had the added bonus of connecting people across generations. The older adults acted as gardening mentors, while the younger people helped with heavy lifting and digging. “Bringing people together is not only a way to encourage more activity; it’s also a way to get people thinking about how we can change our neighborhoods for the good.”

So take a look around your neighborhood, your workplace, or your school. Can you think of changes that might make the surroundings more inviting for walking or exercise?

“Consider: How can we change our environment so activity is an easier choice for us to make?” Saelens says. In many communities, people have gotten together to organize activities and improve their environments to encourage more physical activity. Steps might include improving local parks, requesting safe and usable bike paths and sidewalks, or asking for more physical activity and healthier meals at schools. If you have some ideas for improving your surroundings, discuss them with your neighbors or local leaders.

Although your environment can affect how active you are, you can still look for new ways to use the world around you to add some movement to your day.

“If you’re at work, try climbing the stairs instead of using the elevator. And get up from your chair and move around at least once an hour,” Evans says. Stand up and walk to a colleague’s office instead of sending an email. Try standing instead of sitting when you’re on the phone, or have “walking” meetings with co-workers instead of sitting in a conference room. And take a brisk walk on your lunch break to get some activity in.

“It’s not really necessary to engage in vigorous physical activity like running to have beneficial health effects. Just 30 minutes of brisk walking most days, in at least 10-minute segments, can have a positive effect,” Evans says.

“We have to look for opportunities to fit physical activity into our days,” Saelens adds. “Some people love to put on their sneakers and to go to the gym, and that’s great for them, but it’s not the only way to get active.”

How Your Eating Habits Affect Your Health

A healthy eating plan lowers your risk for heart disease and other health conditions. m-imagephotography/iStock/Thinkstock

A new study shows how the things you eat can influence your risk of dying from heart disease, stroke, or type 2 diabetes. The findings suggest ways to change your eating habits to improve your health.

Experts already know that a healthy eating plan includes vegetables, fruits, whole grains, and fat-free or low-fat dairy products. A healthy diet also includes lean meats, poultry, fish, beans, eggs, and nuts. It limits saturated and trans fats, sodium, and added sugars.

NIH-funded scientists analyzed how these 10 dietary factors affect your risk of death from heart disease, stroke, and type 2 diabetes. These are known as cardiometabolic diseases. The team relied on data from the CDC’s National Health and Nutrition Examination Survey (NHANES) and national mortality data.

The scientists found that risk of death from the 3 diseases was higher for those who consumed too much sodium, processed meat, sugar-sweetened beverages, and unprocessed red meat. Risk of death was also higher among those who didn’t eat enough nuts and seeds, seafood omega-3 fats, vegetables, fruits, whole grains, or polyunsaturated fats. According to the analysis, nearly half (45%) of deaths in 2012 from the 3 diseases was associated with too much or too little of these 10 dietary factors.

“This study establishes the number of cardiometabolic deaths that can be linked to Americans’ eating habits, and the number is large,” explains Dr. David Goff, a heart disease and public health expert at NIH. “Second, it shows how recent reductions in those deaths relate to improvements in diet, and this relationship is strong. There is much work to be done in preventing heart disease, but we also know that better dietary habits can improve our health quickly, and we can act on that knowledge by making and building on small changes that add up over time.”

Cone Snail Venom Reveals Insulin Insights

A marine cone snail hunting a fish. Photo courtesy of Dr. Baldomero Olivera, University of Utah

The marine cone snail has an unusual survival mechanism that offers new insights for managing diabetes. The snail releases an insulin-containing venom that acts within seconds to stun nearby fish, so they’re easier to capture and eat. Scientists have been fascinated by how rapidly this insulin works compared to human insulin.

Insulin is important for people because it helps maintain blood sugar (glucose) levels. When glucose levels rise, such as after a meal, insulin is released into the bloodstream and travels throughout the body. When insulin binds to special cell-surface structures called receptors, it triggers cells to take in the glucose needed for energy. Diabetes arises when this process doesn’t work correctly. Many people rely on injections of synthetic insulin to manage their diabetes, and rapid action can be crucial.

Human insulin is stored in the body in clusters of 6. To work, the 6 parts must first separate, which might take up to an hour. In contrast, the insulin in cone snails is small and fast acting. It lacks the portion that would hold insulin clusters together.

An NIH-supported research team, based partly at the University of Utah, analyzed the 3-D structure of cone snail insulin. Despite its smaller structure, the snail insulin could bind and turn on the human insulin receptor.

We found that cone snail venom insulins work faster than human insulins by avoiding the structural changes that human insulins undergo in order to function—they are essentially primed and ready to bind to their receptors,” says study coauthor Dr. Michael Lawrence of the Walter and Eliza Hall Institute of Medical Research in Australia.

These findings provide insights that could help scientists design rapid-acting insulins that might help to manage diabetes.

Think Twice Before Eating White Rice?

Eating more white rice raised the risk for type 2 diabetes in a large clinical study, whereas eating more brown rice reduced the risk.

Type 2 diabetes is one of the fastest growing health problems in Americans of all ages. Being overweight or inactive increases your chances of developing the disease. Research suggests that eating more refined foods, including white bread and sugary foods, might also raise the risk.

The new study followed about 200,000 people for up to 22 years. The people who ate at least 5 weekly servings of white rice had a 17% higher risk than those who ate less than 1 serving per month.

On the other hand, people who ate at least 2 servings of brown rice a week had an 11% lower risk of developing type 2 diabetes than those who ate less than 1 serving a month.

“We believe replacing white rice and other refined grains with whole grains, including brown rice, would help lower the risk of type 2 diabetes,” says study co-author Dr. Qi Sun of Brigham and Women’s Hospital in Boston.

Healthy Body, Happy Heart

Improve Your Heart Health

Every moment of the day, your heart is pumping blood throughout your body. In silent moments, you can hear the thump-thump-thump of its demanding work. Do you take your heart for granted? Most of us will have heart trouble at some point in our lives. Heart disease is the number one killer of women and men in the United States. But you can take steps now to lower your risk.

“About 1 out of 3 people in America will die of heart disease,” says NIH heart disease expert Dr. David C. Goff, Jr. “And about 6 out of every 10 of us will have a major heart disease event before we die.”

Heart disease develops when the blood vessels supplying the heart become clogged with fatty deposits, or plaque. After the blood vessels narrow, blood flow to the heart is reduced. That means oxygen and nutrients can’t get to the heart as easily.

Eventually, an area of plaque can break open. This may cause a blood clot to form on the plaque’s surface. A blood clot can block blood flowing to the heart. That can cause a heart attack.

A heart attack happens when a vessel supplying the heart is blocked and the heart can’t get enough oxygen, which leads to death of heart muscle.

The three major risk factors for heart disease have been known since the 1960s: smoking, high blood pressure, and high cholesterol levels. These were identified in NIH’s Framingham Heart Study, a long-term study of people in Framingham, Massachusetts.

“If we could eliminate cigarette smoking, elevated blood pressure, and elevated cholesterol levels, we could eradicate about 9 out of 10 heart attacks in our country,” says Dr. Daniel Levy, a heart specialist at NIH who oversees the Framingham Heart Study currently.

The study has also uncovered other risk factors, including diabetes, obesity, and physical inactivity. Levy’s research team is now hunting for genes that may be risk factors for heart disease. By understanding the factors that play a role in heart disease, scientists hope to find new ways to prevent and treat it.

Get Tested

Early heart disease may not cause any symptoms. That’s why regular checkups with your doctor are so important.

“The sad truth is that the vast majority of us has heart disease and we don’t know it,” Goff says.

Blood pressure and cholesterol levels can provide early signs. “People should see their doctor, find out their cholesterol and blood pressure numbers, and if needed, take medication,” advises Goff.

There are many other tests to detect heart disease. An electro-cardiogram, also called an EKG or ECG, measures electrical activity in your heart. It can show how well your heart is working and pick up signs of a previous heart attack.

Another test called an echocardiogram uses sound waves to detect problems. It shows the size, shape, and structures of your heart. It can also measure blood flow through your heart.

Although early heart disease might not cause symptoms, advanced heart disease may cause chest pressure, shortness of breath, or fatigue. Some people may feel lightheaded, dizzy, or confused. Tell your doctor if you’re experiencing any symptoms.

Make Healthy Choices

Talk with your doctor about your risk of heart disease and what you can do to keep your heart healthy.

“The most important things for everyone to do to keep their heart healthy—to keep their entire body healthy—is to eat a healthy diet, get plenty of physical activity, maintain a lean body weight, and avoid smoking and exposure to secondhand smoke,” Goff says.

Following a heart-healthy eating plan is important for everyone. “When someone puts food on their plate, about half the plate should be fruits and vegetables. About a quarter of the plate should be whole grain. And about a quarter should be lean protein, like lean meat or seafood,” says Goff.

If you have high blood pressure, you may want to follow the DASH (Dietary Approaches to Stop Hypertension) diet. This diet emphasizes fruits, vegetables, whole-grain foods, and low-fat dairy products. To learn more about the diet, see www.nhlbi.nih.gov/health/health-topics/topics/dash.

Goff also advises, “Avoid foods that have a lot of salt in them. Salt is a major contributor to high blood pressure and risk of heart disease.”

Prevent Diabetes

Diabetes increases your chances of high blood pressure and high cholesterol. You’re also more likely to develop heart disease and have a heart attack.

“Having diabetes is almost like already having heart disease,” says Dr. Larissa Avilés-Santa, a diabetes and heart health expert at NIH. She oversees a large NIH study of heart disease risk factors among more than 16,000 Hispanic/Latino adults.

Avilés-Santa says that sometimes people think that they will develop diabetes and heart disease no matter what they do. But that’s not true. Even if you have a family history of these diseases, you can be the messenger of good health for your family, she says. You can help your family by inspiring healthy habits.

The best way to prevent diabetes is through diet and physical activity. “The evidence is outstanding that very modest changes in lifestyle could reduce the risk of developing diabetes much greater than medication,” Avilés-Santa says.

Get Help

For some people, having a heart attack is the first sign of heart disease. Pain or discomfort in your chest or upper body, a cold sweat, or shortness of breath are all signs of a heart attack.

If you feel any of these signs, get medical help right away. Acting fast can save your life and prevent permanent damage.

Heart disease and heart attacks are major risk factors for cardiac arrest, which is when the heart suddenly stops beating. Blood stops flowing to the brain and other parts of the body. If not treated within minutes, cardiac arrest can lead to death.

Heart disease and heart attacks can also make it harder for your heart’s electrical system to work. As a result, an irregular heartbeat, or arrhythmia, can occur. Your heart may beat too fast, too slow, or with an uneven rhythm. A dangerous arrhythmia can lead to cardiac arrest.

Regular checkups help ensure that a doctor will check your heart for problems. Heart disease and arrhythmias can be treated to lower the risk of cardiac arrest.

Be good to your heart. Don’t take it for granted. Get tested for heart disease, and follow your doctor’s suggestions. See the sidebar for questions you may want to ask your doctor.

Diabetes and Risk for Heart Disease and Stroke

Having type 2 diabetes increases the risk of cardiovascular events, like stroke or heart attack. For nearly a decade, NIH has supported a large clinical trial called the ACCORD study. It aimed to find ways to reduce the likelihood of cardiovascular events in adults with type 2 diabetes who are at especially high risk because of a previous heart attack, stroke or other reason.

One ACCORD trial involved more than 4,700 people who had diabetes and high blood pressure. They were asked to control their blood pressure with medications. Some were asked to target a standard blood pressure level, while others aimed for a lower level that’s considered normal in healthy people.

Lowering blood pressure to normal levels didn’t significantly reduce the risk of cardiovascular events overall. However, it did appear to reduce the likelihood of stroke.

Another report looked at 5,500 patients to evaluate a combination of 2 types of drugs that can reduce blood levels of fatty molecules called lipids. A statin medication alone proved as beneficial as a combination of a statin and a fibrate medication.

“Although our analysis suggests that certain patients may benefit from combination therapy, this study provides important information that should spare many people with diabetes unneeded therapy with fibrates,” says Dr. Henry Ginsberg of Columbia University, who led ACCORD’s lipid trial.