Prediabetes in Teens Can Triple Risk of Premature Heart Damage: Study

Even healthy teens and young adults may be on the path to heart disease if they have high blood sugar. Simple lifestyle changes can help reduce the risk.

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Doctors know that heart disease is one of the possible complications of diabetes. However, for the first time, research has examined the earliest connection between blood sugar and the heart. A recent study found that persistently high blood sugar levels during the growth period between adolescence and young adulthood can triple the risk of structural and functional heart damage. Girls were affected at five times the rate of boys.

The findings indicate that lifestyle and dietary factors are critically important in managing blood sugar levels during this time.

How High Blood Sugar Harms the Heart

In the study, published in Diabetes Care, international researchers assessed 1,595 UK adolescents at age 17 and age 24, monitoring the prevalence of prediabetes through fasting blood sugar levels. Prediabetes refers to fasting blood sugar that is higher than normal but lower than the level that indicates a diabetes diagnosis. The blood sugar cutoff points that denoted prediabetes were 5.6 millimoles per liter (mmol/L), as recommended by the American Diabetes Association, and 6.1 mmol/L, the current recommendation in many countries.

Results showed that 6.2 percent of the adolescents at age 17 had fasting blood glucose at or above 5.6 mmol/L, which rose to 26.9 percent by age 24. Approximately 1 percent of the adolescents had fasting blood sugar at or above 6.1 mmol/L at age 17, but the prevalence rose to 5.6 percent by age 24. For both cutoff points, the difference between age 17 and age 24 represented a fivefold increase.

The research team also assessed changes in heart size by evaluating left ventricular enlargement using echocardiography, an imaging test that assesses heart structure and function. The left ventricle is the heart chamber that receives oxygenated blood from the lungs via the left atrium and pumps it to the rest of the body through the aorta. Left ventricular hypertrophy refers to thickening of the left ventricular wall, which can result in cardiac disease such as heart failure or abnormal heartbeats (arrhythmias).

Prevalence of left ventricle enlargement rose from 2.4 percent at age 17 to 7.1 percent at age 24. Heart dysfunction prevalence increased from 9.2 percent in adolescence to 15.8 percent in young adulthood. High blood glucose was also associated with decreased heart muscle relaxation, altered heart function, and increased pressure in the blood flow returning to the heart.

The measurements at ages 17 and 24 showed that fasting blood sugar at or above 5.6 mmol/L was linked to a 46 percent increase in left ventricular enlargement. Additionally, persistent insulin resistance was linked to a 10 percent rise in the likelihood of premature and worsening heart damage. Insulin resistance occurs when cells no longer respond to insulin, leading to elevated blood sugar.

Interestingly, the researchers observed a very significant difference between the sexes. The increased blood glucose levels damaged female hearts five times faster than male hearts. Therefore, the authors recommended that special attention be paid to girls in terms of prevention.

The team’s earlier research suggests that late adolescence is a key period in the development of heart and metabolic disease, said Dr. Andrew Agbaje, physician and associate professor of clinical epidemiology and child health at the University of Eastern Finland, in a press release.

“The current findings further confirm that even healthy-looking adolescents and young adults who are mostly normal weight may be on a path towards cardiovascular diseases, if they have high blood glucose and insulin resistance,” he said.

Sex Differences in Heart Risk

The metabolic system of girls is different from that of boys, Agbaje told The Epoch Times. Muscle plays a major role in blood sugar metabolism, and boys have more muscle mass than girls.

Additionally, excess fat mass underlies two-thirds of the relationship between insulin resistance and heart damage, and girls have more fat mass than boys, he said.

“It is physiologic that uncontrolled sugar levels in girls have a more rapidly developing adverse effect on the heart in comparison to boys,“ he told The Epoch Times. ”Studies among adults have shown that diabetes affects the heart worse in women than men.”

Sugar and Heart Enlargement

“High blood glucose implies that the sugar does not reach the cells that need it for fuel and energy, which is likely due to insufficient insulin,” Agbaje said.

Abnormally high blood sugar can become toxic to vital organs, including the eyes, kidneys, nerves, and heart.

Heart enlargement could occur when high blood sugar pulls more water into the blood vessels by osmosis and subsequently into the heart, he said. When this happens, the heart is forced to overwork to pump more blood volume. Overworking of the heart enlarges the heart chambers and muscle wall, which makes it function less effectively. If excess blood sugar is not reduced to a normal level early, the heart may continue to enlarge and eventually fail and stop working because of long-term stress over several decades.

The study focused on a young population, and heart failure and heart attacks are rarely diagnosed at that stage, Agbaje said.

“However, left ventricle enlargement is a marker of early heart damage that has been clinically proven to predict heart diseases and death,“ he said. ”It can lead to heart attacks, heart failure, stroke, kidney and liver failure, and premature death.”

Lifestyle Changes to Prevent Prediabetes

Adolescents are at risk for prediabetes and diabetes in large part because of their lifestyles, making these modifiable risk factors that can be reversed, Dr. Raeeda Gheewala, board-certified physician in internal medicine, told The Epoch Times.

Gheewala urges routine screenings of blood sugar for early detection of prediabetes.

“This can result in prompt lifestyle interventions before a teen’s health deteriorates to full-blown diabetes,” she said.

Increase Exercise and Decrease Screen Time

Regular physical activity plays a crucial role in lowering the risk of prediabetes, Gheewala said.

“Teens should get at least 30 minutes of moderate-intensity exercise (increasing heart rate above 100 beats per minute) on five days a week,“ she told The Epoch Times. ”This can be accomplished by limiting screen time, prioritizing eight to 10 hours of sleep, and encouraging outdoor play.”

Screen time refers to time spent watching TV and playing nonactive video games on a computer or smartphone. Limiting screen time is necessary, as such activities are popular in this age group and are associated with sedentary behavior. A systematic review published in the American Journal of Preventive Medicine found that interventions to reduce screen time led to increased physical activity and improved diet- and weight-related outcomes.

The authors observed that decreased screen time reduced exposure to unhealthy food advertising and decreased snacking on junk food.

Eat a Healthy Diet

“Increasing plant-based nutrition into a teen’s daily intake can reduce the likelihood of developing chronic disease and have a lasting impact on long-term health,” Gheewala said.

Eating causes blood sugar levels to rise, prompting the body to release insulin to restore them to a normal range.

Gheewala said the glycemic index is a marker that rates food from zero to 100 in terms of its ability to raise blood sugar. White bread, white pasta, and sweets tend to have higher glycemic indices. Additionally, packaged, processed foods, with their higher salt and sugar content, also cause blood sugar to rise, so limiting these foods along with high glycemic foods will promote healthier blood sugar levels.

Gheewala noted that fiber-rich foods such as whole grains and legumes tend to have lower glycemic indices.

“These whole foods will not only help with satiety, making teens feel full longer, but they also help with portion control and promote a healthy weight,“ she said. ”Obesity, especially obesity in the trunk, is a risk factor for prediabetes. We need to be mindful of the type and quantity of calories we ingest.”

The diet Gheewala endorses is similar to the Dietary Approaches to Stop Hypertension (DASH) diet, which consists of fruits, vegetables, whole grains, nuts, dairy, poultry, and fish. A study published in Diabetes Spectrum found that the DASH diet can improve insulin resistance and reduce obesity, making it helpful for people with prediabetes. The DASH diet was also associated with a 20 percent reduction in the risk of developing Type 2 diabetes.

Although the DASH diet is rich in plant foods, such as those in the plant-based diet Gheewala recommends, it also includes poultry and fish. Still, because the DASH diet is considered very healthy, she feels comfortable endorsing it. Gheewala noted that the goal is for people to find a healthy diet they enjoy and can maintain in the long term.

“If adding fish and poultry will allow more flexibility and variety that makes it easier to create long-term health habits, I’m all for it,“ she said. ”Small, consistent steps can have a huge return on investment.”