How Does Blood Sugar Impact Heart Rate?

blood sugar and heart
12 December, 2024

Your blood sugar level is directly related to your heart health and can impact how the organ functions. With changes in blood sugar, heart rate might also increase or decrease. Hence, maintaining the right blood sugar level is important. Abnormal blood sugar can also affect the nervous system, cause stress and even contribute to cardiovascular complications. 

This blog covers all you need to know about the link between blood sugar levels and heart rate and how it can help you lead a healthier life. 

What is Blood Sugar? 

Blood sugar is described as the level of glucose in the blood. This glucose is derived from the food and drinks that we consume, which is also the main source of our energy. The blood sugar level generally fluctuates throughout the day. People with diabetes are more prone to experience fluctuations in blood glucose. 

The amount of blood glucose in the body is important as it can impact various factors of our health and ultimately affect our lifestyle and overall well-being. Blood sugar levels being too high or too low may be an indication of an underlying health issue.  

What Level of Blood Sugar is Dangerous?

High blood sugar levels lead to hyperglycemia, and low blood sugar levels cause hypoglycemia. 

High Blood Sugar or Hyperglycemia: 

Hyperglycemia means the blood glucose levels in the body are higher than normal. It is characterised by a fasting blood glucose level exceeding 125 mg/dL. 

This is common among people with diabetes, but it can happen otherwise. This occurs when the body can’t generate or use insulin properly. 

Symptoms of Hyperglycemia

Fatigue, Nausea, Dizziness, Increased Thirst and Frequent Urination. 

Causes of Hyperglycemia

Stress, Dehydration, Overeating, Lack of Exercise and Underlying Diseases.

Impact of High Blood Sugar

When blood sugar is high (hyperglycemia), it can lead to increased sympathetic nervous system activity. This results in an elevated heart rate as the body tries to handle the excess sugar. If high blood sugar is in a chronic state, it can damage blood vessels and nerves, contributing to heart problems like high blood pressure and heart disease.

Low Blood Sugar or Hypoglycemia

Hypoglycemia means when blood sugar levels in the body decrease lower than normal, below 70 mg/dL. 

This is a harmful condition and may require immediate action. 

Symptoms of Hypoglycemia

Fatigue, Headache, Sweating, Anxiety, Dizziness, Shaking, Hunger, Numbness on the Skin and Increased Heart Rate. 

Causes of Hypoglycemia

Diabetes, Hot and Humid Weather, Menstruation, Puberty, Higher Altitudes, Malnutrition, Alcohol Overdose and more. 

Impact of Low Blood Sugar

Conversely, when blood sugar drops too low (hypoglycemia), the body perceives this as a stress situation. In response, the adrenal glands release adrenaline (epinephrine), which can cause an increased heart rate as part of the “fight or flight” response. Hypoglycemia self-care becomes a necessity for maintaining a healthy heart rate. Emergency Hypoglycemia medication may involve high-sugar drinks, glucose tablets, food and IV infusion. 

Diabetes and Heart Disease

People with diabetes, particularly those with poorly controlled blood sugar, are at higher risk of developing heart disease. The combination of high blood sugar, high cholesterol, and high blood pressure can increase the strain on the heart and lead to a higher resting heart rate.

Autonomic Nervous System

Blood sugar imbalances can influence the autonomic nervous system. This system is responsible for controlling heart rate. Consistently unstable blood sugar can lead to abnormal heart rhythm, also known as arrhythmia, or contribute to cardiovascular complications.

The sympathetic nervous system (SNS) is a part of the autonomic nervous system, responsible for the body’s “fight or flight” response. It prepares the body for action during stressful or emergency situations. It does so by increasing heart rate, dilating the airways, and redirecting the blood flow to essential organs, among other things. The SNS helps the body respond quickly to danger or stress.

Adrenaline, also known as epinephrine, is a hormone and neurotransmitter produced by the adrenal glands. It plays a central role in the body’s fight-or-flight response. 

When activated, the sympathetic nervous stimulates the release of adrenaline into the bloodstream, which causes a variety of physiological changes such as:

  • Increased heart rate and force of heart contractions
  • Dilation of the airways to improve oxygen intake
  • Increased blood flow to muscles and brain
  • Release of glucose for quick energy

Together, the SNS and adrenaline work to help the body respond to stress and physical exertion by enhancing alertness, focus, and energy availability.

Maintaining Blood Sugar Levels for a Healthy Heart; Hyperglycemia and Hypoglycemia Supportive Care  

  • Healthy Diet: Eat a balanced diet. Limit refined sugars and processed carbs. These can cause rapid spikes in blood sugar. Opt for whole grains, vegetables, legumes, and fruits that have a low glycemic index. 
  • Fibre Intake: Increase fibre intake. Fibre helps slow down sugar absorption, stabilising blood glucose levels. Foods like oats, beans, leafy greens, and berries are great sources. 
  • Healthy Fats: Incorporate healthy fats such as avocados, nuts, and olive oil to improve heart health and help manage blood sugar. Eating smaller with an increased frequency of meals can help prevent large fluctuations in blood sugar.
  • Regular Exercise: Increase physical activity. Exercise helps your body use insulin more effectively, which results in the lowering of blood sugar levels. Aim for at least 30 minutes of moderate exercise. Incorporate both cardio and strength training. These exercises improve circulation, heart function, and help regulate blood sugar.
  • Monitor Blood Sugar Levels: Regular monitoring can help you understand how your diet, activity, and medication affect your blood sugar. This allows you to make informed adjustments and maintain stability.
  • Stay Hydrated: Drink plenty of water. Staying hydrated helps flush out excess glucose through urine, keeping blood sugar levels in check.
  • Manage Stress: Keep a check on stress. Chronic stress can raise blood sugar levels. Consider meditation, yoga, deep breathing, or mindfulness practices to reduce stress. Sleep well. Poor sleep can negatively affect blood sugar levels and heart health. 7-9 hours of sleep is necessary every night.
  • Take Medications as Prescribed: If you have diabetes or prediabetes, follow your doctor’s advice regarding medications or insulin therapy. These can help regulate blood sugar and protect heart health. Following up with hyperglycemia and hypoglycemia medication is necessary. 
  • Maintain a Healthy Weight: Being overweight increases the risk of insulin resistance. A healthy diet and the right amount of exercise can help with weight management.
  • Avoid Smoking and Moderate Alcohol: Smoking can worsen the effects of high blood sugar on the cardiovascular system. Alcohol can cause blood sugar to rise or fall unpredictably. Stick to moderate consumption and monitor how it affects your blood sugar.
  • Regular Check-ups are Necessary: See your doctor regularly. Regular visits to your healthcare provider will help monitor your heart health and blood sugar levels, allowing for timely intervention if needed.
Doctor drawing blood from a patient's arm using a needle

About Atrius Cardiac Care

At Atrius Cardiac Care, our team of expert cardiologists is dedicated to helping you achieve and maintain optimal heart health. We provide personalised guidance on managing blood sugar levels and other critical factors to keep your heart healthy. With years of experience and a patient-focused approach, we have positively transformed countless lives.

Take the first step toward a healthier heart—book your appointment with Atrius Cardiac Care today.