Type 2 Diabetes Prevention and Management
What is Type 2 Diabetes?
Type 2 diabetes is a chronic metabolic disorder characterised by high blood sugar levels due to insulin resistance and/or insufficient insulin production. Regular physical activity and a healthy diet improves insulin sensitivity, lower blood sugar levels, and reduce the risk of complications associated with type 2 diabetes.
Type 2 Diabetes and Exercise Physiology:
The hormonal and physiological changes that occur when someone with diabetes performs exercise are complex and involve various mechanisms within the body. It is not as simple as using more blood sugar. Understanding these changes requires knowledge of several key scientific concepts related to exercise physiology and diabetes.
Some of the main factors at play are:
Insulin Sensitivity: Exercise can improve insulin sensitivity. When you exercise, your muscles require more glucose for energy. To meet this demand, the body becomes more responsive to insulin, allowing it to transport glucose from the bloodstream into the muscle cells more effectively. This is particularly important for individuals with type 2 diabetes, as they often have reduced insulin sensitivity.
Glucose Uptake: During exercise, muscles can take up glucose without the need for insulin. This process is mediated by a protein called GLUT4, which is translocated to the muscle cell membrane when the muscles contract. This allows glucose to enter muscle cells and be used for energy.
Hormonal Responses:
Epinephrine and Norepinephrine: Exercise triggers the release of these stress hormones, which can stimulate the liver to release glucose into the bloodstream. This helps maintain blood sugar levels during exercise.
Glucagon: This hormone is released by the pancreas to stimulate the liver to release glucose when blood sugar levels drop. Exercise can temporarily increase glucagon levels.
Catecholamines: Exercise leads to an increase in catecholamines like epinephrine and norepinephrine. These hormones can increase heart rate, raise blood pressure, and mobilise energy stores, including glycogen and fat.
Muscle Contraction: Muscle contractions during exercise, especially resistance training, can have an immediate impact on glucose uptake and utilisation. These contractions activate glucose transporters and promote the use of stored glycogen for energy.
Post-exercise Glucose Control: After exercise, glucose uptake by muscles continues for several hours, especially if the exercise was intense. This can help lower blood sugar levels in the post-exercise period.
Lactic Acid Production: During intense exercise, muscles may produce lactic acid, which can increase blood acidity. The body responds by releasing bicarbonate ions and increasing respiration, which can affect the acid-base balance in the body.
Blood Flow: Exercise can increase blood flow to the muscles, helping to deliver oxygen and glucose to the cells and remove waste products. This enhanced circulation is important for people with diabetes as it promotes overall metabolic health.
Stress Response: In response to the stress of exercise, the body can release cortisol, which may increase blood sugar levels. However, the effect is typically temporary, and the long-term benefits of regular exercise usually outweigh this short-term increase.
It is important that your Exercise Physiologist understands this above information in order to prescribe appropriate exercise. In addition to understanding the physiology of diabetes and exercise dose and response, here's how an exercise physiologist can directly assist individuals with type 2 diabetes:
Assessing individual needs: The first step is to assess the specific needs and limitations of the person with type 2 diabetes. This assessment includes considering current fitness levels, medical history, any complications related to diabetes, and individual goals.
Creating tailored exercise plans: Based on the assessment, we then develop a personalised exercise plan. This plan will consider the person's fitness level and preferences while also considering any contraindications or limitations, including other conditions or injuries. The goal is to create a plan that is safe, effective, and will be adhered to.
Monitoring and adapting exercise routines: We will closely monitor the individual's progress and adjust the exercise program as necessary. This adaptation can help ensure that the exercise regimen remains challenging and effective over time.
Educating on diabetes management: In addition to exercise guidance, we educate individuals about the relationship between exercise and diabetes management. We may explain how exercise affects blood sugar levels, insulin sensitivity, and overall health. This knowledge empowers individuals to make informed choices about their exercise routines and dietary habits.
Promoting lifestyle changes: Our exercise physiologists collaborate with our registered dietitians and the endocrinologist, to create a comprehensive approach to managing type 2 diabetes. Lifestyle changes may include dietary modifications, stress management, and medication management, in addition to exercise.
Providing motivation and support: Staying motivated to exercise regularly can be challenging for many people. We offer motivation and support to help individuals stick to their exercise routines, set achievable goals, and celebrate progress.
Reducing the risk of complications: Regular exercise can help reduce the risk of complications associated with type 2 diabetes, such as cardiovascular disease, nerve damage, and kidney problems. We minimise these risks through appropriate exercise and lifestyle choices.
Collaborating with healthcare teams: We often work as part of a healthcare team to ensure a holistic approach to diabetes management. We may communicate with GP’s and other specialists to provide the best possible care for the individual.
Overall, our exercise physiologists play a vital role in helping people with type 2 diabetes incorporate exercise into their daily lives safely and effectively. Personalised guidance and ongoing support contribute to improved blood sugar control and better overall health for individuals with diabetes.
Type 2 Diabetes and Dietetics:
The hormonal and physiological changes that occur when someone with type 2 diabetes eats food containing carbohydrates are complex and involve various mechanisms within the body. It is not as simple as all carbohydrate foods are made equally. Understanding these differences requires knowledge of several key scientific concepts related to food and diabetes and is essential for managing blood glucose levels.
Some of the main factors at play are:
Insulin Resistance: Insulin resistance is when cells throughout the body (muscles, fat and liver) no longer respond as well to insulin as they have previously done. When this occurs, cells cannot easily take up glucose from the blood and therefore the glucose remains high in the blood causing high blood glucose levels. As a result, the pancreas is triggered to make more and more insulin to help glucose enter the cells. Insulin resistance is caused by excessive weight, in particular visceral fat which is an accumulation of fat around the midsection (abdomen) and a lack of physical activity.
Hormonal Responses: Insulin is a hormone released by a section of the pancreas known as the islets of Langerhans. Located here are the beta cells which are responsible for insulin secretion. Insulin is released in response to elevated levels of glucose in the blood. When insulin levels are chronically high in the body it is known as hyperinsulinemia and this has detrimental effects on the body including obesity, type 2 diabetes, cardiovascular disease and a decrease in health span and life expectancy. One major function of insulin as an anabolic hormone is to favour energy storage over energy usage, therefore leading to weight gain and obesity. High levels of fasting insulin have shown to inhibit lipolysis and promote lipogenesis contributing to obesity. Hyperinsulinemia enhances the risk of cardiovascular disease by increasing vascular tone, enhancing the reabsorption of sodium by the kidneys, adhesion of macrophages to the vessel wall and development of arterial lesions with increased lipoprotein lipase activity and cardiovascular disease.
Obesity: Is directly linked to individuals diagnosed and living with type 2 diabetes. A person's body mass directly correlates to the risk of developing type 2 diabetes due to the physiological characteristics of obesity. These characteristics include the increase in adipose tissue which causes alterations in pancreatic beta cell function and multi-organ insulin resistance, discussed above.
Beta cells are located in the pancreas and their primary role is to secrete insulin when a high blood sugar level is detected (postprandial). Beta cell dysfunction is the critical determinant for type 2 diabetes and is an essential component of insulin resistance. Beta cell dysfunction is characterised by impaired insulin secretion as opposed to insulin insensitivity associated with insulin resistance. There are both vital pathways in maintaining healthy blood glucose levels in the body. Beta cell dysfunction leads to the progression of diabetes due to the chronic state of hyperglycemia (prolonged elevated levels of blood sugar). However, many studies have identified the positive outcome of weight loss on beta cell functioning which improves an individual’s fasting blood glucose levels reducing type 2 diabetes risk.
Carbohydrate timing: There are three macronutrients essential for survival: fats, proteins and carbohydrates. Out of these, carbohydrates are the only macronutrients that affect blood sugar levels. When a carbohydrate food is consumed, whether it is bread, sugar or a sweet potato, the body digests these carbohydrates down into glucose which is then released into the bloodstream. Knowing when to eat carbohydrates throughout the day has a huge impact on an individual’s blood sugar levels. Therefore it is essential to discuss this with a dietitian to ensure carbohydrates are being utilised correctly to either reduce the risk of developing type 2 diabetes or better manage blood sugar levels in type 2 diabetes. The timing of these foods around exercise is also important and is where an exercise physiologist can provide further support.
Carbohydrate types (Glycemic Index): As previously stated, carbohydrate foods are not made equally. It is quite clear that a chocolate bar and a cob of corn have very different nutritional profiles but are both carbohydrate foods. The main difference between these two foods is their Glycemic Index (GI). Glycemic index is the term used for how quickly a carbohydrate food is broken down to sugar and released into the blood. High GI foods are broken down very quickly and tend to spike blood sugar levels. Alternatively, low GI foods are broken down much more slowly and provide a more sustainable release of sugar into the bloodstream. Understanding different types of carbohydrate foods and their GI is an essential component of managing type 2 diabetes.
Your dietitian must understand the above information to prescribe appropriate dietary choices. In addition to understanding the physiology of diabetes and the impact diet has on this, here's how our dietitians directly assist individuals with type 2 diabetes:
Assessing individual needs: The first step is to assess the specific needs and limitations of the person with type 2 diabetes. This assessment includes considering current dietary intake, medical history, any complications related to diabetes, and individual goals.
Creating tailored meal plans: Based on the assessment, we then develop a personalised meal plan. This plan will be tailored to suit each individual’s dietary needs in relation to specific weight and health goals. Some examples of tailored meal plans specific to diabetes management may include a low carbohydrate diet, low GI carbohydrate diet, and high protein diet.
Educating on diabetes management: Providing education is essential for a person with type 2 diabetes to be successful at managing their diabetes for their entire lifespan. Initially, our dietitians will provide education about the relationship between food choices and diabetes. Education becomes more specific as specific goals are set at each visit. For example, one bout of education may involve low GI food choices, the next may focus on carbohydrate portions at meals and snacks to suit activity levels.
Promoting lifestyle changes: The goal of a dietitian is to provide education, support and interventions to encourage a person with type 2 diabetes to make lifestyle changes. By achieving lifestyle changes gradually, the person can make changes that will be sustainable and achievable.
Providing motivation and support: A tailored plan with both short-term and long-term goals provides support and motivation when a person is living with type 2 diabetes. The ongoing connection between the dietitian and the client helps to encourage accountability in the early stages of lifestyle change and is important for motivation.
Reducing the risk of complications: Many clients living with type 2 diabetes can have other comorbidities and these are often related to years or decades of unmanaged blood sugar levels. Complications of diabetes include renal failure, heart failure, loss of sight and peripheral neuropathy. Early intervention is imperative to reducing the risks associated with type 2 diabetes. It is highly encouraged to seek dietetic support as early as possible.
Collaborating with healthcare teams: We often work as part of a healthcare team to ensure a holistic approach to diabetes management. We may communicate with GP’s, diabetes educators, and other specialists to provide the best possible care for the individual.
Overall, our dietitians play a vital role in helping individuals with type 2 diabetes improve their nutritional understanding and food choices to better their quality of life through understanding type 2 diabetes. Through personalised guidance and ongoing support, our dietitians contribute to improved dietary intake, better blood sugar control and better overall health for individuals with diabetes.