More than 37 million Americans (about 10%) have diabetes, and approximately 90-95% of these individuals have type 2 diabetes. In addition, 38% of US adults have prediabetes, and increasing numbers of children, teens, and young adults (1) are also developing type 2 diabetes.
Type 2 diabetes is a disease that occurs when an individual's blood glucose, or blood sugar, is chronically high. It is caused when the body becomes resistant to insulin, and the cells do not respond appropriately. While genetics plays a role in developing insulin resistance, lifestyle choices, including diet and exercise, are predominant factors contributing to type 2 diabetes.
A Functional Medicine approach to type 2 diabetes focuses on diet and lifestyle changes and is a leading-edge and effective strategy for managing and preventing type 2 diabetes.
What are The Signs and Symptoms of T2D?
Typical symptoms of diabetes (2) may be very vague and include fatigue, sugar cravings, the inability to lose weight, and constant hunger. However, some people with type 2 diabetes have symptoms so mild that they go unnoticed. Others may have no signs or very vague symptoms like fatigue. This is sometimes called silent diabetes, and while the person may feel fine, significant damage to the nerves, blood vessels, and organs begins to occur.
Common Symptoms of Type 2 Diabetes:
- Frequent thirst and urination.
- Poor wound healing.
- Eye-related symptoms such as blurry vision, cataracts, glaucoma, and retinopathy.
- Extreme fatigue.
- Blurry vision.
- Cuts/bruises that are slow to heal.
- Tingling, pain, or numbness in the hands/feet.
- Poor circulation that can lead to amputation of fingers, toes, and limbs.
Insulin resistance and prediabetes are often present long before diabetes is diagnosed. It is not unusual for people to feel the need to eat every few hours to avoid crashing. This inability to go more extended periods without eating is a symptom of poor blood sugar control and should not be dismissed. Diabetes requires a medical diagnosis, but every individual can assess early symptoms of diabetes and hypoglycemia, including:
- Shaky or lightheadedness
- Sweet cravings
- Irritability if meals are delayed
- Inability to sleep or waking after a few hours
- Mood swings
- Brain fog
- Fatigue or energy fluctuations
What Is The Difference Between Type 1 Diabetes and Type 2 Diabetes?
There are actually three types of Diabetes:
Type 1 Diabetes
Type 1 diabetes is also called juvenile diabetes or insulin-dependent diabetes and is an autoimmune disease.
In Type 1 diabetes, the body's immune system attacks the cells that produce insulin in the pancreas. Insulin is needed to manage blood sugar levels and provide energy. The risk factors for type 1 diabetes are family history and genetics, and this condition usually occurs in children 4-14 years old but can be diagnosed at any age.
Type 1.5 Diabetes
Another form of diabetes that is becoming more prevalent as the rates of autoimmune disease increase in our country is Latent Autoimmune Diabetes in adults (LADA), or type 1.5 diabetes.
Type 1.5 diabetes has a slower onset than Type 1 diabetes and is different from type 2 diabetes as it is caused by autoimmune vs. other risk factors.
Type 2 Diabetes
The Diabetes Risk Test is an assessment tool to learn about your risk for type 2 diabetes. The rate of diabetes is expected to double or triple by 2050 (3); these projections show epidemic levels of this condition in the near future.
Type 2 Diabetes Risk Factors
A person is at an increased risk for type 2 diabetes if they:
- Over the age of 45
- Has prediabetes
- Had gestational diabetes while pregnant
- Has a family history of diabetes
- Is overweight or obese
- Is Black or African American, Hispanic/Latino, American Indian, Asian American or Pacific Islander
- Is not physically active
- Has other conditions such as high blood pressure, heart disease, stroke, polycystic ovary syndrome (PCOS), or depression
- Has low HDL cholesterol and high triglycerides
- Has acanthosis nigricans
What is Insulin Resistance?
Type 2 diabetes usually begins with insulin resistance, a condition in which muscle, liver, and fat cells do not use insulin well. As a result, the body needs more insulin to help glucose enter cells. At first, the pancreas makes more insulin to keep up with the added demand. Over time, the pancreas can't make enough insulin, and blood glucose levels rise. This leads to prediabetes and, ultimately, type 2 diabetes if not corrected. People with insulin resistance or prediabetic have a 50% chance of developing type 2 diabetes within 5 to 10 years.
Blood sugar regulation is complex. However, a simplified explanation of the process in an individual with good blood glucose control can be summarized as follows:
- Blood glucose levels rise due to eating food that includes some form of carbohydrate.
- Glucose enters the bloodstream, which signals the pancreas to release insulin
- This appropriate insulin response helps the blood sugar (glucose) enter the cells.
- The glucose in the cells can be used for energy or stored in the liver for later use.
- Low insulin levels throughout the day signal the liver to release stored glucose if a person has not eaten in a while.
- Blood sugar remains normal throughout the day without going too high or too low.
Conversely, a person with impaired blood sugar handling (hyperglycemia, high blood sugar, prediabetes, or type 2 diabetes) will process glucose in the following way:
- High glucose levels are in the bloodstream, either from chronically elevated blood sugar or regularly consuming high levels of glucose in the form of carbohydrates.
- The pancreas produces more insulin to help the blood sugar get into the cells.
- Over time, the cells stop responding to insulin and become insulin resistant.
- The pancreas keeps making more insulin to try to make cells respond.
- At some point, the pancreas cannot produce enough insulin, and blood sugar keeps rising.
Lab tests and other preventative tools can be used to identify if a person has insulin resistance, prediabetes, and type 2 diabetes. All individuals can benefit from regularly assessing blood sugar and insulin markers to learn how well their body handles glucose.
How to Test for Type 2 Diabetes
Testing is important. Here are helpful labs for this condition:
According to the National Institute for Diabetes and Digestive and Kidney Diseases (NIDDK), people are not usually tested for insulin resistance.
The best testing method for insulin resistance is complicated and used mainly in research. Instead, blood tests that measure the level of glucose in the bloodstream are used. Less often, doctors use the oral glucose tolerance test (OGTT), which is one of the most sensitive measures of early glucose dysregulation but requires a significant investment in patient time.
The two most common tests for blood sugar are a standard fasting blood glucose test and hemoglobin A1c (also called HbA1c or A1c) blood test.
Fasting Glucose (Fasting Plasma Glucose, FPG) is routinely measured in a basic panel and measures the glucose when the blood is drawn. This does not allow for variability over time and, therefore, can be most helpful when used in conjunction with other lab tests. If elevated, always follow up with further testing.
Normal: A fasting blood sugar level of less than 100 mg/dL (5.6 mmol/L).
Prediabetes: A fasting blood sugar level from 100 to 125 mg/dL (5.6 to 6.9 mmol/L).
Diabetes: 126 mg/dL (7 mmol/L) or higher on two separate tests.
Hemoglobin A1c (HbA1c or A1c) provides a complete picture of the individual's blood sugar regulation as it measures the average amount of glucose in the bloodstream over three months. HbA1c is measured in percentages:
Prediabetes: HbA1c level between 5.7% and 6.4%
Diabetes: HbA1c level at 6.5% or above
Two commonly ordered follow-up tests are fasting insulin and LDH.
Fasting Insulin is used to assess insulin production; if elevated, this could indicate insulin resistance.
Normal fasting insulin reference ranges are quite broad, 2.6-24.9 mcIU/ml. Still, research has correlated fasting insulin levels over 7 as associated with a significant increase in future risk of metabolic syndrome and type II diabetes.
LDH (lactate dehydrogenase) This enzyme, when decreased, can indicate that glucose is not getting into the cell and can indicate insulin resistance.
Other Useful Labs
Markers for metabolic syndrome, also called Syndrome X, are important in assessing overall metabolic health and glucose regulation. Metabolic syndrome is a collection of symptoms seen in prediabetes and diabetes that increase the likelihood of cardiovascular disease involvement.
- Elevated triglycerides > 110
- Elevated cholesterol > 220
- Decreased HDL <55
- Elevated blood pressure higher than 120/80
- Obesity with BMI >30
This panel includes cholesterol, triglycerides, and HDL and can be used to assess cardiovascular risk.
Liver Enzymes & CMP
Increased levels of liver enzymes (aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyltranspeptidase (GGT)) included in a liver panel or a comprehensive metabolic panel are indicators of hepatocellular injury. Increased activity of these markers is associated with insulin resistance, metabolic syndrome, and type 2 diabetes.
Comprehensive Stool Test
A healthy gut microbiome is essential for blood sugar control and weight management. A Comprehensive Stool Test detects microbial imbalances, microbes contributing to illness, and indicators of digestion, absorption, inflammation, and immune function. It is also helpful for assessing digestive function before making significant dietary changes. If a person is not digesting fats and proteins, it will be challenging to adapt to a lower carbohydrate diet. In addition, the GI-MAP includes a few markers related specifically to blood sugar:
- Akkermansia muciniphila- Low levels are associated with obesity and metabolic dysfunction.
- Bacteroidetes and Firmicutes- An abnormal result in either phylum suggests imbalanced normal microbes in the GI tract. High Firmicutes and low Bacteroidetes (resulting in a high F/B ratio) indicate a microbial imbalance, which may be related to increased caloric extraction from food, fat deposition and lipogenesis, impaired insulin sensitivity, and increased inflammation.
Treatment for Type 2 Diabetes
Although type 2 diabetes is very common, it should be noted that complications from this disease are very serious. Diabetes is the 7th leading cause of death. It has a higher associated risk of blindness, Alzheimer's, kidney failure, heart disease, stroke, and peripheral neuropathy (that can lead to amputation of toes, feet, or legs). Catching insulin resistance early is critical. Once metabolic syndrome exists, it becomes even more challenging to reverse the trend, and aggressive supplementation, lifestyle, stress, and dietary strategies are needed.
People with hypoglycemia and diabetes are encouraged to introduce changes slowly. The primary goals are to stabilize blood glucose.
Small changes in the types of foods should be considered at this time:
- Avoid processed sugar
- Choose nutrient-dense carbohydrates
- Include anti-inflammatory foods, avoid fried foods and hydrogenated fats
- Consider a whole-foods diet that suits the individual's lifestyle the best (ex. paleo, Mediterranean, anti-inflammatory, diabetic diet)
This first-line approach can help prepare a person to successfully control blood sugar and prepare the body for any next steps that can further reverse insulin resistance, including intermittent Fasting.
Intermittent Fasting (IF) is an eating pattern where an individual cycles between eating and fasting periods. Therapeutic Fasting has been shown to reverse insulin resistance and improve metabolic health. Fasting and time-restricted eating can also promote autophagy and can potentially increase longevity.
Various types of intermittent fasting can be used:
- Time-Restricted Feeding is the most common IF method. Food consumption is allowed during a specified window of time each day, for example, the 16/8 method (8-hour eating window) or one meal a day (OMAD).
- Periodic Fasting is when individuals fast or eat low calories (ex 500 calories) or fast for 1 or 2 days a week, and then eat normally the other days (also referred to as 5:2 or 6:1 fasting).
- Alternate Day Fasting, or fasting every other day.
- Eat Stop Eat is a 24-hour fast once or twice per week.
- Fasting Mimicking Diet is an intermittent fasting plan that restricts calories and mimics fasting for a set period (ex., 5 days at 500 calories), but during this time, a person does not stop eating entirely.
*Note: If you are diabetic or prediabetic, it is vital to work with your healthcare provider before starting a fasting type diet.
What Food to Avoid with Type 2 Diabetes
This "foods to avoid list" combines highly processed carbohydrates and highly inflammatory foods that should be limited. Instead, focusing on a diabetic diet with healthy carbohydrates, fiber-rich foods, fish, and "good" fats can be beneficial for improving metabolic health and insulin resistance over time.
Foods to Avoid
- Fructose and sugar-sweetened beverages (juice, soda, punch, sweetened tea, sports drinks, coffee drinks)
- Sweets (candy, cookies, baked goods, ice cream, desserts)
- Sweeteners (table sugar, brown sugar, honey, maple syrup, molasses)
- Bread, pasta, cereal
- Milk and processed cheese
- Industrial Seed oils, margarine, and trans fats (vegetable shortening, fried foods, dairy-free coffee creamers, partially hydrogenated oil)
- Packaged and refined foods (chips, microwave popcorn, processed meat, convenience meals)
- Alcohol, especially beer or sweetened alcoholic drinks
- High Glycemic Foods
High Glycemic Foods
The glycemic index of foods has been studied in reference to glucose control and can help determine the best food choices for an individual with diabetes. The glycemic index is a value assigned to foods based on how quickly and how high those foods cause increases in blood glucose levels. Foods low on the glycemic index (GI) scale tend to release glucose slowly and steadily, while foods with a high glycemic index release glucose rapidly. Examples of foods with a high glycemic index (GI of 70 or higher) include white bread, rice cakes, most crackers, bagels, cakes, doughnuts, croissants, and packaged breakfast cereals.
- B vitamins are essential in blood sugar handling, especially B1 (thiamine), B6 (pyridoxine), folate, and B12. *People who take metformin for type 2 diabetes have lower levels of vitamin B12. If you're on metformin, talk to your health care provider about periodically being tested for a B12 deficiency.
- Zinc can improve insulin sensitivity and also plays a role in insulin metabolism. At this time, there are no guidelines for Zinc measurement or supplementation in diabetes; however, ensuring Zn as a part of regular dietary requirements through healthy food or oral supplementation can positively affect diabetes health.
- Magnesium is a cofactor of many enzymes involved in glucose metabolism and has an essential role in insulin action.
- Chromium A chromium deficiency may lead to high blood sugar levels. It may be worth trying if you're deficient in chromium, but that's very rare. Steer clear if you've been diagnosed with kidney disease. Chromium supplements might further damage the kidneys and worsen the disease.
- Fiber Increasing soluble fiber, in the form of a supplement or through food, leads to lower HbA1c levels in type 2 diabetes.
- Exercise: Research indicates exercise can reduce the risk of type 2 diabetes by almost 50 percent. High-intensity interval training (HIIT) can be beneficial for lowering blood sugar and associated cardiovascular risks.
- Reducing the amount of time spent sedentary during the day is also essential. If an individual's job is sedentary, a standing desk or treadmill desk can be used. If that is not an option, standing up more and taking walking breaks are beneficial.
Regular blood sugar testing can help people learn how foods and physical activity affect glucose levels. A glucometer, or blood glucose meter, can assess blood sugar handling throughout the day. This low-cost device can be purchased at most drug stores. The individual pricks a finger with a needle-tipped tool called a lancet and collects a small blood sample on the test strip. Blood glucose can be taken before eating and then 1, 2, 3, or 4 hours after eating a meal.
Continuous glucose monitors (CGM) are small wearable devices that measure the glucose level in the interstitial fluid. The development of CGM devices that can frequently and easily monitor blood sugar levels without finger sticks greatly benefits those measuring several times throughout the day.
Depending on the individual's insurance and diagnosis, continuous glucose monitors may be covered by insurance. It can be cost-prohibitive for many people without insurance, but as more companies meet the demand for this product, the cost is expected to go down over time.
Research indicates a relationship between sleep duration and type 2 diabetes. Individuals that slept between 7-8 hours per night had the lowest risk of diabetes, while less than 7 hours of sleep is associated with a higher risk. The circadian system regulates glucose metabolism, and sleep disruptions impact glucose control. Going to bed and waking up at the same time every day is ideal for people managing blood glucose levels.
Under conditions of stress, the body produces higher levels of the hormone cortisol. Cortisol plays several critical roles, including increasing blood sugar for quick bursts of energy. This "fight or flight" response is helpful in many situations, but cortisol will increase blood sugar to unhealthy levels if the stressor becomes chronic. Even if a person is otherwise healthy- eats a healthy diet, exercises, and is a healthy weight- chronic stress can increase cortisol levels and lead to chronically elevated glucose levels and increase the risk of type 2 diabetes.
Everyone can improve metabolic function and reduce the risk for type 2 diabetes no matter where they are currently. Slowly making shifts in diet and lifestyle can profoundly change physiology. Some people may need to correct their blood sugar, while others can work on optimizing glucose control. Lab testing can be beneficial in assessing current glucose function and metabolic health. This can be especially important for prediabetes or silent diabetes without any symptoms. Fortunately, individualized dietary and lifestyle changes can be used to address chronically elevated blood sugar and ideally reverse insulin resistance.
Articles That May Interest You
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