Diabetes mellitus is a chronic disease that is becoming more prevalent worldwide. Diabetes causes high blood sugar, which is harmful to health.
As of 2015, 30.3 million people in the United States, or about 9.4 percent of the population, had diabetes. Unfortunately, more than 1 in 4 people with diabetes don’t know they have it. Having undiagnosed diabetes increases the risk of diabetes-related complications such as kidney disease, heart disease, amputations, and more.
Many people also have prediabetes, a condition where blood sugars are slightly elevated but not high enough to be considered diabetes. Having prediabetes is a significant risk factor for eventually developing type 2 diabetes.
The U.S. Centers for Disease Control (CDC) estimates that up to 30% of people with prediabetes will develop type 2 diabetes within five years of their prediabetes diagnosis.
The majority of people with diabetes have type 2, which typically affects older adults and can be related to multiple known risk factors, including race, weight, and some lifestyle factors. Type 1 diabetes is more rare as it’s an autoimmune disorder. Type 1 usually occurs before age 18, so it’s also referred to as juvenile diabetes. Type 1 diabetes affects about 2-5% of the world’s population or about 1 in 300 American adults before the age of 18.
One of the reasons diabetes is so prevalent is because it often doesn’t have symptoms until it’s progressed far enough to be diagnosed.
Many people with prediabetes have no idea that they are at increased risk of diabetes, only to find out a few years later when they experience enough symptoms to seek medical attention.
Knowing some of the signs of high blood sugar can help people identify when they might need to seek medical attention, whether they have diabetes or not.
Get Your FREE Diabetes Diet Plan
- 15 foods to naturally lower blood sugar levels
- 3 day sample meal plan
- Designed exclusively by our nutritionist
What does high blood sugar feel like?
Having acute high blood sugar (also called hyperglycemia) generally doesn’t result in any overt symptoms like heartburn or catching a cold. However, if high blood sugar becomes chronic, meaning it lasts for a long time, some symptoms can arise. These symptoms occur because having blood sugar that is either too high or too low isn’t normal and causes an imbalance in the body.
Cells require sugar (glucose) for energy, and glucose is the preferred energy source over other sources the body can use, such as fatty acids. Insulin is a hormone produced by the pancreas and is responsible for helping to lower blood sugar levels.
Cells have insulin receptors, which insulin attaches to in order to let the sugar in. Another way to think of it is that cells have doors, the insulin receptors are the doorknobs, and insulin is the key to open the doorknob to allow sugar to feed the cells. Without enough insulin, the sugar stays in the bloodstream and accumulates, unable to enter the cell.
Some symptoms of high blood sugar include:
- Increased thirst and/or hunger
- Frequent urination
- Nausea and vomiting
- Shortness of breath
- Stomach pain
- Fruity-smelling breath
- A very dry mouth
- A rapid heartbeat
- Unintentional weight loss
Without enough insulin to provide glucose to feed the cells, the body starts burning fat and muscle for energy instead. This leads to unintentional weight loss and can also result in increased hunger to try to provide enough energy for the body to function.
In the case of type 1 diabetes, a serious condition called diabetic ketoacidosis (DKA) can occur if blood sugar level remains very high. This can occur from missing insulin doses or even being ill. DKA occurs when insulin levels are very low, which causes the body to start producing ketones to use as fuel instead of glucose. A sign of ketone bodies being present is fruity-smelling breath. DKA can be fatal, so prompt medical attention is required.
Symptoms of DKA are similar to those of a high blood glucose level and include:
- Excessive thirst
- Frequent urination
- Abdominal pain
- Nausea and vomiting
In type 2 diabetes, very high blood sugar can cause hyperglycemic hyperosmolar syndrome (HHS). HHS doesn’t cause ketones to build up, but it does present as:
- Very high blood sugar
- Decreased alertness
On the other hand, low blood sugar (hypoglycemia) has distinct symptoms as well and occurs when blood sugars are less than 70 mg/dL.
Symptoms of low blood sugar include:
- Shakiness or nervousness
- Dizziness or lightheadedness
- Difficulty speaking
People who have had diabetes for a long time can develop hypoglycemia unawareness, meaning they don’t feel low blood sugar symptoms. This can lead to severe hypoglycemia, which can cause the person to lose consciousness and even go into a diabetic coma. It tends to occur more often in people with type 1 diabetes.
When should I call my doctor about having high blood sugar?
If you don’t have a diagnosis of diabetes and think you might be having symptoms of high blood sugar, it would be a good idea to have a blood sugar screening done to determine if you have prediabetes or diabetes.
This is especially important if you also have one or more of the risk factors for developing type 2 diabetes (the most common type), such as:
- Weight: People who are considered overweight or obese according to their body mass index (BMI).
- Age: people 45 and older are at increased risk.
- Family history of diabetes
- Race/ethnicity: diabetes tends to affect certain races more than others. At-risk races include African American, Alaska Native, Native American, Asian American, Hispanic/Latino, Native Hawaiian, or Pacific Islander.
- High blood pressure: if your blood pressure is higher than 120/80, you may be at increased risk.
- Altered lipid levels: low levels of HDL “good” cholesterol and high levels of LDL “bad” cholesterol are risk factors, as well as high triglycerides (blood fat).
- Pregnancy history: women with a history of gestational diabetes (GDM) or who gave birth to a baby 9 pounds or heavier are at increased risk.
- Physical activity: People who aren’t regularly active or have a sedentary lifestyle are at increased risk.
- Smoking status: Smokers are 30-40% more likely to develop type 2 diabetes than nonsmokers.
- Health history: those with a history of heart attack or stroke have a higher likelihood of developing type 2 diabetes.
- PCOS: Polycystic Ovarian Syndrome in women is a risk factor, as it usually is associated with insulin resistance.
- Acanthosis nigricans: dark, velvety patches of skin are a sign of insulin resistance and are a risk factor for developing diabetes. These patches of skin usually occur around the neck or armpits.
For those with diabetes, medical attention should be sought will depend on the person and their individual blood sugar targets and normal blood sugar trends.
However, in general, it’s advisable to contact your healthcare provider if blood sugar levels are consistently above 200 mg/dL. Medical attention should also be sought for the following symptoms, especially when coupled with high blood sugar:
- Trouble breathing
- High levels of ketones in your urine
- Extreme thirst or a very dry mouth
- Having to urinate too often
- Dry or flushed skin
- Breath that smells like fruit
People with type 1 diabetes may want to keep ketone strips on hand to test for ketones and diabetic ketoacidosis. Having ketones present in the urine is a sign of very high blood sugar and low insulin levels and needs to be treated to prevent complications.
What can happen if my blood sugar stays high for too long?
Having high blood sugar every once in a while isn’t as big of a concern as having chronically high blood sugar levels.
High blood sugar damages the arteries and vessels supplying blood to all of the body’s organs. This means that any part of the body can become damaged from chronic hyperglycemia since all aspects of the body rely on blood supply.
Some of the complications from chronic high blood sugar include:
- Heart (cardiovascular) disease: people with diabetes are two to four times more likely to die from cardiovascular disease than those without diabetes. People with diabetes are also more likely to have high blood pressure, which is another risk factor for heart disease. A heart attack is one potential complication of heart disease.Cholesterol goals are more strict for people with diabetes because of this increased risk. Elevated levels of LDL (bad) cholesterol and low levels of HDL (good) cholesterol are some risk factors for developing heart disease.
- Stroke: Diabetes increases the risk of stroke, as well as increases mortality when a stroke occurs. It’s estimated that 65% of diabetes-related deaths are attributable to stroke, cardiovascular disease, or both.
- Kidney disease and failure: High blood sugar damages the kidneys and can lead to kidney disease. About one in four people with diabetes have kidney disease. It’s recommended that people with diabetes have kidney function tests such as estimated glomerular filtration rate (eGFR) and urine microalbumin yearly to detect kidney damage.
- Poor wound healing: High blood sugar inhibits proper wound healing. Ulcerations and other wounds that don’t heal properly can even lead to the need for an amputation. Diabetes is thought to be the leading cause of leg amputations worldwide.
- Neuropathy: Damage to the nerves, which can cause painful symptoms like numb and tingling legs and feet, as well as delayed stomach emptying from damage to the nerves of the stomach.
- Retinopathy and blindness: Damage to the nerves in the eyes is called retinopathy, which can lead to blindness if not treated.
- Teeth and gum infections: High blood sugar levels can cause inflammation and delay healing. High sugar levels in the saliva can cause increased cavities in teeth and cause bacteria to grow, leading to gingivitis (gum disease).
According to the American Diabetes Association (ADA), these are the goals for blood sugar in those with diabetes, though individual blood sugar goals may vary:
How to efficiently treat high blood sugar
There are many different treatment methods for high blood sugar. Treatment depends on the type of diabetes, the severity of high blood sugar, duration of having diabetes, and many other factors. This means that one person’s diabetes treatment plan will likely look much different than someone else’s.
Healthy diet: Carbohydrates in foods like fruits, certain vegetables, legumes, grains, and milk turn into sugar when digested, which means they have a big impact on blood sugar levels. A healthy diet for diabetes should emphasize fiber-rich carbohydrates and eat carbohydrates consistently throughout the day to promote steady blood sugars.
Blood sugar levels can improve by eating a healthy diet such as a Mediterranean diet or following the Plate Method, combined with other healthy lifestyle habits.
A Mediterranean diet focuses on nutrient-dense foods, avoids refined sugars and red meat, and has improved health outcomes, including improved blood sugar levels and improved cardiovascular outcomes. A Mediterranean diet includes foods such as:
- Vegetables: Tomatoes, broccoli, kale, spinach, onions, cauliflower, carrots, Brussels sprouts, cucumbers, etc.
- Fruits: Apples, bananas, oranges, pears, strawberries, grapes, dates, figs, melons, peaches, etc.
- Nuts and seeds: Almonds, walnuts, macadamia nuts, hazelnuts, cashews, sunflower seeds, pumpkin seeds, etc.
- Legumes: Beans, peas, lentils, pulses, peanuts, chickpeas, etc.
- Tubers: Potatoes, sweet potatoes, turnips, yams, etc.
- Whole grains: Whole oats, brown rice, rye, barley, corn, buckwheat, whole wheat, whole-grain bread, and pasta.
- Fish and seafood: Salmon, sardines, trout, tuna, mackerel, shrimp, oysters, clams, crab, mussels, etc.
- Poultry: Chicken, duck, turkey, etc.
- Eggs: Chicken, quail, and duck eggs.
- Dairy: Cheese, yogurt, Greek yogurt, etc.
- Herbs and spices: Garlic, basil, mint, rosemary, sage, nutmeg, cinnamon, pepper, etc.
- Healthy Fats: Extra virgin olive oil, olives, avocados, and avocado oil.
Physical activity: 150 minutes per week of moderate to vigorous activity is recommended for people with and without diabetes. Strength or resistance training a few days per week is also recommended. It can help reduce insulin resistance and improve blood sugars by increasing the amount of glucose absorbed by the muscles to use as fuel.
Medications: For some people, lifestyle changes alone might not be enough to improve blood sugar levels. Needing medication isn’t a sign of failure but is a sign that the pancreas can’t produce enough insulin on its own to help lower blood sugars. Some of the more popular medications used to treat diabetes include:
- Metformin: Helps to reduce the amount of sugar released by the liver and improves insulin sensitivity.
- Sulfonylureas: Stimulate the pancreas to secrete more insulin.
- GLP1 receptor agonists: Promote insulin production, decrease glucose release from the liver, and slows stomach emptying to increase satiety.
- DPP-4 inhibitors: Promote insulin production, decrease glucagon (a hormone that increases blood sugar) production and delays gastric emptying.
- Insulin is available in different types: long-acting, short-acting, rapid-acting, intermediate-acting, and mixed. They differ in how quickly they take to work, how long until they are working the most to lower blood sugar and how long they last to provide blood sugar control. Insulin can be delivered through an insulin pump for those with type 1 diabetes.
Having high blood sugar can cause health problems when left untreated. When high blood sugar is short-term, it generally doesn’t have symptoms. However, chronic high blood sugar can result in symptoms such as increased hunger, thirst, urination, and fatigue, among other symptoms.
Normal blood sugar levels in people without diabetes generally fall between 70-140 mg/dL. Blood sugar below 70 mg/dL is considered low, and blood sugar above 140 mg/dL after eating is considered high for someone without diabetes. Normal blood sugar for a diabetic varies depending on individual treatment goals but usually fall around the same range as people without diabetes (70-140 mg/dL).
Very high blood sugar can be life-threatening. In people with type 1 diabetes, very high blood sugar can lead to a condition called diabetic ketoacidosis, or DKA. In people with type 2 diabetes, very high blood sugar can cause hyperglycemic hyperosmolar syndrome or HHS. Both of these conditions require prompt medical attention.
High blood sugar damages the arteries and blood vessels supplying blood to the body’s organs. Long-term complications from high blood sugar can include heart disease, stroke, nerve damage, poorly-healing wounds, and eye damage. A good diabetes care plan can help prevent complications from promoting healthy blood sugar levels.
High blood sugar can be prevented by a combination of eating a healthy diet, being physically active, and taking medications as prescribed by a healthcare provider.