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Symptoms and Signs of Diabetes (Type 1 and Type 2)

Doctor's Notes on Diabetes (Mellitus, Type 1 and Type 2)

Diabetes (type 1 and type 2) is a disease where the body’s ability to produce or respond to the hormone insulin is impaired. Common signs and symptoms type 1 and type 2 diabetes include

Type 1 diabetes is when the body either stops insulin production or produces too little insulin to regulate blood glucose levels.

Type 2 diabetes is when the body is partially or completely unable to respond to insulin.

  • It is usually diagnosed in adults (45 years and older).
  • Symptoms type 2 often develop very gradually.
  • Type 2 diabetes, untreated, can lead to nerve damage, blindness, kidney failure, hyperglycemic hyperosmolar nonketotic syndrome (extremely high levels of blood glucose, causing coma or death) and heart disease.

Diabetes (type 1 and type 2) Causes

  • Type 1 diabetes is an autoimmune disease where the body’s immune system attacks the pancreatic cells that make insulin.
  • Type 2 diabetes causes are less clear; however, such factors as genetics, obesity, high fat levels in the blood and the diet, high blood pressure, sedentary lifestyle, ethnicity, birthing a baby weighing more than 9 lbs. and aging may play a role in type 2 development.

Medical Author:
Medically Reviewed on 5/3/2019

Diabetes (Mellitus, Type 1 and Type 2) Symptoms

Symptoms of type 1 diabetes are often dramatic and come on very suddenly.

  • Type 1 diabetes is usually recognized in childhood or early adolescence, often in association with an injury or illness (such as a virus or urinary tract infection).
  • The extra stress can cause diabetic ketoacidosis (DKA).
    • Symptoms of ketoacidosis include nausea and vomiting. Dehydration and often-serious disturbances in blood levels of potassium and other factors follow.
    • Without treatment, ketoacidosis can lead to coma and death.

Symptoms of type 2 diabetes are often subtle and may be attributed to aging or obesity.

  • A person may have type 2 diabetes for many years without knowing it.
  • People with type 2 diabetes can develop the hyperglycemic hyperosmolar nonketotic syndrome.
  • Type 2 diabetes can be precipitated by steroids and stress.
  • If not properly treated, type 2 diabetes can lead to complications such as blindness, kidney failure, heart disease, and nerve damage.

Common symptoms of both type 1 and type 2 diabetes include:

  • Fatigue, or feeling constantly tired: In diabetes, the body is inefficient and sometimes unable to use glucose for fuel. The body switches over to metabolizing fat, partially or completely, as a fuel source. This process requires the body to use more energy. The end result is feeling fatigued or constantly tired.
  • Unexplained weight loss: People with diabetes are unable to process many of the calories in the foods they eat. Thus, they may lose weight even though they eat an apparently appropriate or even an excessive amount of food. Losing sugar and water in the urine and the accompanying dehydration also contributes to weight loss.
  • Excessive thirst (polydipsia): A person with diabetes develops high blood sugar levels, which overwhelms the kidney's ability to reabsorb the sugar as the blood is filtered to make urine. Excessive urine is made as the kidney spills the excess sugar. The body tries to counteract this by sending a signal to the brain to dilute the blood, which translates into thirst. The body encourages more water consumption to dilute the high blood sugar back to normal levels and to compensate for the water lost by excessive urination.
  • Excessive urination (polyuria): Another way the body tries to rid the body of the extra sugar in the blood is to excrete it in the urine. This can also lead to dehydration because a large amount of water is necessary to excrete the sugar.
  • Excessive eating (polyphagia): If the body is able, it will secrete more insulin in order to try to manage the excessive blood sugar levels. With type 2 diabetes, the body resists the action of insulin. One function of insulin is to stimulate hunger. Therefore, higher insulin levels lead to increased hunger. Despite eating more, the diabetic person may gain very little weight and may even lose weight.
  • Poor wound healing: High blood sugar levels prevent white blood cells, which are important in defending the body against bacteria and also in cleaning up dead tissue and cells, from functioning normally. When these cells do not function properly, wounds take much longer to heal and become infected more frequently. Long-standing diabetes also is associated with thickening of blood vessels, which prevents good circulation, including the delivery of enough oxygen and other nutrients to body tissues.
  • Infections: Certain infections -- such as frequent yeast infections of the genitals, dental infections, skin infections, and frequent urinary tract infections -- may result from suppression of the immune system by diabetes and by the presence of glucose in the tissues, which allows bacteria to grow. These infections can also be an indicator of poor blood sugar control in a person known to have diabetes.
  • Altered mental status: Agitation, unexplained irritability, inattention, extreme lethargy, or confusion can all be signs of very high blood sugar, ketoacidosis, hyperosmolar hyperglycemia nonketotic syndrome, or hypoglycemia (low sugar). Thus, any of these in a diabetic patient merit the immediate assessment of blood glucose. Call your health-care professional or 911 for immediate attention by a medical professional.
  • Blurry vision: Blurry vision is not specific for diabetes but is frequently present with high blood sugar levels.

Diabetes (Mellitus, Type 1 and Type 2) Causes

Type 1 diabetes: Type 1 diabetes is an autoimmune disease. The body's immune system specifically attacks the cells in the pancreas that produce insulin.

  • A predisposition to develop type 1 diabetes may run in families, but genetic causes (a positive family history) are much more common for type 2 diabetes.
  • Environmental factors, including common and unavoidable viral infections, may also contribute to type 1 diabetes.
  • Type 1 diabetes is most common among people of non-Hispanic, Northern European descent (especially Finland and Sardinia), followed by African Americans, and Hispanic Americans. It is relatively rare among people of Asian descent.
  • Type 1 diabetes is slightly more common in men than in women.

Type 2 diabetes: Type 2 diabetes has strong genetic links, so type 2 diabetes tends to run in families. Several genes have been linked to type 2 diabetes, and many are under study related to type 2 diabetes. Risk factors for developing type 2 diabetes include the following:

  • High blood pressure
  • High triglyceride (fat) levels in the blood
  • Gestational diabetes or giving birth to a baby weighing more than 9 pounds
  • High-fat diet
  • High alcohol intake
  • Sedentary lifestyle
  • Obesity or being overweight
  • Ethnicity, particularly when a close relative had type 2 diabetes or gestational diabetes. Certain groups (such as African Americans, Native Americans, Hispanic Americans, and Japanese Americans) have a greater risk of developing type 2 diabetes than non-Hispanic whites.
  • Aging: Increasing age is a significant risk factor for type 2 diabetes. Risk begins to rise significantly at about age 45 years, and rises considerably after age 65 years.

Diabetes 12 Ways Too Much Sugar Harms Your Body Slideshow

Diabetes 12 Ways Too Much Sugar Harms Your Body Slideshow

Sugar is sweet, but too much of it can sour your health. Whole foods like fruits, veggies, dairy, and grains have natural sugars. Your body digests those carbs slowly so your cells get a steady supply of energy. Added sugars, on the other hand, come in packaged foods and drinks. Your body does not need any added sugars.

REFERENCE:

Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.

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