Understanding excess weight and its role in type 2 diabetes

This article is designed to help you better understand the impact of excess weight and its role in type 2 diabetes. Excess weight, obesity and morbid obesity are all risk factors for developing type 2 diabetes. Often times, individuals are not aware of the health risk of excess weight until they are diagnosed with pre-diabetes or type 2 diabetes.

What is type 2 diabetes?

Type 2 diabetes is a chronic, potentially debilitating and often fatal medical condition requiring regular monitoring of an individual's blood sugar level and treatment. In type 2 diabetes, the body either does not properly produce or use insulin, a hormone produced by the pancreas that helps move sugar into cells. Therefore, the body becomes resistant to insulin. This resistance causes high blood sugar levels.

What are the complications of high blood sugar levels?

Excess sugar in the blood causes many health-related problems. The cells cannot get enough of the sugar they need, and when sugar levels in the blood become too high, it causes damage to nerves and blood vessels, usually in the heart, feet, hands, kidneys and eyes. Other complications of high sugar and insulin resistance include:

  • Increased risk of heart disease and stroke
  • Neuropathy (nerve damage, especially in extremities)
  • Nephropathy (renal impairment, kidney failure)
  • Retinopathy (vision problems, blindness)
  • Cardiovascular disease (heart disease and increased risk of stroke)
  • Erectile dysfunction in men and decreased sexual desire in both men and women
  • Depression
  • Amputation

How does excess weight impact type 2 diabetes?

Excess weight can greatly affect your health in many ways, with type 2 diabetes being one of the most serious. There are many forms of measurement used to evaluate someone's excess weight; however, the most commonly-used method is calculating your body mass index (BMI).

BMI is a number calculated by dividing a person's weight in kilograms by his or her height in meters squared. BMI is a useful tool used in determining the degree of an individual's excess weight. There are five weight status categories that you may fit into:

  • Underweight
  • Normal weight
  • Overweight
  • Obese
  • Morbidly obese

When an individual predisposed to diabetes has excess weight, the cells in the body become less sensitive to the insulin that is released from the pancreas. There is some evidence that fat cells are more resistant to insulin than muscle cells. Individuals affected by type 2 diabetes who exercise appear to reduce the severity of insulin-resistance because the exercising muscles use the extra sugar found in the blood; therefore, the body does not secrete insulin and the sugar is no longer diverted to excess fat cells.

It's not just how much an individual weighs, but also where they carry the weight that puts them at greater risk for health problems. Individuals carrying more weight around their waist (apple-shaped) are more likely to suffer from obesity-related conditions than someone who carries more weight in their hips and thighs (pear-shaped).

Individuals affected by excess weight, particularly obesity and morbid obesity, are more likely to develop type 2 diabetes as a related condition of their excess weight. Obesity and morbid obesity greatly increase your risk of having heart disease, type 2 diabetes, certain types of cancer, sleep apnea, osteoarthritis and much more.

Are you at risk for type 2 diabetes?

What you consume throughout your day and how active you are affects your risk of developing type 2 diabetes. Being overweight (BMI of 25-29.9), or affected by obesity (BMI of 30-39.9) or morbid obesity (BMI of 40 or greater), greatly increases your risk of developing type 2 diabetes. The more excess weight you have, the more resistant your muscle and tissue cells become to your own insulin hormone. More than 90% of people with type 2 diabetes are overweight or affected by a degree of obesity.

In addition to excess weight, there are many other factors that increase your risk of developing type 2 diabetes, such as:

Sedentary lifestyle

Inactivity and being overweight go hand-in-hand with a diagnosis of type 2 diabetes. Muscle cells have more insulin receptors than fat cells, so an individual can decrease insulin resistance by exercising. Being more active also lowers blood sugar levels by helping insulin to be more effective.

Unhealthy eating habits

Unhealthy eating is a contributor to obesity. Too much fat in your diet, not enough fiber and too many simple carbohydrates all contribute to the development of type 2 diabetes.

Family history and genetics

It appears that people who have family members with type 2 diabetes are at a greater risk for developing it themselves. Asians, Pacific Islanders, American Indians, Alaskans, African Americans and Hispanics all have a higher than normal rate of type 2 diabetes.

Increased age

As we age, the risk of type 2 diabetes becomes greater. Even if an elderly person is thin, they still may be predisposed to developing diabetes. The pancreas ages right along with us and doesn't pump insulin as efficiently as it did when we were younger. As our cells age, they become more resistant to insulin as well.

High blood pressure and high cholesterol

These two factors are the hallmark risk factors for many diseases and conditions, including type 2 diabetes. Not only do they damage heart vessels, but they are two key components in metabolic syndrome, a cluster of symptoms including obesity, a high fat diet and lack of exercise. Having metabolic syndrome increases the risk of heart disease, stroke and type 2 diabetes.

History of gestational diabetes

Women affected by obesity are more insulin resistant when compared to women of normal weight. When pregnant, gestational diabetes generally lasts the duration of pregnancy and approximately 5-10% of females with gestational diabetes will continue to be diabetic after delivery.

How do you test for type 2 diabetes?

There are a variety of blood tests that may indicate whether you have type 2 diabetes. Let's take a look at each test and see what different results could mean for you and your health.

Blood sugar level chart

Blood sugar level HGbA1cIndicates
Under 100 mg/dLNormal
100 to 125 mg/dLPre-diabetes
126 mg/dL or higher on 2 separate testsDiabetes

Fasting blood sugar test

The amount of sugar in your blood naturally fluctuates but stays within a normal range. The preferred way to test your blood sugar is after you've fasted overnight for at least eight hours. A fasting blood sugar level less than 100 milligrams of sugar per deciliter of blood is considered normal.

Symptoms that you may be developing or have type 2 diabetes

  • Frequent urination
  • Increased thirst
  • Unplanned weight-loss
  • Weakness and fatigue
  • Numbness or tingling in hands, legs or feet
  • Blurred vision
  • Dry, itchy skin
  • Frequent infections
  • Slow healing of cuts and bruises

If your blood sugar level measures from 100 to 125, you have impaired fasting glucose, and this may be an indication that you have pre-diabetes. If your blood sugar level is above 200 mg/dL, with symptoms of diabetes (see below), a second test may not be necessary to reach the diagnosis.

Random blood sugar test

This test is done without any special preparation, such as fasting overnight. Even if you've recently eaten and your blood sugar level is at its peak, the level shouldn't be above 200 mg/dL. If it is and you also have symptoms of type 2 diabetes, you can expect a diagnosis of type 2 diabetes.

Oral sugar tolerance test

This test requires you to visit a lab or a healthcare professional after at least an eight-hour fast. At the office or lab, you will drink about eight ounces of a sweet liquid that contains a lot of sugar (about 75 grams). Your blood sugar level will be measured before you drink the liquid, then after one hour and again after two hours. If your blood sugar level is 200 mg/dL or above after two hours, you may have diabetes.

What can you do to improve your health and prevent type 2 diabetes?

Losing weight is one of the most beneficial ways you can help prevent type 2 diabetes. Moderate and sustained weight loss (5-10% of body weight) can improve insulin action and decrease fasting sugar concentrations.

For many individuals, simply adjusting their caloric intake and beginning an exercise program can greatly improve their type 2 diabetes and overall health.

Healthy meal plan

Weight loss occurs when energy expenditure exceeds energy intake. Creating a calorie deficit will result in weight loss. Writing down the food, portion size and calorie amount in a food diary will help you become aware of the foods you consume and provide objective evidence of calorie intake.

Exercise program

Regular exercise helps maintain weight loss and prevent weight regain. It also improves insulin sensitivity and glycemic control (measurement of the effects of carbohydrates on blood sugar level) and may decrease the risk of developing type 2 diabetes.

A goal should be set for 30 to 45 minutes of moderate exercise five times per week. The exercise does not need to occur in a single session to be beneficial. Dividing the activity into multiple and short episodes produces similar benefits and can enhance compliance.

What can you do to learn more about type 2 diabetes and excess weight?

The Obesity Action Coalition (OAC) is the only nonprofit organization whose sole purpose is representing those affected by obesity. The OAC offers many valuable educational resources discussing excess weight, obesity, morbid obesity, type 2 diabetes and much more.

To see if you are at risk for type 2 diabetes, please schedule a visit with a healthcare professional for more information. To help you prepare for your visit, we've provided you with some great sample questions that you may be asked by a healthcare professional and sample questions for you to ask a healthcare professional.

Sample questions

Questions a healthcare professional may ask you

  • When was the last time you saw a healthcare professional?
  • When did you last have blood work completed?
  • Are you currently taking any medications?
  • Have you been previously diagnosed with any medical conditions?
  • How physically active are you on a weekly basis?
  • Can you describe your eating habits?
  • Does anyone in your family have type 2 diabetes?
  • Do you feel fatigued or tired more than usual?
  • Do you have a dry mouth or find yourself drinking fluids often?
  • Do you find yourself urinating often?
  • Do you have blurred vision or experience headaches?
  • Have you recently gained weight?

Questions for your healthcare professional

  • Do you have special training in treating diabetes?
  • Do you have special training in obesity?
  • Does your office have a registered dietitian on staff with type 2 diabetes and obesity training?
  • Do you have diabetes educators available?
  • What kind of tests do you use to determine if I have type 2 diabetes?
  • How do you prefer to treat someone with type 2 diabetes?
  • Am I at risk for any complications associated with type 2 diabetes?

© 2011 Obesity Action Coalition (OAC)