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Lifestyle Risk Factors

About Lifestyle Risk Factors


Tobacco use is the single most preventable cause of death and disease in the United States. Smoking harms nearly every organ of the body. It causes many diseases and reduces the health of smokers in general. Tobacco use causes more deaths each year than all deaths combined from:

  • human immunodeficiency virus (HIV),
  • illegal drug use,
  • alcohol use,
  • motor vehicle injuries,
  • suicides, and
  • murders.

Compared to nonsmokers, smoking is estimated to increase the risk of many different diseases, including:

  • Coronary Heart Disease
  • Respiratory Disease
  • Cancer
  • Reproductive and Birth Outcomes

Although some people who smoke every day are consuming fewer cigarettes per day, even occasional smoking causes harm, and the best option for any smoker is to quit completely. For more information about smoking and for tips on quitting smoking, visit CDC’s Smoking and Tobacco Use Program.

Quit Smoking Now!
You Can Quit. Learn more.

CDC’s Quit Smoking Website

Overweight and Obesity

Overweight and obesity are both labels for ranges of weight that are greater than what is generally considered healthy for a certain height. The terms also identify ranges of weight that have been shown to increase the likelihood of certain diseases and other health problems.

For adults, overweight and obesity ranges are determined by using weight and height to calculate a number called the "body mass index" (BMI). BMI is an estimate of body fat. It is a good gauge of your risk for diseases that can occur with more body fat.

  • An adult who has a BMI between 25 and 29.9 is considered overweight.
  • An adult who has a BMI of 30 or higher is considered obese.

Use the BMI Calculator or BMI Tables to estimate your body fat.

Research has shown that as a person's weight increases to reach the levels referred to as overweight and obesity the risks for the following conditions also increase:

  • Coronary heart disease
  • Type 2 diabetes
  • Cancers (endometrial, breast, and colon)
  • Hypertension (high blood pressure)
  • Dyslipidemia (high total cholesterol or high levels of triglycerides)
  • Stroke
  • Liver and gallbladder disease
  • Sleep apnea and respiratory problems
  • Osteoarthritis (a degeneration of cartilage and its underlying bone within a joint)
  • Gynecological problems (abnormal menses, infertility)

The environment a person lives in may play a role in overweight or obesity. People may make decisions based on their environment or community. For example, a person may choose not to walk to the store or to work because of a lack of sidewalks. Community, home, school, health care, and workplace settings can all influence people's health decisions. Therefore, it is important to create environments in these locations that make it easier to engage in physical activity and eat a healthy diet.

For more information about Overweight and Obesity, visit CDC’s Healthy Weight Program.

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