Obesity is a condition in which a person has accumulated much more fat than normal, and the level of weight has become a real burden, both medically and socially.
Overweight or obese?Edit
When a person is "overweight", it means that they have more body fat than they need for their body to function. It's very common for people to be overweight, especially in developed countries where there's a plentiful food supply, and people have sedentary lifestyles that don't involve much exercise. A 2002 study has indicated that as much as 64% of the adult US population is overweight, and this number is increasing. 
"Obesity" is the point at which the level of body fat is associated with increased risk for serious medical conditions, including:
- Type 2 diabetes
- Heart disease and high blood pressure
- Joint pain
- Back pain
- Difficulty during pregnancy
- Kidney and liver problems
- Breathing problems during sleep
Body Mass Index, or BMI, is a simple and widely used method for estimating body fat.  The Body Mass Index is calculated using height and weight, either in pounds/inches or kilograms/meters: (BMI = kg/m²) or (BMI = lbs*703/inches²).
The absolute waist circumference (>102 cm in men and >88 cm in women) or waist-hip ratio (>0.9 for men and >0.85 for women) are also used as measures of obesity. It may be explained in a slightly different way by looking at the image on the right hand side. From left to right, as labeled in the image, the "healthy" man has a 33 inch (84 cm) waist, the "overweight" man a 45 inch (114 cm) waist, and the "obese" man a 60 inch (152cm) waist.
The most obvious cause of obesity is overeating, combined with a sedentary lifestyle. One is taking in more energy (calories) through food but expending less energy in activity, and the surplus calories get converted into fats and stored in the body.
There may be more deep rooted and not easily understood reasons for obesity, including:
- Genetic causes – obesity runs in some families, and requires regular care to avoid obesity.
- Certain medical conditions may cause obesity, including hypothyroidism.
- Eating disorders which result in an excessive craving for foods.
- Very sedentary lifestyle.
- Sleeping disorders and mental stress.
- People often gain weight when they quit smoking, although the effect is usually temporary, and the weight returns to normal once the non-smoking habit stabilizes.
- Keep your body active. Take a brisk walk, use stairs if not for going up than for climbing down, play with the children, do household chores like washing and cleaning.
- Reduce the amount of time you spend in sedentary activities, like watching TV.
- Assess your eating habits. Crash diets won't lead you anywhere, and will bring you back to the same level. The key is changing your food habits – reducing high calorie and fatty food, and substituting them with more salads and fruits. Use less sugar and salt too. Food with less salt will make you eat less and is good for general health. Try to reduce the portion sizes, and give sufficient time to eating -- grabbing food is a bad way to eat. Eating peacefully and slowly reduces the urge to eat more as you enjoy your food.
You should always consult with your doctor and dietitian to give you a plan to follow. Please remember, they can give a plan, but you have to implement the plan -- you have to follow through. Changing your diet and your daily activity is a tough, long-term task -- but making those changes will keep you feeling healthy and strong.
- World Health Organization - Obesity pages
- some great ideas on how to lose some weight
- Diet, Nutrition and the prevention of chronic diseases (including obesity) by a Joint World Health Organization/Food and Agriculture Organization Expert consultation (2003). Summary by GreenFacts.org.
- Obesity - a page from the site of Mayo Clinic
- kid weight loss ideas Our kids are fatter than ever how can we stop it?
- ↑ Katherine M. Flegal, PhD; Margaret D. Carroll, MS; Cynthia L. Ogden, PhD; Clifford L. Johnson, MSPH (2002). "Prevalence and Trends in Obesity Among US Adults, 1999-2000". JAMA 288 (14): 1723–1727. .
- ↑ Mei Z, Grummer-Strawn LM, Pietrobelli A, Goulding A, Goran MI, Dietz WH. Validity of body mass index compared with other body-composition screening indexes for the assessment of body fatness in children and adolescents. Am J Clin Nutr 2002;75:978-85. PMID 12036802.