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What is the Meaning of Obesity?

A chronic, relapsing, multi-factorial, neurobehavioral disease, when there is an increase in body fat regulates the dysfunction of adipose tissue and abnormal fat, that results in adverse effects on the health which includes metabolic, biomechanical, and psychosocial consequences, the above mentioned is the obesity medical definition. 

In 1998, the National Institutes of Health declared obesity a disease. In simple words, the meaning of obesity is as follows: “Overweight”. Let us learn what causes obesity, what are the medical complications and how to prevent it?

Short Note on Obesity

Obesity is identified when the body mass index (BMI) is equal to 30 or greater than that. The body mass index can be calculated easily by dividing the body weight by squaring the height. But the BMI alone cannot estimate body fat but it is considered as one of the factors.

Obesity meaning is as follows, it is a complex disease involving an excessive amount of body fat. Obesity isn't just a cosmetic concern. It is a medical problem that will increase the risk of getting affected with other diseases such as heart attack, diabetes, and certain cancers. Usually, obesity is caused by a combination of inherited factors, that are combined with the environment and exercise choices and personal diet.


Although there are genetic, behavioral, metabolic, and hormonal influences on weight, obesity occurs once you absorb more calories than you burn through exercise and normal daily activities. Your body stores these excess calories as fat. People might eat more calories before feeling full, feel hungry sooner, or eat more during stress or anxiety.

Risk Factors

1. Family Inheritance and Influences: The genes that we get from our parents may affect the amount of fat stored in our body, and where that fat is distributed. Obesity tends to run in families which is not just because of the genes they share but because of similar eating and activity habits.

2. Food Habits: A diet that's high in calories, lacking in fruits and vegetables, filled with nutrients, and laden with high-calorie beverages and oversized portions contributes to weight gain. Liquid calories such as alcohol, soft drinks, high-calorie beverages etc. If a person has a sedentary lifestyle, he can easily take in more calories every day than he burns through exercise and routine daily activities. Looking at a computer, tablet, and phone screen may be a sedentary activity. The number of hours a person spends in front of a screen is highly associated with weight gain.

3. Age: Obesity can occur at any age, even in young children and as a person ages, hormonal changes and a less active lifestyle increases the risk of obesity. In addition, the quantity of muscle in your body tends to decrease with age. The lower muscle mass can result in a decrease in metabolism. These changes also reduce calorie needs and may make it harder to stay off excess weight.

4. Diseases: Many health conditions can lead to weight, and in turn obesity. And obesity can further aggravate the conditions, creating a vicious cycle of weight gain. Diseases such as hypothyroidism, insulin resistance, polycystic ovary syndrome, and Cushing's syndrome are known to be contributors to obesity. 

4. Other Factors:

  • Pregnancy: Weight gain is common during pregnancy hence the women find it difficult to lose weight after the baby is born. This weight gain may contribute to the event of obesity in women. Breast-feeding could also be the simplest choice to lose the load gained during pregnancy.

  • Quitting Smoking: When people quit smoking, they will consume more food to fulfill the cravings that in turn results in weight gain. At the end of the day, however, quitting smoking remains a greater benefit to your health than is constant smoke. Your doctor can assist you to prevent weight gain after quitting smoking.

  • Sleep: Not having enough sleep or sleeping for too much time can cause changes in hormones that increase your appetite.

  • Negative Emotions: Things like boredom, sadness, or anger, can have a huge influence on eating habits, leading to the intake of high calories.

  • Stress: Many external factors that affect your mental health and well-being may contribute to obesity. When people are in stressful situations, they often consume high-calorie food.


People with obesity are more likely to develop a variety of probably serious health problems, including:

  1. Heart Disease and Strokes: Obesity causes you to be more likely to possess high vital signs and abnormal cholesterol levels (high LDL cholesterol, low HDL cholesterol, or high levels of triglycerides), which are risk factors for heart condition and strokes. 

  2. Type 2 Diabetes: Our body uses insulin to regulate blood glucose levels which can affect obesity. It raises the risk of resistance to insulin and diabetes.

  3. Digestive Problems: Obesity increases the likelihood that you're going to develop heartburn, gallbladder disease and liver problems.

  4. Gynecological and Sexual Problems: Obesity can also cause infertility and irregular periods in women. Obesity also can cause erectile dysfunction in men.

  5. Osteoarthritis: Obesity increases the strain placed on weight-bearing joints, causing inflammation within the body. This may cause problems like osteoarthritis.

  6. Hypertension: Obesity makes your heart work harder to pump blood through your body. All this extra effort puts strain on the arteries. The arteries, in turn, resist this flow of blood, causing the rise in blood pressure or hypertension. Obesity and hypertension combined are a leading cause of cardiovascular disease.  

  7. Sleep Apnea and Breathing Problems: Fat deposits in the upper respiratory tract narrow the airway, resulting in a decrease in muscle activity in this region. This could lead to hypoxic and apneic episodes, resulting in sleep apnea.

  8. Mental Illness: It could also contribute to mental illnesses such as clinical depression, anxiety, and other mental disorders.

  9. Gallbladder Disease: In obesity, the hypersecretion of cholesterol causes local secretion of fat, leading to gallbladder disease. 

  10. Severe COVID-19 Symptoms: Obesity increases the danger of developing severe symptoms if you become infected with the virus that causes coronavirus disease 2019 (COVID-19). People who have severe cases of COVID-19 may require treatment in medical care units or maybe mechanical assistance to breathe.


As per the obesity definition, being overweight is caused due to overeating. By following certain steps, we can control being overweight. They are as follows: daily exercise, a healthy diet, and a long-term commitment to watch what you eat and drink.

  1. Exercise Regularly: You need to urge 150 to 300 minutes of moderate-intensity activity every week to stop weight gain. The physical activities include walking fastly and swimming.

  2. Follow a Healthy-Eating Plan: specialize in low-calorie, nutrient-dense foods, like fruits, vegetables, and whole grains. Avoid saturated fat and limit sweets and alcohol. Eat three regular meals in a day with limited snacking, during this you can enjoy the high-calorie desserts or beverages in small quantities.

  3. Avoid the Traps that Cause you to Eat: Identify situations that trigger out-of-control eating. You can plan and develop strategies for handling these sorts of situations that will make you eat more and stay on top of your eating behaviors.

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FAQs on Obesity

1. What is the Meaning of Obesity? What are the Causes of Obesity?

Obesity meaning is given as it is a complex disease that involves an excessive amount of body fat.

The causes of obesity are as follows:

  • Genetics

  • Junk foods

  • Food addiction

  • Hormonal imbalance

2. What is Meant By Obesity? Write Down the Obesity Definition in Biology.

Obesity’s definition is as follows, it is a complex disease involving an excessive amount of body fat. 

According to Biology, obesity can be defined as a state of excess mass of adipose tissue in the body.

3. What is the difference between being overweight and obese?

Both overweight and obese are terms meaning that the body fat is more than what is considered healthy. Both are used to identify people who are at risk for health problems owing to the body fat percentage. The only difference is that the term obese generally means a much higher amount of body fat than overweight.

The body needs fat for energy, heat insulation, and other bodily functions. But the more fat the higher the risk of health problems can be. The health problems that could stem from excess body fat are diabetes, kidney disease, heart disease, and other problems.

So the only difference is that those who are obese are at slightly more risk than those who are overweight. 

4. What are the World Health Organization (WHO) standards for obesity?

The World Health Organization (WHO) states that the Body Mass Index (BMI) provides the most useful measure of overweight and obesity as it is the same for both sexes and for all ages of adults. But it is only a rough guide because it may not correspond to the same degree of fatness in different individuals.

WHO defines overweight and obesity as follows.

  • For Adults

Overweight is a Body Mass Index BMI greater than or equal to 25.

Obesity is a BMI greater than or equal to 30.

  • For Children

Age is considered when defining overweight and obesity. For children under 5 years of age, overweight is weight-for-height greater than 2 standard deviations above WHO Child Growth Standards median. And obesity is weight-for-height greater than 3 standard deviations above the WHO Child Growth Standards median.

5. How can one correct obesity?

It is extremely crucial to come down to a healthy weight and achieve roughly the ideal BMI to correct obesity. And weight loss requires three components to be successful - diet, exercise, and behavior modification. 

  • Diet: Maintaining a balanced diet that’s rich in nutrition and offers your body only the required amount of calories. According to most experts, a steady weight loss of about one pound a week is the safest way to lose weight. 

  • Regular Exercise: Consistent exercise such as brisk walking, running, swimming, biking, dancing or any other that is suitable, are crucial to burn the extra fat. The amount of exercise required to lose weight differs from person to person, based on their metabolism. 

  • Behavior Modification: Changing your unhealthy daily habits and behavior patterns are crucial. Behavior modification techniques like keeping a food diary, shopping from a list and not when you're hungry, or bypassing the stores/restaurants that tempt you to eat unhealthy etc. are very helpful. 

  • Root Cause: It is important to understand if any hormonal or other physical conditions are the root cause of obesity. And treating the root cause often plays a crucial role in taking corrective measures.

  • It is recommended to see a doctor for customizing your weight loss plan based on your health conditions, body type, age and other nutritional factors.