Obesity is a chronic disease that occurs when your body stores excessive fat. A body mass index (BMI) of 30 or higher shows obesity in adults.
It is a major health problem with fatal consequences. It causes more than 28 million deaths each year. Obesity also contributes to diseases like certain cancers, heart attacks, and diabetes.
According to the US Centers for Disease Control and Prevention (CDC), obesity affects 42.2 percent of American adults.
BMI, on the other hand, is not a good measure of obesity because it has more limitations. As a result, when assessing obesity, the CDC suggests considering other factors such as age, gender, and muscle mass.
This article will cover obesity, its classification, causes, health risks, causes, treatment, and prevention.
How is it classified?
Below is an obesity chart used to classify overweight in adults.
|Less than 18.5||Underweight|
|18.5 to less than 25||Normal|
|25.0 to less than 30||Overweight|
|30 or higher||Obesity|
|30 to less than 35||Class 1 obesity|
|35 to less than 40||Class 2 obesity|
What is childhood obesity?
Obesity in children occurs when their body mass index (BMI) is at or above the 95th percentile of their peers. The CDC states that obesity affects 1 in 5 children in America. CDC classifies childhood obesity using the BMI chart below:
|BMI Range||Weight Status Category|
|Less than 5th percentile||Underweight|
|5th percentile to less than 85th percentile||Normal Weight|
|85th percentile to less than 95th percentile||Overweight|
|95th percentile or greater||Obese|
What causes obesity?
- Genetics: Studies show that over 50 genes may predispose a person to obesity. For instance, Fat mass and obesity-associated genes (FTO) affect your calorie intake. It raises your appetite, allowing you to eat more food.
- Consuming too many calories: If you take in more calories than you burn, you risk becoming obese. Food high in sugars and fats increases your calorie intake, increasing your body fat mass. For instance, a 2019 study shows that those fed on processed foods gained more weight.
- Growing older: When you grow older and become less active, your hormone changes, increasing obesity risk. The growth hormones slow your metabolism, thus weight gain.
- Not sleeping enough: If you don’t get enough sleep, your body produces ghrelin, an increasing appetite hormone. A study shows those who slept for four or fewer hours a night had higher levels of ghrelin, which increased their appetite.
- Medication and weight gain: You may gain weight from medications such as steroids and antidepressants.
- Pregnancy: Gaining more than the recommended weight during pregnancy may lead to obesity.
Health conditions causing obesity
- PCOS (polycystic ovary syndrome): This makes it difficult for your body to use the insulin hormone, which facilitates weight gain.
- Prader-Willi syndrome: A childhood disease that makes you constantly crave food. Hence, leading to rapid weight gain.
- Cushing syndrome: Occurs when you expose your body to high cortisol levels. High cortisol levels increase your appetite, causing you to eat more food.
- Osteoarthritis: A health condition that affects your joints. It causes wear and tear in your joints and cartilages, exposing them to pain. As a result, the pain decreases your walking and exercise abilities, leading to weight gain.
Individuals at risk of obesity
You are at high risk of becoming obese if you:
- Take medicines and drugs that stimulate appetite, making you eat more and put on extra pounds.
- Suffer from diseases like POC and Cushing syndromes that contribute to obesity.
- Have obesity genes such as FTO that predispose you to obesity by increasing your appetite level.
- Suffer from anxiety or stress, which contribute to weight gain. Your body responds to stress by increasing cortisol levels, which gets the body ready to eat more food.
How is obesity detected?
A physician may use various procedures to diagnose obesity. Some of these procedures are:
- Calculating your BMI: A doctor will check your body mass index. If your BMI is 30 or higher, you are obese.
- Measuring your waist circumference: A waist circumference over 35 inches in women and 40 inches among men shows obesity.
- Blood tests: Your doctor may perform various blood tests to determine if you are obese. Some of these tests are the thyroid test, cholesterol test, and glycogen test.
- Checking your health history: For instance, a doctor may check your weight, eating habits, health condition, and stress level.
- A general physical exam: These include random checks of your height, heart rate, temperature, and blood pressure.
- Bioelectric Impedance (BIA): Uses electric current flows to measure obesity.
- Skinfold thickness: A physician measures your skin thickness’s pinch to determine obesity.
What are the health risks associated with obesity?
- Insulin resistance: Occurs when cells in your liver fail to respond to insulin. The excess insulin causes you to produce excess fat, which leads to weight gain. A study shows that high insulin secretion leads to obesity.
- Type 2 (adult-onset) diabetes: Occurs when your blood sugar levels rise. When obese, fatty acids cause your body to fail to use insulin. Excess insulin fails to balance your blood sugar, causing it to rise.
- High blood pressure: Having excess weight increases your blood pressure. It puts more pressure on your arteries, making them resist the blood flow, causing your blood pressure to rise.
- High cholesterol: Being overweight increases your cholesterol level. For instance, the excess LDL builds up in your arteries, causing a blockage.
- A stroke: Occurs when blood flow to your brain stops, causing brain cells to die. Obesity increases your blood pressure, which may cause a stroke.
- Heart attack: Being obese may lead to the build-up of fatty materials in your arteries. When the arteries are clogged and damaged, or when the vessels supplying blood to the heart itself are compromised, a heart attack is likely.
- Congestive heart failure: Obesity leads to functional and structural changes in your heart, which may cause heart failure.
- Arthritis: Occurs when your soft tissues are damaged. The extra weight places pressure on joints, leading to wear and tear.
- Infertility: Occurs when an obese female has high leptin. Leptin produces fatty tissues that may disrupt sex hormones. Hence you may not ovulate.
- Certain cancers: Caused when one cell in your body grows out of control. Research shows that excess body fat cells release hormones that affect cell growth. Abnormal cell growth increases your risk of getting cancers like kidney and esophageal.
- Sleep apnea: A sleeping condition in which you’ve one or more pauses in breathing. The excess fat around your neck makes your airway smaller, making it difficult to breathe.
- Osteoarthritis: A common joint problem that affects your knee, back, and hip. The extra weight places extra pressure on your joints, making them tear away.
How is obesity treated?
Several obesity treatments may help you achieve a healthy weight. Here is how you can treat obesity:
- Weight loss: A natural way to treat obesity. To lose weight, limit your intake of processed foods that are high in calories. Instead, focus on consuming high-fiber foods and whole grains. Some studies have shown that eating more fiber-rich foods may help you lose weight and keep it off.
- Weight loss surgeries: Help you shape and change the function of your digestive system. That is the removal of part of your stomach or small intestines to limit your calorie intake. Some common surgeries include; gastric bypass and sleeve gastronomy.
- Weight loss medicines: Your doctor may prescribe medication to help you lose weight. Commonly prescribed weight-loss medicines approved by the US Foods and Drug Administration for long-term use include: Bupropion-naltrexone (contrive), Orlistat (Xenical), and Phentermine-topiramate (Qsymia)
Most of these drugs, except Orlistat, work by decreasing your appetite. Alternatively, they increase your stomach fullness to help you eat less. Orlistat works by interfering absorption of fat.
Lifestyle and behavioral changes that can help with weight loss
Losing weight safely is often better than losing a lot of weight quickly. However, this kind of progress requires a change in your behavior and lifestyle. Here are some lifestyle changes you can make to help you lose weight fast:
- Dietary Changes: The key to safe weight loss is to adopt healthy eating habits. For instance, eating a well-balanced diet helps you limit your calorie intake. Besides, seek a nutritionist or dietician who will guide you on the best weight loss practices.
- Regular exercising: Helps you lose weight and maintain a healthy weight. Regular exercising can increase your metabolism or the number of calories your body uses. A study conducted in 2018 has shown that those who took part in exercises lost weight. Some activities that burn the most body fat include Crunches aimed at burning belly fat, Cycling, Walking, Swimming, Weight training, and Yoga.
- Weight management programs: A steady weight-loss program is nutritious, safe, sustainable, and effective. Also, a good weight loss program should help you lose about 1-2 pounds a week. Some of the popular weight loss programs include the Mediterranean diet, Jonny Craig, Atkins diet, Ketogenic diet, and Weight watchers
Medications prescribed for weight
If you haven’t lost weight through exercise or diet, your doctor may recommend a weight-loss drug for you.
He may recommend the following obesity medications:
- Phentermine/topiramate: Promotes weight loss by decreasing your appetite
- Naltrexone/bupropion: Promotes weight loss by moderating your appetite
- Liraglutide: Promotes weight loss by decreasing the secretion of insulin, reducing food intake
- Orlistat: Decreases the amount of dietary fat your intestines absorb, hence weight loss
Weight loss surgery
Your doctor may also recommend weight loss or bariatric surgery in cases where lifestyle changes or medications don’t help you shed extra pounds.
Different weight-loss surgeries have been proved to work in helping individuals lose weight.
Below are some of the commonly used surgeries to help you lose weight:-
- Gastric bypass surgery: In this procedure, your surgeon divides your stomach into two parts; the lower and the upper section. He creates a food shortcut by bypassing some parts of the small intestines and stomach. That translates to the absorption of fewer calories, which promotes weight loss.
- Laparoscopic adjustable gastric banding: During this procedure, the surgeon puts a gastric band around your upper stomach. It creates a small stomach punch, which means you eat less.
- Gastric sleeve surgery: During this surgery, your surgeon divides your stomach into two unequal parts. He removes 75% of the curved stomach, leaving you with a narrow sleeve connecting to the small intestines.
- Biliopancreatic diversion with a duodenal switch: The procedure involves two steps. During the first, the surgeon removes 70% of the curved stomach. Then, he cuts through the part of the small intestine below the duodenum.
NOTE: Surgeries are not the best option. For effective and long-lasting results, combine surgeries with exercising and healthy eating habits.
Best candidates for weight loss surgery
Weight loss surgery may be good for you if:
- You have a BMI equal to or greater than 40.
- Your BMI is equal to or greater than 35, and you have any obesity-related health risks.
- You’re unable to achieve a healthy weight despite weight loss efforts.
How to prevent obesity
There is no simple solution to obesity in both adults and children. The best way is to adopt healthy lifestyle changes. Here are some of the changes:
- Healthy eating habits: Eating nutritious food helps you lose weight. Choose to eat foods like whole grains, fruits, vegetables, and lean proteins.
- Physical activities: Aim to exercise for at least 20- 30 minutes daily. For example, exercises like walking, yoga, swimming, or running may help you lose weight.
- Assess your weight: Visit your doctor at least once a year to check your weight and see if you’re at risk of being obese.
There are many known causes of obesity, such as diseases and genetics. If you recognize any of these, take action to address the cause. Failure to address the cause may expose you to cancers, diabetes, and heart diseases.
Further, your doctor may recommend weight-loss surgeries or medications to treat obesity. However, a healthy diet full of fresh foods and regular exercises helps you reduce obesity risks.
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- National Institute of Diabetics and Digestive and Kidney Diseases (n.d). Treatment for Overweight & Obesity. niddk.nih.gov/health-information/weight-management/adult-overweight-obesity/treatment
- Centers for Disease Control and Prevention, & Centers for Disease Control and Prevention. (2016). Defining adult overweight and obesity. cdc.gov/obesity/adult/defining.html
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