Understanding
Overweight and Obesity

If you have excess body fat, you may be overweight or even obese. These conditions are more than “plumpness” and are the leading cause of disease and death worldwide. 

Obesity is usually multifactorial: it combines your genetics with unhealthy lifestyle/ environmental factors, namely your diet and physical activity. 

If you are overweight or obese you have increased risk of developing serious health conditions like heart disease, diabetes, high blood pressure, stroke, and osteoarthritis. However, even modest weight loss can improve or prevent these health problems. This can usually be achieved by changing your diet and increasing your physical activity. 

In consultation with your healthcare provider, if it is indicated, prescription medications or weight-loss procedures may also be required to lose weight. 

What is overweight and obesity

There is no predefined definition, or easy way to tell if someone’s weight is not healthy, but to clinically assess someone to know which weight loss technique may be best, a starting point must be defined. The problem arises in that there are many parameters to be taken into consideration when assessing someone’s weight, such as your, height, body type, age, gender, the size of your bones, muscle mass and many more. To make assessment easier, the parameters of what is believed obese has been combined. 

This main measure of obesity is referred to as body mass index, or BMI. In simple terms your BMI is calculated by dividing your weight in kilograms by the square of your height in metres. So, if you are 1.7 metres tall and weigh 70 kilograms, then your BMI would be 24.2 [70 ÷ (1.7×1.7)]. 

According to the global predefined BMI standards, a person with a healthy body weight has a BMI value from 18.5 to 24. Based on these standards, you are: 

Underweight: BMI is less than 18.5 

Overweight: BMI is from 25-29 

Obese: BMI is from 30-39 

Very obese: BMI is greater than 40 

For most people, BMI provides a reasonable estimate of body fat. However, BMI does not directly measure body fat, so, some people, such as muscular athletes, may have a BMI in the obesity category even though they do not have excess body fat. 

Apart from BMI there are other factions to reckon within the domain of obesity. There is this entity called central obesity or visceral obesity, which is thought by many to be the real culprit in causing health problems in people with overweight and obesity. You may therefore find it useful to use a measure of your waist or hip circumference, or a ratio of the two, to determine whether you are carrying too much weight. In summary, you have a higher risk of obesity-related conditions if: 

You are a man with a waist circumference more than 101,6 centimetres 

Are a non-pregnant woman with waist circumference more than 88,9 centimetres. 

These measurements indicate that you have central obesity, or visceral/abdominal obesity, that is strongly associated with the increased risk of metabolic conditions, like diabetes, and coronary artery disease. 

What are the causes of obesity?

The World Health Organisation estimates that the rate of obesity has tripled since 1975. In 2016, almost 2 billion adults were overweight, 650 million of whom were obese. In the same year, the Heart and Stroke Foundation of South Africa estimated that about two thirds of women (65.1 %) and almost one third of men (31.2 %) were overweight or obese in South Africa, while 40.1 % of women were estimated obese compared to 11.6 % of men. 

Lifestyle

The rising rates of obesity worldwide are attributed to “obesogenic” environments: an environment with high-calorie foods and diets and corresponding limited physical activity. 

Our body needs fuel to perform our daily activities – fuel in form of calories. Calories are nothing but the unit measuring the energy content of a food. Eating too much of these calories without doing sufficient exercise to burn them causes obesity and overweight. 

Simply, you get energy or calories from food and drinks. This energy is called energy IN. Your body needs a certain amount of energy for activities like breathing, digestion and being physically active. This energy is called energy OUT. When energy IN is more than energy OUT, you gain weight. In the similar way when the energy OUT is more that energy IN, you lose weight. If you want to maintain the same weight, your energy IN and OUT should be equal. In other words, your weight is determined by balancing your energy needs. 

It is worth stating again that the two major contributors to overweight and obesity are: 

Unhealthy diets: These are diets rich in calories and high-fat foods. Saturated fats in red meats, hard butter and fried foods are particularly high in calories and bad for the 

body. Sweets and drinks (like soft drinks) are also very high in sugar and play a large role in adding to your calorie intake. 

Lack of physical activity: Sedentary lifestyles, as associated with large amounts spent sitting at desks and in front of screens, contributes significantly to obesity development and poor health. 

In these regards, your environment can also encourage obesity. Lack of parks, trails, sidewalks and affordable gyms makes it hard for people to be physically active. Additionally, due to busy work schedules, you may not have time to be physically active. While, on the other hand, over-sized food portions also contribute to obesity and overweight. Due to fast-paced lifestyles, people are now more surrounded by huge food portions in restaurants, fast food places, gas stations, movie theatres, supermarkets and in the home. Eating large portions means too much energy intake. Over time, this will cause weight gain if it not balanced with physical activity. 

 

Genetics

Obesity definitely runs in families. Identical twins usually maintain weight levels within 1 kg of each other throughout life even when they live in different, yet similar, environments. While this might result partly from eating habits engendered during childhood, it is generally believed that this close similarly between twins is genetically controlled. However, only one gene is singularly associated directly with obesity in less than 5 % of people. 

Obesity is mostly caused by the interplay of multiple genes and your environment. 

 

Other factors that cause overweight and obesity include:

• Age: As you age, you lose muscle mass and gain fat tissue as your metabolism slows. This does not cause obesity as such, but makes it much easier to develop. 

• Smoking, along with poor diet, low physical activity and excessive alcohol usage: These unhealthy lifestyle behaviours contribute to the development of obesity. 

• Poor sleep: A lack of sleep may cause you to gain weight. 

• Mental health conditions, like depression, and other diseases such as osteoarthritis associated with pain may lead to a decrease in physical activity and hence, an increase in weight. 

• Hormonal imbalances such as caused by polycystic ovarian syndrome (an imbalance in reproductive hormones in women), Cushing’s syndrome (excessive cortisol production) and hypothyroidism (an under-active thyroid). 

How to manage your weight?

If you are at a healthy weight or are overweight and would like to lose weight, you can avoid obesity by following a healthy lifestyle, including: 

1. Eat a healthy diet low in fat This is crucial to reducing your calorie intake. A diet high in saturated and trans-fats are packed with calories. Saturated fats are found in fatty, red meats, and hard fats like butter, but also in chicken skin, hard dairy products, cream and coconut oil, while fried foods are high in trans-fats. It is very important that you replace these with foods that are high in healthier mono-unsaturated and polyunsaturated fats such as plant oils, peanut butter, nuts and seeds, avocado, fish and lean chicken. Try to avoid frying food by using healthier cooking methods like baking, boiling and roasting. Also try to focus on eating more fruits and vegetables high in fibre that can make you feel fuller for longer. It is recommended that you eat five fruit and vegetables per day to stay healthy. See Cooking from the Heart for delicious, heart-healthy recipes and about how to make healthier meat choices, use healthy cooking methods and how to incorporate more fruit and vegetables into your diet.

2. Exercise Try to keep as active as possible. You don’t have to join a gym do this; instead, just take regular walks, ride a bike or dance along to the music on your radio. Your goal should be 30 minutes of moderate activity (makes you sweat and your heart beat a little faster) most days of the week. Also include doing some vigorous/high-intensity aerobic exercise to easily manage your weight and keep your heart healthy. Regular physical activity also reduces the risk of heart disease and stroke and helps alleviate stress. 

3. Limit your alcohol consumption As excess alcohol consumption can contribute to weight gain, consider limiting your alcohol intake. 

4. Manage stress Unfortunately, as stress can contribute to weight gain by increasing cortisol levels, try to find effective stress management techniques like mindfulness, meditation, yoga and deep breathing. 

How to lose weight for health?

If you are overweight or obese, you will need to lose weight. Consult your healthcare practitioner about how best to do this. 

In general, slow but steady weight loss (of 0.5 kg-1.0 kg per week) is the most successful way to lose maximum weight and keep it off. This is achieved by a focus on a healthy and balanced diet and regular physical activity as part of an ongoing healthy lifestyle. Try to find and stick to a consistent healthy-weight plan that you know you can follow sustainably and that you can afford. 

It is also important to regularly monitor your weight and track your weight loss, such as by using a weight scale.

Counselling or weight-loss support groups can also encourage you to stick to your healthy behaviour changes, and will offer help in your weight-loss process. 

Are there treatments available for weight loss and obesity?

When healthy eating and physical activity habits are not enough, your doctor may prescribe medicines to treat overweight and obesity. An example of a prescription weight-loss medication is phentermine which can help suppress your appetite. 

You must to stick with your healthy-eating plan and continue getting regular physical activity while taking weight-loss medicines. 

You may see advertisements for herbal remedies and dietary supplements for weight loss. Some of these supplements may have serious side-effects. Therefore, talk with your doctor before taking any over-the-counter herbal remedies or dietary supplements for the purpose of trying to lose weight. 

Bariatric surgery includes several types of operations that help you lose weight by making changes to your digestive system, especially the stomach. Bariatric surgery may be an option if you have extreme obesity and have not been able to lose enough weight to improve your health or keep gaining back the weight you lost with other treatments. 

What are the complications of overweight and obesity?

Overweight and obesity increase the likelihood of developing a number of potentially serious health problems, including: 

High blood pressure, high cholesterol, heart disease and stroke: Obesity causes triglyceride to be deposited in adipose (fatty) tissues. This unhelpfully increases your body’s demand for nutrients and oxygen which, in turn, increases the amount of blood circulating throughout the body. This increased amount of blood increases the pressure on the blood vessels walls causing high blood pressure. Additionally, when HDL and LDL cholesterol get deposited on the walls of blood vessel, it causes them to become damaged and narrowed, decreasing the flow of blood through. 

Type 2 diabetes: Blood sugar increases due to obesity. This is because the insulin that regulates the sugar level in blood does not get entry due to the body’s fat cells, hence you can become insulin resistant. 

Digestive problems: These include: indigestion, heartburn, gastroesophageal reflux (GERD), gallstones, pancreatitis and fatty liver disease. 

Osteoarthritis and other degenerative bone diseases: Obesity increases the stress placed on weight-bearing joints, like the hips and knees, in addition to promoting inflammation within the body. 

Gynaecological problems and sexual dysfunction: Obesity may cause infertility and menstrual irregularities in women and erectile dysfunction in men. 

Sleep apnoea: If you have obesity then you are more likely to have sleep apnoea, a potentially serious disorder in which breathing repeatedly stops during sleep. 

Certain cancers. Obesity may increase the risk of developing the following cancers: uterine, cervical, endometrial, ovarian, breast, colon, rectum, oesophageal, liver, gallbladder, pancreas, kidney and prostate. 

Mental problems: These can be linked to feelings of shame and isolation due to obesity that may cause depression. 

Severe COVID-19 disease: Obesity increases the risk of developing severe COVID-19 symptoms if you become infected with the virus that cause coronavirus disease 2019 (COVID-19). 

Sources

Centers for Disease Control and Prevention. (2020) Assessing Your Weight. US CDC. Available from: https://www.cdc.gov/healthyweight/assessing/index.html [Accessed April 16, 2021] 

• Centers for Disease Control and Prevention. Adult Obesity Causes and Consequences. US CDC. Available from: https://www.cdc.gov/obesity/adult/causes.html [Accessed April 16, 2021] 

• Mayo Clinic staff. (n.d.) Obesity: Symptoms and Causes. Mayo Clinic. Available from: https://www.mayoclinic.org/diseases-conditions/obesity/symptoms-causes/syc-20375742#:~:text=Obesity%20is%20a%20complex%20disease,blood%20pressure%20and%20certain%20cancers. 

• Mayo Clinic staff. (n.d.) Obesity: Diagnosis and Treatment. Mayo Clinic. Available from: https://www.mayoclinic.org/diseases-conditions/obesity/diagnosis-treatment/drc-20375749 

• Moores, D. (2020) Obesity. Healthline. Available from: https://www.healthline.com/health/obesity#complications [Accessed April 16, 2021] 

• The World Health Organisation. (n.d.) Obesity. WHO Global. Available from: https://www.who.int/health-topics/obesity#tab=tab_1 [Accessed April 16, 2021] 

• Schousebou, JT., et al. (2018) Central Obesity and Visceral Adipose Tissue Are Not Associated With Incident Atherosclerotic Cardiovascular Disease Events in Older Men. J. Am. Heart. Assoc. 2018;7:e009172. https://doi.org/10.1161/JAHA.118.009172 

Global stats: The World Health Organisation. (2021) Obesity and overweight. WHO Fact sheets. Available from: https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight [Accessed June 15, 2021] 

Data: The Heart and Stroke Foundation South Africa. (2016) Cardiovascular Disease Statistics Reference Document. Available from: http://www.heartfoundation.co.za/wp-content/uploads/2017/10/CVD-Stats-Reference-Document-2016-FOR-MEDIA-1.pdf [Accessed April 16, 2021]

• Centers for Disease Control and Prevention. (2013) Genes and obesity. US CDC. Available from: https://www.cdc.gov/genomics/resources/diseases/obesity/obesedit.htm [Accessed April 16, 2021] 

• Centers for Disease Control and Prevention. (2020) Losing weight. US CDC. Available from: https://www.cdc.gov/healthyweight/losing_weight/index.html [Accessed April 16, 2021] 

• Chiolero, A., Faeh, D., Paccaud, F., Cornuz, J. (2008) Consequences of smoking for body weight, body fat distribution, and insulin resistance. Ame J. Clin. Nut. 87;4:801–809. DOI: https://doi.org/10.1093/ajcn/87.4.801 

• Traversy, G., & Chaput, J. P. (2015). Alcohol Consumption and Obesity: An Update. Current obesity reports, 4(1), 122–130. DOI: https://doi.org/10.1007/s13679-014-0129-4 

Shah, M. (2020) Is phentermine a good option for weight loss? Mayo Clinic. Available from: https://www.mayoclinic.org/healthy-lifestyle/weight-loss/expert-answers/phentermine/faq-20057940 

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Sources

Centers for Disease Control and Prevention. (2020) Assessing Your Weight. US CDC. Available from: https://www.cdc.gov/healthyweight/assessing/index.html [Accessed April 16, 2021] 

• Centers for Disease Control and Prevention. Adult Obesity Causes and Consequences. US CDC. Available from: https://www.cdc.gov/obesity/adult/causes.html [Accessed April 16, 2021] 

• Mayo Clinic staff. (n.d.) Obesity: Symptoms and Causes. Mayo Clinic. Available from: https://www.mayoclinic.org/diseases-conditions/obesity/symptoms-causes/syc-20375742#:~:text=Obesity%20is%20a%20complex%20disease,blood%20pressure%20and%20certain%20cancers. 

• Mayo Clinic staff. (n.d.) Obesity: Diagnosis and Treatment. Mayo Clinic. Available from: https://www.mayoclinic.org/diseases-conditions/obesity/diagnosis-treatment/drc-20375749 

• Moores, D. (2020) Obesity. Healthline. Available from: https://www.healthline.com/health/obesity#complications [Accessed April 16, 2021] 

• The World Health Organisation. (n.d.) Obesity. WHO Global. Available from: https://www.who.int/health-topics/obesity#tab=tab_1 [Accessed April 16, 2021] 

• Schousebou, JT., et al. (2018) Central Obesity and Visceral Adipose Tissue Are Not Associated With Incident Atherosclerotic Cardiovascular Disease Events in Older Men. J. Am. Heart. Assoc. 2018;7:e009172. https://doi.org/10.1161/JAHA.118.009172 

Global stats: The World Health Organisation. (2021) Obesity and overweight. WHO Fact sheets. Available from: https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight [Accessed June 15, 2021] 

Data: The Heart and Stroke Foundation South Africa. (2016) Cardiovascular Disease Statistics Reference Document. Available from: http://www.heartfoundation.co.za/wp-content/uploads/2017/10/CVD-Stats-Reference-Document-2016-FOR-MEDIA-1.pdf [Accessed April 16, 2021]

• Centers for Disease Control and Prevention. (2013) Genes and obesity. US CDC. Available from: https://www.cdc.gov/genomics/resources/diseases/obesity/obesedit.htm [Accessed April 16, 2021] 

• Centers for Disease Control and Prevention. (2020) Losing weight. US CDC. Available from: https://www.cdc.gov/healthyweight/losing_weight/index.html [Accessed April 16, 2021] 

• Chiolero, A., Faeh, D., Paccaud, F., Cornuz, J. (2008) Consequences of smoking for body weight, body fat distribution, and insulin resistance. Ame J. Clin. Nut. 87;4:801–809. DOI: https://doi.org/10.1093/ajcn/87.4.801 

• Traversy, G., & Chaput, J. P. (2015). Alcohol Consumption and Obesity: An Update. Current obesity reports, 4(1), 122–130. DOI: https://doi.org/10.1007/s13679-014-0129-4 

Shah, M. (2020) Is phentermine a good option for weight loss? Mayo Clinic. Available from: https://www.mayoclinic.org/healthy-lifestyle/weight-loss/expert-answers/phentermine/faq-20057940 

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