What is obesity?
Obesity is a serious medical condition associated with having an excess amount of body fat. Obesity can cause serious health complications such as metabolic syndrome, high blood pressure, heart disease, diabetes, high cholesterol, cancers and sleep disorders.1a
How is obesity caused?
Energy imbalances, some genetic or hormonal conditions, and certain medicines are known to cause overweight or obesity.1b
1. Energy imbalance.
The fundamental cause of obesity is an energy imbalance between calories consumed and calories used.2a
Energy is measured in calories. When you take in more calories than you use, this creates an energy imbalance causing your body to store fat. This means your energy IN (food/drinks) does not equal your energy OUT (exercise).1c,d
The amount of energy that your body gets from the food that you eat depends on:1f
- the TYPE of foods you eat
- how the food is PREPARED
- how LONG it has been since you last ate
2. Medical conditions that can cause obesity
The body produces hormones that help maintain energy balances in the body. Conditions that affect these hormones can cause obesity.1g These include:
Hypothyroidism. This condition is when a person has low levels of thyroid hormones. These low levels are associated with decreased metabolism and weight gain even when food intake is reduced. People with hypothyroidism also produce less body heat, have a lower body temperature and do not efficiently use stored fat for energy.1h
Cushing’s syndrome. People with this condition have high levels of a hormone called cortisol. High cortisol levels make the body feel like it is under chronic stress. As a result, these people have an increase in appetite and the body stores more fat.1i
Tumours. Some tumours near parts of the brain that control hunger can cause severe obesity.1j
3. Medicines that can cause obesity
There are also medicines that can cause weight gain that leads to overweight and obesity, such as antipsychotics, antidepressants, antiepileptic drugs, and medicines used for diabetes.1k
Talk to your doctor if you notice weight gain while you are using any one of these or other medicines. Do not stop taking the medicines without consulting your doctor first.1k
What other factors increase the risk of becoming obese?
Unhealthy lifestyle habits put people at higher risk of being overweight or obese. These include lack of physical activity, unhealthy eating patterns, not enough sleep and high amounts of stress.1l
Unhealthy environments. Factors such as easy access to unhealthy fast foods, limited access to safe areas to exercise and play and exposure to chemicals can increase the risk for overweight and obesity.1m
Age. The risk of unhealthy weight gain increases as you get older, however childhood obesity is also a serious problem.1n
Race and Sex. Overweight and obesity can differ between race and between males and females. The body stores fat differently in men compared to women. Women tend to store less unhealthy fat in the stomach area than men do; and women with polycystic ovary syndrome (a condition that reduces fertility) are at greater risk for obesity.1o,p
Genetics. Obesity can run in families – this means that genes associated with obesity/weight gain can be passed down in your DNA to your child. Eating too much or too little during pregnancy can affect how your child stores and uses fat later in life. Studies have also shown that obese fathers have DNA changes in their sperm that can be passed on to their children.1q
Why is obesity a worldwide problem?
Did you know?
Worldwide obesity has nearly tripled since 1975!2b
As of 2016; almost 40 % of adults are overweight and 13 % are obese.2c
Obesity kills more people than underweight.2c
Obesity is preventable.2d
Globally there has been:2e
- an increased intake of energy-dense foods that are high in fat and sugars.
- an increase in physical inactivity due to the inactive nature of many jobs (desk-bound), changing modes of transportation (less walking) and increasing urbanisation.
Signs and symptoms
The signs of obesity include a high body mass index (BMI) and an unhealthy body fat distribution.1r
BMI is a simple calculation that uses both weight and height to determine your weight category (see table below).2f
A person with a BMI greater than or equal to 30 is classified as obese.2g,3
Unhealthy fat distribution – obesity is not only about having a high BMI. A waist circumference over 89 cm for women or 102 cm for men - can help diagnose obesity.3b Having an increased waist circumference suggests that you have increased amounts of fat in your abdomen (stomach area). This is a sign of obesity and increases your chances for obesity-related complications.1s-u
What are the common consequences/complications of being obese?
Obesity may cause the following complications:1v
- metabolic syndrome
- high cholesterol
- cardiovascular diseases (heart disease and stroke)
- breathing problems (sleep apnoea, asthma)
- back pain
- Osteoarthritis (a major cause of knee replacement surgery in patients who are obese for a long time)
- incontinence (weak bladder)
- low self-esteem or depression
Almost half a million new cancer cases per year can be attributed to overweight and obesity!3c
Treatment depends on the cause and how severe the condition is. Treatments include lifestyle changes, such as healthy eating and increased physical activity (exercise). There are also weight-loss medicines that can be prescribed, and surgery may be a treatment option.1x,4a
How can overweight and obesity be reduced?
Following a healthy eating plan with fewer calories taken in is usually the first step in trying to treat overweight and obesity.4b When combined with healthy eating, regular physical activity will help you lose weight and stay at a healthy weight.4c
Ways in which you can change your lifestyle and decrease your risk of obesity:
Change to healthy eating patterns:1z,2h
- eat according to your daily calorie needs and not more!
- eat less saturated and trans fats
- avoid foods with added sugars
- increase consumption of fruit, vegetables, legumes, whole grains and nuts
Increase physical activity:1y
- exercise more
- reduce screen time
Get enough sleep:1aa
- lack of sleep can affect hormones that control hunger urges
- stress can affect the brain and trigger the production of cortisol, a hormone that controls our energy balances and hunger urges
Government policies such as ‘sugar-tax’ on sweetened beverages are a way to help people make healthier dietary choices.2i,5a
What is the big deal with soft drinks?
Sugary drinks have no nutritional value. The average 500 ml fizzy drink contains around 10 spoons of sugar!5b
Added sugar may be the unhealthiest ingredient in the modern diet6a
Alternatives to sugar
Sugar-free sweeteners, like xylitol, look and taste like sugar but have fewer calories and don’t raise blood sugar levels.6b
- Xylitol has a similar sweetness to sugar but contains 40 % fewer calories!6c
Xylitol is an example of a ‘sugar-alcohol’. A sugar alcohols chemical structure allows for stimulation of the taste receptors on the tongue which results in a sweet taste. Xylitol is an example of a naturally occurring sugar alcohol found in many fruits and vegetables. It is a common ingredient in sugar-free chewing gums, diabetes-friendly foods and is a weight-loss friendly sweetener.6d
For people with diabetes, obesity or other metabolic problems, xylitol is a useful alternative to sugar.6e
*Note: Despite their name, sugar alcohols aren't alcoholic because they don't contain ethanol, which is found in alcoholic beverages.6f
For more information click on this link : https://www.adcock.co.za/ProdFoodNutrition
- National Institutes for Health (NIH). Overweight and Obesity. Available at: https://www.nhlbi.nih.gov/health-topics/overweight-and-obesity Last accessed September 2020.
- World Health Organisation (WHO). Obesity and overweight. Key Facts [April 1, 2020]. Available at: https://www.who.int/en/news-room/fact-sheets/detail/obesity-and-overweight Last accessed September 2020.
- Herbst MC. Fact Sheet on Obesity and Cancer. Cancer Association of South Africa (CANSA) [January 2019].
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). National Institutes for Health (NIH). Treatment for Overweight & Obesity [February 2018]. Available at: https://www.niddk.nih.gov/health-information/weight-management/adult-overweight-obesity/treatment Last accessed September 2020.
- National Department of Health. World Obesity Day 2016. Available at: https://www.gov.za/sites/default/files/gcis_document/201608/policy-paper-and-proposal-taxation-sugar-sweetened-beverages.pdf
- Gunnars K. Xylitol: Everything You Need to Know. Healthline. [October 4, 2018]. Available at: https://www.healthline.com/nutrition/xylitol-101#low-glycemic-index Last accessed September 2020.