Maintaining a healthy weight is one of the best things you can do to protect your overall health. Being overweight or obese increases your risk for having a heart attack or stroke as well as numerous other health problems including high blood pressure, certain cancers, diabetes, gallstones, sleep apnoea and degenerative joint disease.

Being overweight is a condition of excess fat on the body to the extent that it may have a negative effect on your health. Becoming overweight is the eventual result of habitually taking in more energy from foods compared to the amount of energy burned by the body as part of normal bodily functions and during physical activity. Even a small but consistent energy surplus can cause gradual weight gain.

Becoming overweight is typically the result of poor eating habits and low activity levels. These habits are in turn influenced by individual behaviour, mood, background and the surrounding environment. In fewer cases, obesity can be caused by factors outside a person’s direct control, including:

  • Family history and genetic causes of obesity
  • Certain medical conditions, medications and changes in hormone levels
  • The more pregnancies a woman has had, the more likely she is to be overweight or obese

How many South Africans are overweight?

  • 2 out of 3 women and just under one third of men in South Africa are overweight or obese
  • Almost 1 in 4 children aged 2-14 years are overweight or obese in South Africa. These children have an increased risk of developing chronic diseases such as diabetes and cardiovascular disease earlier in life and are more likely to remain obese throughout their adult life.

Advice for weight management

Losing weight is not easy, not to mention trying to lose a large amount of weight, which can seem daunting and near-impossible. Unfortunately, a large percentage of people who lose weight successfully, regain some or all of the weight again afterwards too.

This does not mean that successful weight loss and keeping the weight off is impossible. However, it is most likely when using a comprehensive approach that includes changing eating habits, increasing activity levels, and making changes to lifestyle habits that can be continued long term. Research shows that joining a weight loss programme for 6 months and receiving ongoing support thereafter is particularly successful. If this is not possible, regular follow-up sessions with a registered dietitian and exercise professional can be of great value. These professionals can help to set realistic personal targets, assist in selecting the best approach, and provide ongoing support and advice.

Fad or crash diets are a popular way to reduce food intake to bring about weight loss. Most often these diets require radical changes to eating patterns which are not healthy, practical, or affordable in the long-term, which means they become unsustainable. Furthermore, fad diets that result in rapid weight loss often cause initial body water and muscle loss, which are counterproductive. Such weight loss diets only provide temporary benefit until the person returns to their previous routine diet and regain the weight.

A healthy eating pattern that suits the individual’s circumstances is the best method to control how much energy from food and drinks is consumed to assist in losing weight. Once a weight loss goal has been reached, the next goal is to avoid regaining lost weight and making lifestyle changes permanent. Successful weight maintenance is more likely when there is regular support and contact with a programme, healthcare professional, or peers. Other factors that make success more likely includes continued regular physical activity, monitoring weight regularly, and creating new daily habits that suit personal preferences.

Learn more about the components of successful weight loss below.

Body Mass Index

Body Mass Index (BMI) is commonly used to classify weight in relation to height and a high BMI means someone is too heavy for their height. BMI may not be accurate in people who are very muscular like athletes or rugby players. Even people with a normal BMI can still have excess weight around their stomach, therefore BMI is best used in combination with waist circumference. BMI is only suitable for adults because children need to have a BMI score calculated specific to their age. Ask a health care professional to do this.


Calculate BMI by dividing weight in kilograms by height in centimetres TWICE.

For example:               90 kg / 180 cm = 50.            50 / 180cm = 27.8

Waist circumference

The distribution of excess weight around the body matters. That’s because the type of fat that accumulates around the stomach area, called abdominal fat, is more dangerous than subcutaneous fat – the fat underneath the skin spread across the rest of the body. Visceral fat, also commonly called visceral fat, is more likely to cause diabetes, abnormal blood cholesterol, high blood pressure, and heart disease. Waist circumference measures abdominal fatness by a measurement in centimeters around the waist, at the level of the belly button.

If someone is overweight and they have other risk factors for cardiovascular disease such as high blood pressure, cholesterol or glucose, then even 2 – 5 kg of weight loss can produce significant health benefits, with greater weight loss providing even greater benefits. Weight loss is likely to improve:

  • Triglycerides (levels of fat in the blood)
  • Blood pressure
  • LDL- and HDL–cholesterol
  • Fasting blood glucose and HbA1c in people with diabetes
  • Risk of developing type 2 diabetes
  • Risk of heart disease and strokes

To achieve weight loss, a reduction in energy intake from foods of approximately 2 000KJ (500 calories) less per day than usual is needed. In doing so, the body starts to use some of the stored fat reserves for energy.  There is not one specific diet that is best to achieve weight loss, rather it is more important to find a new eating pattern that suites the individual and that can be sustained long-term.

A variety of dietary approaches can be used to effectively lose weight, as long as the amount of energy from food and drinks is reduced in doing so: 

  • Mediterranean-style diet
  • Higher protein diets
  • Low-carbohydrate diets
  • Low-fat diets
  • Low kilojoule diets
  • Low-fat vegan style diets
  • Lower fat and high dairy diets
  • Diets than include meal replacements or structured meal plans
  • Commercial weight loss programmes that use one of these approaches

The key therefore lies in finding a dietary approach that suites the person’s lifestyle and taste preferences. It is also important to consider any existing medical conditions when deciding on a dietary plan. For detailed and personalised nutritional support and meal plans, contact a registered dietitian near you.

General nutrition weight loss tips

Eating to lose weight is not only about eating less energy to start burning fat. Different foods can increase or decrease the risk for disease such as high blood pressure, diabetes and heart disease. Read more about the foods that form part of a healthy diet here.

In addition to making healthy food choices, these tips can be useful to lose weight, irrespective of the dietary strategy followed:

  • Create a regular eating routine on a daily basis.
  • Reduce portion sizes
  • Eat slowly and mindfully
  • Limit the intake of drinks that contain unnecessary energy, such as sugary drinks and alcoholic beverages
  • Plan ahead for meals, particularly what to eat at work or school
  • Drink plenty of clean fresh water
  • Increase the amount of non-starchy veggies as part of meals or snacks
  • Choose higher fibre or wholegrain foods instead of refined starches, to stay fuller for longer
  • Limit foods that contain added sugar or fats
  • Get support and encouragement from friends and family

Modern lifestyles include motorized transport, less physical activity at work, more time spent sitting in front of a TV or computer, and less active leisure time. Most people are leading much less active lives compared to even 10 or 20 years ago. Exercise is often seen as a sure way to lose weight. Yet, to increase exercise requires more fuel, which stimulates weight loss but also increases appetite. In a modern environment where food is plentiful, it is easy to compensate for the fuel expended in exercise by increasing food intake. Therefore, exercise alone is seldom a recipe for successful weight control.

Gradual and sustained weight loss is best achieved by combining a healthy eating pattern with regular physical activity. Individuals should aim for at least 150 minutes a week of moderate intensity physical activity – any activities that increases heart rate and breathing rate. Individuals who exercise even more or at higher intensity achieve better results and are more successful at maintaining weight loss. Exercise should include some activity that strengthens muscles and maintains muscle mass such as weight training, body-weight exercises, heavy gardening or yoga. Weight loss that occurs too rapidly may result in a loss of muscle tissue, which can lead to a plateau in weight loss thereafter or weight regain.

If you are not currently exercising or very unfit then it is important to start slow and build up gradually as your fitness levels increase. An exercise professional like a biokineticist or personal trainer can develop a personalised plan and provide ongoing supervision. Read more about exercise here.

Weight loss is not only about the foods eaten and amount of exercise, but also about why people behave in a certain way. Most regular habits, good or bad, are established over time by repeating them many times. Breaking bad habits and creating new, better habits in their place can be particularly difficult. It is important to consider the obstacles to change, readiness to change, motivation, and the external factors that influence eating and exercise habits. Behaviour therapy includes strategies to self-monitor progress, to be more mindful about what and how to eat, and changing thought patterns. It also uses strategies like goal setting, problem-solving, stimulus control, and planning ahead to avoid possible obstacles. In addition to nutrition and exercise professionals, a psychologist or counsellor can help to implement behaviour strategies to effectively lose weight.

Lifestyle changes including changes in eating, exercise and behaviour are the first steps to lose weight successfully. In some cases, weight loss medications can help in addition to lifestyle changes. A medical doctor can prescribe suitable medication when indicated and safe for that person. In people who have severe obesity and when lifestyle changes have been unsuccessful, weight loss surgery can be considered. Weight loss surgery does have risks and may not be financially feasible but should be discussed with a medical doctor.