Health Guide - Overweight
and Obesity

September 05, 2017

They are associated with mental health problems, reduced quality of life and are major risk factors for many chronic diseases, including diabetes, cardiovascular disease and cancer. In this guide, we explore the main causes and associated risks of obesity and examine how weight can be controlled.

According to the World Health Organisation (WHO), globally there are around 2 billion adults overweight, of those 768 million are affected by obesity. If current trends continue it is estimated that 2.7 billion adults will be overweight and 1.1 billion considered obese by 2025.

Body mass index (BMI), a simple index of weight-for-height is commonly used to classify overweight and obesity. BMI is defined as a person’s weight (in kilograms) divided by the square of his or her height (in metres).

BMI = weight in kg/height in m2

Although BMI provides a useful measure of overweight and obesity, it should only be considered a guide because it may not correspond to the same degree of overweight in each person.

The distribution of body fat is also a crucial determinant of some obesity-associated health risks. People who carry most of their weight around the waist, may be at greater risk of heart disease and type 2 diabetes than people who carry weight on their hips and thighs.

Waist circumference is considered a reasonable indicator of excess weight. Women with a waist greater than 35 inches or men with a waist greater than 40 inches are at increased risk of associated health issues.

For adults, WHO defines overweight and obesity as follows:

Overweight is a BMI greater than or equal to 25; and obesity is a BMI greater than or equal to 30.

Overweight and obesity are a major risk factor for many noncommunicable diseases and health problems such as:

  • Cardiovascular diseases
  • Type 2 diabetes
  • Musculoskeletal disorders (especially osteoarthritis)
  • Some cancers (including endometrial, breast, ovarian, prostate, liver, kidney, and colon)
  • High blood pressure
  • High triglycerides and low high-density lipoprotein (HDL) cholesterol
  • Breathing disorders

Overweight and obesity may also have a detrimental impact on overall quality of life. As weight increases people may find they are no longer able to participate in activities they enjoy, leading to self-esteem and other mental health problems.

The main cause of overweight and obesity is an energy imbalance between calories consumed and calories expended, through exercise and normal daily activities. Excess calories are stored as fat by the body.

In general, overweight and obesity will occur due to:

A diet that's high in calories, excessive portions and lacking in fruits and vegetables, will inevitably contribute to weight gain.

The average physically active man needs about 2,500 calories a day to maintain a healthy weight, and the average physically active woman needs about 2,000 calories a day.

Obesity develops gradually over time, because of poor diet and lifestyle choices, such as:

  • consuming a high proportion of processed or fast food
  • excessive alcohol consumption
  • dining out a lot
  • excessive portion sizes
  • drinking a high proportion of sugary drinks
  • comfort eating to alleviate low self-esteem or depressive episodes

Unhealthy eating habits tend to run in families. Children may learn bad eating habits from their parents when  young and continue them into adulthood.

If you're not very active, you don't burn as many calories. With a sedentary lifestyle, you can easily take in more calories every day than you use through exercise and normal daily activities.

It is recommended that adults do at least 150 minutes of moderate-intensity aerobic activity, such as cycling or fast walking, every week.

Breaking this down to 30 minutes a day for five days a week, should be manageable even within busy daily schedules.

Your genes may affect the amount of body fat you store, and where that fat is distributed. Genetics may also play a role in how efficiently your body converts food into energy and how your body burns calories during exercise.

Although for some people genetic traits may make losing weight more difficult, it certainly doesn't make it impossible.

In some cases, medical conditions may contribute to weight gain. These include:

  • Hypothyroidism – where the thyroid gland doesn't produce enough hormone
  • Cushing's syndrome – a rare disorder that causes the over-production of steroid hormones
  • Prader-Willi syndrome – a rare genetic disorder that causes an inability to feel full
  • Arthritis – decreased activity from arthritis may result in weight gain

When diagnosed and treated, conditions such as these should pose less of a barrier to weight loss.

Obesity can run in families. If one or both parents are obese, a child’s risk of being obese is increased. This can have a genetic cause or may be due to the fact that family members have similar eating and activity habits.
Weight gain can sometimes be a side effect of stopping smoking. However, with calorie control and physical activity, this can be avoided.

Stopping smoking is always the correct choice.
Not getting enough sleep or getting too much sleep can cause changes in hormones that increase appetite.

During pregnancy, a woman's weight necessarily increases. Some women find this weight difficult to lose after the baby is born. This weight gain may contribute to the development of obesity in women.

Even if you have one or more of these risk factors, it doesn't mean that you're destined to become obese. You can counteract most risk factors through diet, physical activity and behaviour changes.

Weighing yourself regularly is a great way to track progress if you are trying to lose weight, and to monitor any weight gain if you are trying to maintain your desired weight.

Aim to weigh yourself once a week:

  • At the same time of day
  • On the same day each week
  • Wearing similar clothing each time
  • Always using the same weighing scale

Remember to place weighing scales on an absolutely flat surface.  An uneven floor can lead to inaccurate measurement.

Overweight and obesity, are largely preventable. Whether you're at risk of becoming obese, currently overweight or at a healthy weight, you can take steps to prevent unhealthy weight gain and related health problems.

Aim to be active for at least 30 minutes every day with these practical tips:

  • Try cycling, jogging or walking part of the journey to work
  • Always take the stairs or walk up the escalator
  • Get active at lunchtime – try walking or jogging with a colleague
  • Allocate some time every evening for exercise – it’s good for body and mind

A healthy balanced diet is essential for overall health.  A main meal should consist of three-quarters vegetables, beans or grains and one-quarter meat, fish or protein, try to choose water over other beverages.

Reduce salt intake and try to avoid too many sugar rich and processed foods.

Most fruit and vegetables contain necessary nutrients, are low in calories and high in fibre, ideal for maintaining or attaining a healthy weight. Aim to eat at least 5 portions of fruit and vegetables per day with these practical tips:

  • Add bananas or berries to breakfast cereal
  • Cook more meals from scratch
  • Blend vegetables and beans to make soups and sauces
  • Keep a well-stocked and easily accessible fruit bowl
Keep a food log, to help identify situations that cause over eating. Write down what you eat, how much you eat, when you eat and how you are feeling.
Over time any unhealthy eating patterns will emerge, knowing when these situations occur will help to avoid them.
People who weigh themselves at least once a week are more successful at keeping off excess weight.
Regular weight monitoring can identify which weight control strategies are working and can help identify if weight is slowly increasing.

Stay on target and follow a healthy eating plan even on weekends and holidays for a successful weight control plan.

It is ok to have an occasional treat, food is for pleasure as well as fuel, but remain on a healthy eating and weight control plan. This means less calories consumed and more calories expended.

If you are trying to loose weight a food diary helps you keep track of what you eat each day, assisting you with making healthy changes to your diet.
Keep your diary with you all day. Write down everything you eat and drink.
Don’t rely on your memory at the end of the day. Writing down what you eat, as you eat, will ensure that your diary is accurate.
Keep a record of how your food has been prepared. Be sure to include details such as dressings or sauces and whether food was fried or grilled.
Keep a record of portion sizes, even if it's just an estimate.

Overweight and obesity in children is one of the most serious global public health challenges, and is associated with a higher chance of premature death and disability in adulthood. In addition to increased future risks, carrying extra body weight can put children at increased risk for developing serious health problems, including diabetes, heart disease, and asthma.

Obese children may also experience breathing difficulties, increased risk of fractures, hypertension, early markers of cardiovascular disease, insulin resistance and psychological effects. Recognising and treating weight problems and obesity in children, may reduce the risk of developing serious medical conditions as they get older.

Childhood obesity also takes an emotional toll. It is important for children to develop high self-esteem, feeling good about themselves can affect their mental health and behaviour. In many cases self-esteem can be closely linked to body image and weight. Overweight and obese children often have trouble keeping up with other children and joining in sports and activities. Other children may tease and exclude them, leading to low self-esteem and negative body image.

Addressing weight problems in children requires a combination of physical activity and healthy nutrition. Most cases of childhood obesity are caused by eating too much and exercising too little. Children need enough food to support healthy growth and development. But when they take in more calories than they burn throughout the day, the result is weight gain.

The number of calories a child should eat each day will depend on their age and height. If you have concerns about your child’s weight, talk to your doctor who will advise you on recommended daily calorie limits.

  • Get the whole family involved
  • Encourage healthy eating habits
  • Lead by example
  • Limit snacks
  • Monitor portion sizes
  • Reduce screen time
  • Get your child moving – increase daily exercise and activity

Children over the age of five should ideally get at least 60 minutes of exercise a day, such as running or playing football. Sedentary activities, such as watching television and playing computer games, should be restricted.

As a parent, ensuring your child consumes a healthy, balanced diet and gets sufficient daily exercise, may mean that discussions about weight are not required.

However, if a child is experiencing overweight or obesity, the issue must be addressed and dealt with sensitively to avoid causing upset or creating other emotional issues for the child.

  • Talk about weight positively as a health matter
  • Don’t talk about losing weight or dieting
  • Focus on the habits that can be changed
  • Encourage childhood self-esteem
  • Make changes together as a family
  • Let your child know that you love them and that all you want to do is help them be healthy and happy.
Obesity is reaching pandemic proportions across much of the world and its consequences are set to impose unprecedented health burdens on global society.

If you are unsure whether your current weight is at a healthy level, check your BMI on our BMI Calculator, the results will guide you towards the ideal weight for you and your children and the steps you can take to achieve a healthy lifestyle. If your BMI falls within the overweight or obese categories, talk to your doctor about the best weight-loss approach for you. Opt for more sustainable lifestyle changes to your diet and physical activity levels, which will result in long-term healthy eating habits and a greater ability to control weight.

“One often overlooked culprit  of weight gain, when considering a healthy and low calorie food plan, is sugary drinks.

This includes all sodas , commercially produced ice tea and fruit juices. Fruit juices might seem healthy at first sight , but can be very high in sugar.

One solution is to drink more plain water and make your own fruit juices : use a blender instead of a juicer , as this will preserve the fruits skin which acts as a wonderful source of fibre that will slow down sugar absorption in the bowel, and be sure to add plenty of water.” Dr Ulrike Sucher, Medical Director, Allianz Worldwide Care.