I'm a little bit chubby. Sometimes I struggle to close the button at the top of my jeans and more often than not, I happily indulge in that extra helping of pudding. But that does not mean that I'm in danger of becoming obese… or does it?

In a world polarised by skeletal models and an increasingly obese population, it is difficult to figure out just how fat is too fat.

As it turns out, I'm okay. With a body mass index (BMI) of 22.5 I fall comfortably (well, sort of) into the healthy weight category. I would need to put on another 20 kilos before I am classified as obese, but only another seven kilos before I drift into the overweight category.

Although generally regarded as a good method for figuring out whether or not your weight is healthy, BMI can be deceptive in the cases of pregnant women or serious athletes (because muscle weighs more than fat).

Luckily, figuring out your BMI doesn't take any fancy equipment or uncomfortable trips to the doctor. All it takes is a nifty little maths equation.

Take your height in meters (eg. 1.63) and square it (2.6569). Take your weight in kilos (eg. 60 kilos) and divide it by your height squared (2.6569) and the answer (in this case 22.58) is your BMI.

So, what does it mean?

• BMI under 18.5 — underweight


• BMI between 18.5 and 24.9 — healthy weight


• BMI between 25 and 29.9 — overweight


• BMI over 30 — obese


• BMI over 40 — morbidly obese

Another method of establishing whether you are in danger of developing the diseases associated with obesity is by measuring your waist or your waist-to-hip ratio. Central obesity (predominant in males) occurs when there is too much fat around your organs. Generally people with 'apple' rather than 'pear' shapes are more susceptible to this type of obesity.

To figure out whether you are an apple or a pear, you need to measure you waist/hip ratio. You can do this by taking your waist measurement and then dividing it by your hip measurement. If your waist-to-hip ratio exceeds 1.0 (men) or 0.85 (women) it indicates the risk of obesity.

A killer condition

So, what's the big deal? Not everyone can (or wants) to be a skinny model. True, but obesity has far more serious ramifications than not being able to fit into your favourite pair of jeans. In fact, it could just kill you.

According to a 2005 World Health Organisation report, there are at least 400 million adults and 20 million children suffering from obesity around the world. In South Africa, it is estimated that 6.7 percent of males and a shocking 35.2 percent of females are obese.

A 2006 Medical Research Council report claimed that 29 percent of South African men and 56 percent of women are classified as either overweight or obese.

Obesity can chop up to nine years off your life and is associated with a battery of serious medical conditions. Most fatally, obesity can cause diseases of the heart and circulatory system including coronary heart disease, strokes and congestive heart failure.

If you are obese, you are also three times more likely to develop hypertension (high blood pressure), 40 times more likely to develop type two diabetes, and four times more likely to suffer from gallbladder diseases. Osteoarthritis and gout are also commonly found in overweight and obese individuals.

While the risk posed by these conditions increases as you put on weight, health problems begin when someone is only very slightly overweight. So, if you fall in that 25 to 30 bracket, now is the time to start taking control of your health.

What causes obesity?

Although the 'cause' of obesity is rather simple — consuming more calories than you burn — there are a number of factors which increase the likelihood of the condition and explain why obesity is becoming more and more prevalent.

• Genetics — you are more likely to develop obesity if one or both of your parents are obese. Genetics affect the hormones involved in fat regulation. Once an obesity-prone individual actually becomes obese, it is nearly impossible for them to return to a healthy weight.
• Metabolism — women are more likely than men to become obese because they tend to have slower metabolisms.
• Medication — certain medications are associated with weight gain. These include certain anti-depressants, anti-convulsants, corticosteroids and oral contraceptives.
• Medical conditions — various medical conditions, such as hypothyroidism, insulin resistance, polycystic ovary syndrome and Cushing's syndrome, are associated with abnormal weight gain.
• Childhood weight — being mildly overweight during older childhood and you teenage years makes you statistically more likely to develop obesity as an adult.
• Lack of sleep — you are more likely to be overweight if you don't get enough sleep (at least six hours) on a regular basis. A lack of sleep results in high levels of a hormone called ghrelin (which causes hunger) and low levels of leptin (which curbs hunger).
• Sedentary lifestyle — a sedentary lifestyle, along with a fast-food-saturated diet, is largely to blame for the increase in obesity. If your job involves sitting at a desk for most of the day, you are more likely to become overweight.

Fat attack

Obesity needs to be treated as a chronic condition. There are no quick fixes and because the condition has high relapse rates, overcoming it will be an ongoing life-long process. More than 95 percent of those who lose weight regain it within five years.

It is also important to note that, while being even slightly overweight increases your health risks, modest weight loss (five to 10 percent of initial weight) can be beneficial.

Tackling obesity can be a long and arduous task — the instruction to eat less (or the correct foods) and exercise more is not particularly helpful. Here are some useful tips for making sure that your fat attack works.

Have a plan
A vague resolution that you should probably lose some weight is not a plan. Your plan needs to be specific, realistic and full of details. Consider every aspect of your life — your eating habits, your exercise routine (or lack thereof), your attitude, your emotional responses and your attitude to life.

Write everything down, and then write down a specific plan (including a timeline and concrete suggestions). Make sure that your expectations are realistic. If not, you will inevitably become disheartened when you fail. Once you have a plan, stick to it! No excuses…

Change your patterns
It is easy to use food as a reward when things are going well and as a comforter when you are feeling down. Try to change these patterns so that you are only eating when and because you are hungry. Replace food with other treats and coping mechanisms such as a good book, a chat with a friend, a pampering session or a yoga class.

You need to change not only why you eat, but also how you eat. Practice saying no to unhealthy foods — the more you say it, the easier it will become. Try having smaller portions and don't have second helpings, even when you think you are still hungry.

Keep a food diary
Most of the time, we don't realise just how much we are eating. You forget about that little snack before lunch and the chocolate you had on your way home from gym doesn't really count. Wrong! When it comes to combating obesity, every calorie counts. You need to balance your calorie intake with your energy expenditure.

Keep a food diary and write down not only everything that you eat, but also the number of calories. Most adults need between 1200 and 2800 calories a day depending on your body size and activity level. If you are able to record the calories you burn during exercise, include this in the diary too. It is a good idea to take note and congratulate yourself when you are doing well.

Because obesity is linked to various health concerns, it is a good idea to also keep track of your blood pressure, cholesterol and overall fitness.

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