Let’s begin by exploring the definition of obesity:
‘abnormal or excessive fat accumulation that presents a risk to health. A crude measure of obesity is the body mass index (BMI), which is a person’s weight (in kilograms) divided by the square of their height (in metres). A person with a BMI of 30 or more is generally considered obese. A person with a BMI of 25 or more is considered overweight’. (World Health Organisation)
The World Health Organisation acknowledges that this definition is crude, since ‘weight’ can be made up of fat, muscle and bone density, in differing proportions. Someone who is muscular with a high bone density could have a BMI that exceeds 25 but they are likely to be healthier than someone who simply carries abundant excess fat.
I would go a step further and say that not all fat is made equal. If the excess fat you are carrying is due to consuming more calories than you are burning of whole-foods rich in nutrients (think plump and rosy-cheeked like one of Thomas Hardy’s dairy maids), then you are doing better than someone who is carrying excess fat made from highly acidic, processed food (think Homer Simpson). I call this latter type ‘toxic’ fat – it is dangerous and more likely to trigger cancers, diabetes and heart disease. Carrying this type of fat means you are likely on a journey towards obesity and morbid obesity. If you think about it, how many people do you know who have become obese due to a calorie-excess in the form of fresh eggs, meat, olive oil, wholegrains, vegetables, fish and organic dairy products? Not many – there’s normally a great deal of processed food to account for their weight gain.
Obesity, over -time (particularly if you are carrying lots of ‘toxic’ fat), becomes more than just an issue of excess. Long-term obesity fundamentally derails your body and plays havoc with your endocrine system, i.e. the hormonal and chemical signalling in your body. The chemicals that tell us we are full stop working; we confuse thirst for hunger, our thyroid slows, our pancreas becomes inefficient at producing insulin, our fertility declines due to excessive insulin and cortisol. Obesity, if left untreated, mutates from a ‘fat’ problem to a chemical problem.
Overweight also has a powerful psychological thread. Children and adults often over-eat because they are unhappy. This may be followed by a period of extreme dieting and excessive exercise. Then an obese phase might occur again because they have become so hungry. This cycle is destructive, to the point where people are totally lost as to what to put in their shopping trolley and don’t even know whether they are hungry or not. They have lost their ability to eat instinctively which is one of the saddest conditions of humanity.
It’s crucial to have a global metric to assess whether someone is a healthy weight or not. But obesity is a complex, multi-dimensional problem and simply can’t be flattened into a two-dimensional summary like ‘their BMI is too high’ or ‘they eat too much’. In many cases obesity involves significant unpicking and therapeutic work if someone is going to really conquer it. In addition to gaining metric intelligence, any weight loss expert or health professional needs to be asking their weight loss clients these important questions, at the very least:
• How long you been overweight?
• What type of food do you eat?
• Do you have any hormonal problems?
• How do you feel in yourself?
• What is your relationship with food like?
Next week we will look at where obesity is most prevalent, both across the world and in the UK, and why that might be.
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