Updated: Sep 23, 2020
Bear with me. I don’t want to weigh in on any issues, feminist or otherwise! But fat is an issue. This has nothing to do with society’s pressures to be slim and gorgeous, nor your right to be fantastic at whatever size you choose. This is purely to do with science and your health.
There is no doubt about it, we are becoming larger. The Australian National Health Survey 2017-18 reported that since 2014-15, the proportion of adults aged 18 years and over who were overweight or obese increased from 63.4% to 67.0%. This change was driven by the increase in the proportion of adults categorised as obese, which increased from 27.9% to 31.3%.
Does it matter? Well, yes it does. The epidemic of obesity carries with it a whole raft of health problems. Being overweight or obese is seen as a major risk factor for type II diabetes, cardiovascular disease, kidney disease, cancer, neurological, musculoskeletal and respiratory conditions. And, once any kind of disability sets in, physical activity becomes harder, life becomes more sedentary and of course this exacerbates the problem.
Why does extra weight cause health issues? The answers are various. Some are more obvious than others. It is easy to see that excess weight can put pressure on joints and worsen arthritis for example. Those needing a knee replacement are often asked to attempt to lose some weight to improve their outcomes. The more hidden issues however are to do with the behaviour of the adipocytes, or fat cells.
‘Normal’ fat cells are simply filled with stores of fat ready for use in times of need such as when food is scarce, you are ill and disinclined to eat, or when exercising long and hard and in need of extra energy to fuel the exercise. When these cells become ‘obese’ or ultra filled with fat they actually start to send out signals to the rest of the body via chemicals called adipokines. This is similar to the signalling that occurs when the body’s immune system is activated by a foreign threat (such as a virus or bacteria). Immune cells are attracted to the area to ’fight’ this perceived threat. The ‘threat’ cannot be rectified because the overfilled fat cells are still there, so the inflammatory response becomes chronic. Ultimately this leads to insulin resistance.
Insulin resistance means that the body no longer registers the signal of insulin hormone to regulate sugar levels in the blood stream. If this is not addressed it can develop into type II diabetes. Additionally, unregulated sugar can join onto haemoglobin proteins to form toxic molecules called glycated haemoglobin. This leads to more free radicals in the blood cells and causes them to aggregate together, impairing blood flow.
Another mechanism of action of glycated haemoglobin is to cause build up of plaque in arteries. Add to this its tendency to bind to nitric oxide (which would normally be a powerful vasodilator, allowing blood vessels to dilate and increase ease of blood flow) and the possibility of heart disease occurring become clear.
Is all fat dangerous? It seems that fat around the organs such as the heart, kidney and particularly the liver is more of a concern that fat evenly distributed around the body. Thus someone with a large waist circumference but relatively skinny limbs is at greater risk than someone who carries their fat evenly. Men are more likely to carry belly fat then women who have a tendency to put weight on their hips and legs as well as the belly.
Measuring your waist circumference is probably a good way to assess whether you should consider doing something about your weight. It is a more accurate marker of problematic fat than body mass index, or overall body mass. Obviously your ethnic background and height can make a difference to your overall body shape. The World Health Organisation has developed cut off points as a guideline to a ‘safer’ or ‘less risky’ waist measurement.
These are summarised below.
Source: Adapted from Zimmet and Alberti (2006)
Australia, like many countries around the world, both developed and developing, has a rapidly growing diabetes type II epidemic which is closely related to the fact that the population as a whole is not maintaining a healthy body weight and shape. Added to this are the many complications of diabetes from nerve damage, blindness, gangrene and kidney disease to increased risk of cancer, stroke and cardiovascular disease. It’s not a pretty picture, nor an easy problem to solve.
Ultimately, our less active modern lifestyles and access to seductive fast food and processed foods has led to this situation but we need to address it on both a societal level and a personal one. Taking steps to be more active every day and to eat homemade, fresh foods is a great first step towards influencing your entire household to maintain a healthy weight and to reap the health rewards.