The secret to losing weight
As a nation, we are getting fatter and fatter. It is now estimated that approximately 60% of the Australian adult population are overweight or obese; a figure which has more than doubled over the past 2 decades. Given the health complications associated with carrying excess body fat, these figures may sound bad from a public health perspective, but not so from a business point of view, as many overweight people are willing to fork over a considerable amount of money to anyone able to offer them a solution. In fact, the average Australian woman spends around $250 annually on weight loss – many doing so even if not overweight! 
Given that the population is certainly not getting any thinner, it would seem apparent that whatever it is that people are buying isn't working. One may therefore start suspecting that the key to successful weight loss must be some kind of well hidden secret, and consequently set out to find this secret, spending a lot of money in the process.
Fortunately for me, I happen to be among the few privileged people lucky enough to be aware of what this multi billion dollar industry secret is. Fortunately for you, I have decided to share it with you, but only if you promise not to tell anyone! (When I use this introduction in the seminars I often give, the entire room suddenly falls silent except for the sound of a few desperate people scrambling to get to their pens out in order to write down what the secret is.) Are you ready for it?
Adipose tissue (fat) is essentially our bodies' way of storing excess, unused chemical energy. Other than by surgical means, in order to get rid of it, we must force our body to break it down to use as a fuel source, by consuming less energy (kilojoules / Calories) than what we expend through physical activity. In other words, body fat regulation is a matter of energy in vs energy out. In layman's terms, if you want to lose weight you need to eat less and exercise more.
That's about all you need to know to lose weight, though doing so healthfully and doing so in a way in which it is likely to be habit forming (and therefore last long-term) is going to be advantageous. Most fad weight loss schemes and diets work of course, because ultimately, despite the very different claims they all make, they are all essentially low energy diets.
To give an example, a clinical trial published in the January 2005 issue of the Journal of the American Medical Association studied 4 of the most popular diets in the United States , by randomly assigning people to follow either the Atkins Diet, the Zone diet, the Weight Watchers diet and the Ornish diet.  After 1 year, all four groups resulted in approximately similar amounts of weight loss and improvements in their cholesterol, insulin and C-reactive protein levels. As it turns out, regardless of the fact that all four diet made very different claims about why they made you lose weight, ultimately they were all energy restricted diets.
Whether or not they are good for you and whether they are realistically sustainable in the long run however are the key aspects that a good weight loss program should provide. In regards to long term health, the best kind of generic dietary recommendation is set out by the NHMRC's ‘Dietary Guidelines' and illustrated by Nutrition Australia's ‘Healthy Eating Pyramid'. Whilst these recommendations are intended to maintain a healthy body weight, they are also designed to minimize the risk of other diet related diseases, including (but no limited to) cardiovascular disease and certain cancers.
When it comes to long-term sustainability, I think it's reasonable to suggest that restrictive dietary regimes significantly different to what existing habits are like, will not last very long. Making subtle improvements to ones own usual diet, identifying cues preceding poor food choices and learning how to plan ahead to overcome them would be far more effective for long term success. Unfortunately however this doesn't seem to be what the market wants, or at least not what they are willing to open their wallets for.
Healthy Weight Loss --> Healthy Life
I spent a considerable amount of time in 2006 writing a book called 'Healthy Weight Loss --> Healthy Life: The essential guide to long-term healthy weight loss for Australian adults'.The majority of the book focuses on how to make subtle, heathier alterations to existing dietary habits. You can download part 1 here, or click here for more details.
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