I used to be overweight for several years. Being overweight sucks. In addition to the usual aesthetic disadvantages, I was in for a lifetime of health problems associated with obesity. Losing weight is one the best things to happen in my life, and something for which I'll ever be grateful to God.
I lost weight by permanently changing my eating habits. I started eating a healthy, balanced diet (like a normal person) and started exercising regularly. I never did anything extreme, unnatural, unhealthy or unsustainable.
It really is that simple, but I'm saddened to see many people complicating things.
A simple sustainability test is asking yourself: "Can I reasonably do this for the rest of my life?". For example, it is nearly impossible to eat cucumber slices at lunchtime for the rest of your life. However, endeavouring to be a little bit more disciplined, and eating a balanced diet, is definitely possible.
It is not sustainable to starve, to over-exert yourself while exercising, or to go on abnormal diets. Being consistent over an extended period of time works far better than short, extreme bursts of the latest fad diet.
What comprises a healthy, balanced diet is dependent on a range of factors, and has to be custom designed taking into account an individual's lifestyle and energy needs.
A person cannot eat the diet of an Olympic swimmer in intensive training, and expect to lose weight. The same goes for the erratic eating habits of the average teenager.
Good health is only going to last as long as a healthy lifestyle is practised. Falling back into old, unhealthy habits will rapidly lead to weight gain and poor health.
I'm not overweight now, and have been this way for the past few years without any significant fluctuations in my weight. I still enjoy good food and make a small allowance for it. Staying healthy will require constant discipline.
Becoming overweight remains one of my greatest fears, but in the meantime, it is nice to fit into clothes designed for normal people, to not be judged negatively based on my appearance, and to be able look into the mirror, and smile.