There are some battles you are destined to lose and one of those is a fight with nature!
There is an old adage known to sailors that when the wind rises the nervous sailor heads for port, the foolish sailor battles on while the wise sailor trims his sails. The wise sailor knows that if you understand what's happening, chart a sensible course to your destination, know your vessel and how to handle her you can use that rising wind to your advantage.
But if you fight it you will lose and if you return to port you have simply failed.
The problem with most modern approaches to weight loss, getting fit and handling stress and anxiety is that they set out to fight nature.
Dieting for weight loss
Contemporary diet approaches are destined to fail for so many reasons; both physiological and psychological.
Eating and satisfying your appetite are fundamental drivers of behaviour so resisting the temptation to eat is very hard. Our social relationships are closely linked to sharing food, many foods, particularly those with high sugar content are effectively addictive and we are constantly faced by adverts and even worse, television cookery programmes.
Giving something up that you enjoy results in your constantly thinking about it, a bit like a drug addict having their next fix constantly dangled in front of them. This is made worse by the idea that you only have to hold out a little longer and you can return to your old ways. You're faced with a constant battle with temptation - it's not fun!
At the physiological level, dieting raises cortisol levels which actually predisposes you to lay down more fat. You will almost certainly lose muscle mass, particularly if you follow a rapid weight loss diet. This will reduce testosterone levels affecting the body's ability to repair itself. Reduced testosterone will also affect your libido - both male and female.
Rapid Weight Loss Diets
Because dieting is so unpleasant, rapid weight loss diets are seen as attractive but their success is illusory. They achieve their effect by forcing your body to use its glycogen stores which are primarily designed for fight or flight situations. You have about a pound of glycogen stored which will yield around 2000 calories. It is stored with around 5 times its weight of water so when you burn off the glycogen you also lose the water.
Since the body desperately wants to restore the glycogen it will replace it s soon as there are some spare calories. Unfortunately, this means it will also add back the water.
The further bad news is that it will have a wide range of additional effects on both body and mind; it raises stress levels, affects a wide range of hormones and reduces the amount of "passive" energy you burn.
Long term effects
The most profound effect of dieting is that your body will reset its "weight set point". Your body knows how much fat it should store to see it through the normal ups and downs of life. To ensure it has sufficient it has a "weight set point"; fall below that and your hormones will drive you to add more weight, exceed it and they will switch off that drive.
But your body is very clever; that "set point" is not unchanging. It varies this in response to a variety of factors so, for example, pregnant women will lay down more fat in preparation for rearing the newborn infant. Other life-changing events will also move the setpoint, moving house changing jobs and other stressful events can also change it.
When you diet the body recognises this as a famine. When food becomes available again it will adjust the body's weight set point upwards in order that the hormones that stimulate and suppress appetite are regulated to ensure you lay down more fat in readiness for the next famine.
This tends to happen with all "diets" but it's particularly profound in the case of the popular "rapid weight loss" diets since these represent a profound shock to the system.