Six years ago, Alanna Collen began talking to the world’s leading weight scientists in pursuit of her belief that however much you dieted your body would always override your willpower. The evidence was everywhere, not least in the fact that after 70 or so years of bestselling diet programmes few people managed to keep the weight they had lost off. Historically, it was also obvious that people were far slimmer and healthier in the past, and not because there was less food.

And then the research results began to come in which backed up Alanna’s scientific hunches, pointing to the existence of an automatic drive to make us over-weight. But why? What is this drive? Where does it come from?

Alanna has pieced together a truly revolutionary answer: the hypothalamus, the tiny brain structure that acts as the control centre for so many of our functions, has been damaged. This is crucial as the hypothalamus not only regulates your sleep but keeps your body temperature constant and also controls levels of thirst, sexual function and more.

Crucially, it’s the hypothalamus that decides what weight you should be, and it does everything in its power to divert calories to your fat stores, or to your muscles, in pursuit of you attaining that Weight Set Point. So the hypothalamus not only dictates how hungry you feel but it also manipulates how your body stores food, and it even dials your urge to exercise up or down. In a real sense, the hypothalamus controls you.

But what happens if your hypothalamus is damaged, and it then sets your Weight Set Point at a higher level than it would normally be?

What modern phenomena might cause that damage, though? There are three main answers: damage to the human microbiome; insufficient sleep; and the chemicals contained in modern, ultra-processed foods.

All three cause your hypothalamus to raise your Weight Set Point, subverting every effort you might make to bring your weight down. It’s almost impossible to override an automatic process.

But there is hope, for in talking to the leading scientists Alanna Collen has worked out practical ways that you can attempt to restore the hypothalamus to healthy functioning.

Do so, and you recalibrate your Weight Set Point. Your hypothalamus then conspires to bring your weight down. You won’t have to diet.

Books by Alanna Collen

The Hidden Science of Obesity: Why It’s Not Your Fault – And What Really Drives Weight Gain