Why do most diets fail?
You've read the statistics. 99% of diets fail. I’m not sure where that number even came from but we all know that most people (most likely ourselves included) who lose a lot of weight put it back on again, often with a few bonus pounds on top. Is it really because we all have so little willpower that we can't stick to diets or, even worse, binge after we reach our goal weight and pile it all back on (and then some)? Well wait a minute. The science of weight loss is actually much more nuanced than that...
Humans evolved hunting and gathering. We lifted our knuckles off the ground over 2 millions years ago and became what is known as the ‘modern human’ around 200,000 years ago. And for most of that time, up until just a few centuries ago actually, we have hunted for our food. There was no such thing as three meals a day plus morning and afternoon snack. Sometimes we had lots to eat (when we killed a deer or kangaroo) and sometimes we had nothing (when luck was bad). So we feasted and fasted. And then humans started growing grains about 10,000 years ago and there was a bit more continuity with food. But we still had to go out and pick the grains, crush it, and turn it into something you wanted to eat. Grabbing a snickers bar when we paid for our petrol wasn’t really an option.
So the body evolved to deal with this. When food was abundant, we ate our fill and stored up the extra as fat for those times when Skippy was just too fast to catch. The hormones that control appetite like ghrelin, and feeling full (the satiety hormone leptin), and glucose regulation in the body (insulin) have evolved from this hunter-gatherer way of living.
So contrast this with modern living in the Western world. Everywhere around us there is food. The supermarket with its overflowing aisles (save 99 cents!), the work break room with bagels and birthday cake, wine and cheese at book club, huge mountains of muffins when we stop to get a coffee. Its like the whole world is trying to feed us 24/7! And it’s all making us fat.
But it is not as simple as increased calories and more sedentary time in front of the TV, otherwise known as the Calorie In/Calories Out (CI/CO) theory of weigh management. Weight and metabolic rate is actually managed by a series of hormones that scientists realise now are much more critical to how much we weigh, and defending our weight set point, than previously thought.
When we eat, insulin is released. This is an extremely important hormone as it helps regulate the level of glucose (energy) in the blood. Constant levels of glucose are critical for maintaining all body functions including the brain. The body is a fine tuned machine and it is very good at doing this. But the modern diet makes that a lot harder for the body. If we eat a diet high in sugar and simple carbohydrates (processed foods like white bread, crackers, rice, pasta, packaged snacks etc), the body is working overtime to maintain optimal levels. Too much glucose in the blood signals to the body it needs to store the extra as fat to be kept for a rainy day when there won't be a lot of food around (remember Mr. Hunter and Mrs. Gatherer?) Eat like that often and every day and the body just keeps storing it on your butt, hips and thighs (or wherever your particular genetic lottery deems is the right place). And added to that, if you eat like this all the time, your body keeps secreting more and more insulin and you start to become resistant to it. What does that mean? In a nutshell, you get really good at storing fat but not so great at burning it. Your body uses the sugar in your blood and will then burn glycogen (stored glucose in the liver and muscles) and make your super hungry all the time so you eat more and more and supply it with enough ready-to-go glucose in the blood so you never have to use up all those fat stores. Insulin resistance, also known as Metabolic Syndrome, is the precursor to Type 2 Diabetes (something you definitely don’t want to get).
Does the CI/CO method help you lose weight? Absolutely. If you eat less than you use each day for an extended period of time, you will lose weight. But the key is can you keep it off? Scientific evidence proves that prolonged low calorie diets and excessive exercise can actually lower your metabolic rate. That means, if you were 80 kgs and you did a great job managing your CI/CO on the Grapefruit/South Beach/Atkins/fill-in-the-blank diet and dropped down to 65 kgs, your metabolic rate (the amount of energy you burn each day) at the end will actually be lower than someone else who is the same height and weight and never subjected themselves to a prolonged calorie deficit (this includes using excessive exercise to make a calorie deficit by the way).
Ever wondered why there is never a Biggest Loser reunion show? It is not because they are all lazy and really want to be fat again. Those guys and girls and their minders spent that whole show focused on their CI/CO. They worked out like crazy people and think how much damn lettuce and broccoli they ate to get where they got? Well there is actually a scientific reason why most of them put it all back on. The body thought, hey, things have changed and now there is no longer enough food around and we have to run around a BLOODY LOT to get any food so we need to protect ourselves and lower the amount of energy we use every day. Their bodies adapted and lowered their metabolic weight by approximately 500 calories a day. That means they have to eat give or take 500 calories less (forever) than the next bloke who is exactly the same height and weight as their new look-spanking bod. If you are like me and like reading scientific studies, you can here or a slightly more reader-friendly article about the study in the New York Times. This was a study done on 16 Biggest Loser contestants and yes it is real science even if it is not fair. And a lowered metabolic rate and hormones telling (screaming at) you that you are hungry is hard for anyone who has been on a low-calorie diet for extended period of time to fight against.
So what can we do about it? Well the first thing we have to do is cut back on the sugar, processed foods and the artificial sweeteners (more on that in another post but new research shows that artificial sweeteners have just a detrimental effect on insulin as the real thing so why bother?) If you want to lose weight and feel healthy, that is the first and most important thing you can do. The next is appetite correction, which is exceptionally important if you want to get those hunger hormones under control and take charge of your eating. And we want to make sure we don’t lower the metabolic rate. This is very important for optimal health but if you want to lose weight and keep it off. And low calorie diets are not helpful for appetite correction. Sure they can help you lose a few or a lot of kilograms, but they don’t help you get in control of your hunger hormones so your body is working against you keeping it off long term. Those hormones are primal and they are strong, they will defeat willpower every day and twice on Tuesday.
The key to appetite correction and managing the weight and appetite hormones is Intermittent Fasting or IF as it is also known. Don’t be scared off by the word fasting. It is fine to be hungry every now and again. Some of us haven’t been hungry for years! And the best thing about IF is there are no shakes to buy, no special supplements, no expensive programs. And there are a few different ways to skin the fasting cat to suit your lifestyle (and to make sure you don’t mess with your metabolism). In this article lay out some ways to fast that are proven to work (by actual science, not so called celebrity weight loss experts).