Ask most fitness coaches, nutritionists or health professionals and they will tell you that weight control is about calories in versus calories out (CICO). After all, you can’t ignore the laws of thermodynamics!
The flaw in this simplistic reasoning ought to be obvious; a human body and a steam engine are two different things.
Our bodies have evolved complex systems of control and feedback loops in order to maintain a steady interior environment, also known as homeostasis. The man in the centrally-heated room has exactly the same internal temperature as his son who is out on the town in a t-shirt on a January evening. Our fat stores are also regulated by complex systems under the control of hormones. The idea that we evolved to fatten-up in times of plenty to prepare for lean times has no basis in reality. Our ancestors may have missed a meal or two but they were expert hunters. Meat and fat were plentiful. Fruit was seasonal and carbs were almost absent.
Approximately 3500 surplus calories are necessary to create 1lb of fat. That means that just one latte a day above your body's daily calorie requirements would add 20lbs of fat in a year, just one muffin per week would add another 5lbs as would one weekly portion of fries. But however much it seems otherwise this is not what happens. Clearly our bodies are more sophisticated than the bomb calorimeters used to calculate the numbers on our food packaging.
So why is it that at a time when there has never been so much information on diets and so many people huffing and puffing around the pavements in lycra and cycling for hours on static bicycles western populations have never been so plagued by obesity?
Put bluntly, the official advice - the advice I dished out as a coach for years - is dangerously wrong. ‘Eat less - move more’ does not work. Not if we define ‘work’ as making a significant difference in the long term. How many people who have suffered through a strict diet and exercise routine have maintained the results a year or two later? Sadly many end up worse off than before their diet. In the short term somebody who significantly reduces calories and increases exercise will lose weight - just as hypothermia does happen despite the body's best efforts at homeostasis.
So what’s going on? Why is it that some people seem to be able to eat as much as they want while others put on weight rapidly? Why could you eat all sorts of rubbish when you were young but now your weight is a constant battle?
In a word the answer is insulin.
Elevated blood glucose levels represent an imminent danger to our body. Hyperglycaemia results in serious and permanent damage to nerves, blood vessels and other organs and so the body takes urgent action to resolve it. Specifically it prompts our pancreas to release insulin which communicates an urgent message to all of our cells. It prohibits them from burning stored fat for energy and forces them to accept glucose from the blood which is turned into lipids and stored in fat cells.
Insulin levels are elevated shortly after eating any food containing sugar and takes several hours to return to normal. All carbohydrates - including bread, rice, pasta, potatoes etc - are turned into glucose in our bloodstream. The worst offenders are refined carbs - sweets, biscuits, cakes etc and surprisingly fruit juice. Carbs that break down slowly - those with a low glycemic index - do less harm than high glycemic index carbs but all of them trigger insulin. Eating fat does not elevate insulin, protein does, but much less so than carbs.
So think about the normal western diet. Cereal and fruit juice massively spikes insulin at breakfast. A latte and muffin boosts it again mid-morning followed by sandwiches for lunch. Perhaps a 'low-fat' sweet snack in the afternoon and then a main meal with rice or pasta or potatoes. Before bed perhaps another small meal so that we go to bed with high insulin levels. Just as those levels are back to a low level the alarm goes and we start again. An hour or two in the gym achieves nothing because the muscles are burning blood glucose rather than fat.
Obese people are NOT GREEDY. They are underfed. Not in terms of quantity of calories but in terms of nutrition. Eat - blood glucose spikes - insulin surges- blood sugar falls - hunger hormones elevate - eat (low-fat unsatisfying food) and repeat.
But here is the problem with insulin - over time our cells get resistant to it. Like somebody who finds they gradually need more of the same drug in order to have the same effect, as the years go by our pancreas needs to produce higher and higher levels of insulin in order to get our cells to do the job of reducing blood glucose.
Doctors test for glucose levels but there is no simple and cheap test for blood insulin. Year after year blood glucose levels remain more or less on an even keel but what goes undetected is that insulin levels are rising in order to maintain the same outcome. This insulin resistance - also referred to as metabolic disease - contributes to a whole range of diseases including obesity. Eventually the pancreas reaches its limit and blood glucose begins to rise. The doctor diagnoses Type II diabetes and prescribes insulin - much like prescribing alcohol to an addict. But the underlying problem of insulin resistance has been going on for a decade or two undetected.
It is unfortunate that this condition is even called diabetes. Type I diabetes is caused by a lack of insulin but Type II is the exact opposite. Interestingly some researchers are referring to Alzheimers as Type III diabetes due its apparent correlation to long-term elevated insulin.
The good news is that by significantly reducing carbs in the diet over a period of time the body can reverse insulin resistance and learn to switch more readily into fat burning mode in order to produce energy.
Now the practical stuff in digest form.
- Successful weight loss is based on controlling insulin levels.
- Follow a high fat, high protein - low carbs diet
- Never eat low-fat versions of any food - it will be full of sugar
- Did I mention don’t fear full fat food - fat keeps you from hunger. Cream, butter, greek yoghurt, cheese, eggs, mayonnaise are all your new best friend
- Fat you eat is not stored as fat - glucose, sugar, sucrose, fructose is.
- Try to avoid eating after early evening and if you can delay breakfast until late morning or even midday then all the better. Pre-breakfast your body will be running mostly on stored fat supplies.
- This is sometimes called intermittent fasting - there are many versions
- Ease into your new way of eating - get rid of refined carbs first and then gradually find ways of replacing complex carbs
- Check out low carb diets on the internet for lots of recipe ideas - it is a huge help if you like cooking
- Don’t take up jogging or other aerobic exercise. If you are on a calorie deficit and you increase exercise significantly your body will reduce its basal metabolic rate - the amount of energy it needs for daily activity and weight loss will become more difficult long-term.
- A 20 minute walk after a main meal is good - it will encourage your muscles to take up free glucose and burn it as fuel even after your walk is over.
- A strict version of low carb diet is called KETO where the body and brain depends entirely on fat as an energy source. Not to be confused with the dangerous condition of diabetic ketoacidosis.
- KETO does work but it is very restrictive and one mistake can trip the body back out of KETO, although experienced practitioners reckon they can turn it around quickly.
- Personally I went for a less strict low carb diet resulting in a painless 3lb per week weight loss for a total of 40lbs
- My acid reflux disappeared - and returned when I indulge
- Pains in finger and knee joints also went away
- I ate like an idiot since christmas and symptoms have returned so I am back to better eating habits again - the challenge I have now is actually preventing more weight loss.
- Strength training such as resistance bands are a good way of preventing muscle loss
So how did the normal dietary advice go so badly wrong? It is a long if familiar story of the lines between science and politics becoming blurred. The book ‘Good Calories, Bad Calories’ by Gary Taubes lays it out in detail as does ‘The Big Fat Surprise’ by Nina Teicholz. A digest version of the story is set out by Taubes in his more accessible book ‘Why we get fat and what to do about it’.
Perhaps you are wondering about the link about fat, cholesterol and heart disease. These are good questions that are beyond this post but covered in detail by these and other authors. Suffice to say that if we had been offered better advice for the last fifty years our health systems would not be at breaking point.