Although it may be fair to say I don't exactly shy away from controversy, there is one topic I have long since learned to generally leave to the more battle-hardened, as it so inevitably turns so volatile so quickly. Is it vaccines? Moon landings? Whether Paul really, seriously, is dead? No (although the latter is certainly a contender... And he is.... *ducks*). It's diet.

I know from extensive, invective-laden experience just how contentious this subject is, and that - no matter what your views - there are thousands of people lurking in the darkest recesses of the internet, who are just waiting to pounce upon you and tell you that, not only are you wrong, but sick, evil, soon to die, and contributing to imminent global catastrophe of one sort or another.

To sum: I know there are people who don't agree with me. That's fine. You don't have to. You may, however, feel entirely excused from any obligation to tell me so (loudly, and vociferously, and expletively..), but as it's a subject I've read a lot about, I've come to some definitive conclusions. I don't push my views on anyone, but the subject came up in a discussion with a friend the other day, and she was interested in what I said and asked me to expand upon it in writing, so I will...

My friend was asking for advice specifically on managing weight and blood sugar (diabetes or pre-diabetes), so that's the angle I'll approach the treacherous topic from...

The first thing to be aware of is that, unsurprisingly, all the "conventional wisdom" on diet as pushed by the usual suspects (NHS, government, schools) is wrong. Remember, the same people who try to sell you three vaccines a year for a mild cold virus, also tell you to eat a low-calorie, low-fat diet containing plenty of starch and whole grains - and they give this advice for the same reasons: customer creation for the pharmaceutical industry, and early death for the depopulationists.

So, the conventional wisdom on diet is not just wrong, but (like most things establishment) completely inverted. The human body actually needs plenty of fat, minimal (if any) starch, and you really, truly don't need to worry about calories.

Not convinced? Let me explain...

Modern, conventional dietetics are based on a fundamentally flawed, and really quite preposterous, belief, which is that the human body functions the same way as a bomb calorimeter. Those are the instruments used to measure calories in food, and so, it was decided by "the experts" that, because a bomb calorimeter burns all calories at the same rate, so does the human body. That the human body functions on a "calories in, calories out (CICO)" mechanism, whereby, regardless of the source of the calories, if you consume more calories than you burn, you gain weight, and if you burn more calories than you consume, you lose weight. To your body, a calorie is a calorie, regardless of where it comes from.

It's a nice little theory. And it's completely wrong, because it fails to take into account a rather crucial little distinction, which is that a bomb calorimeter is an inanimate object, and the human body is a complex, finely tuned, biochemical living organism. And that distinction matters.

The human body does not function like a bomb calorimeter, it does treat calories from different sources differently, and CICO-based diets don't ultimately work - which is why nearly 100% of people on conventional weight loss programmes put all the weight back on and more within five years. It's not because they failed. It's because the diet failed, as it's designed to, to keep you in a lucrative trap of pricey diet supplements, weight loss classes, gym memberships, and, ultimately, pharmaceuticals, to manage the weight-based problems you've now developed as you haven't been able to lose weight and keep it off through calorie-controlled diets.

But why don't low-calorie diets work long-term?

To understand why they don't, it's first important to understand the mechanism by which your body stores fat, and it's not to do with calories. Rather, it is hormonal. There's a key fat storage hormone in your body, and it's called insulin. Insulin tells the body to store fat and the body cannot do this without insulin's signal. That is why, if insulin-dependent diabetics stop taking their insulin, then, regardless of what or how much they eat, they will lose weight.

So, the key to effective and lasting weight loss is really quite simple - keep your insulin down, but safely (note: if you are an insulin-dependent diabetic, stopping taking it is extremely dangerous). How do you do that? You simply avoid foods that prompt a strong insulin response.

Insulin's key function in your body is to bring down high blood sugar levels, since high blood sugar is dangerous. Certain foods convert to sugar in your body - and therefore prompt a strong insulin response - and certain foods don't, so how much insulin you produce, is entirely dependent on what you eat.

Anything that tastes sweet, including fruit, rapidly turns to sugar and prompts a substantial insulin response, as does anything starchy, such as bread, potatoes, pasta and rice. All of these foods quickly turn into sugar once eaten and produce a significant insulin response. And insulin is like many things (alcohol, caffeine, etc.), in that, the more you are exposed to, the more of a resistance you build up, and so the more it takes to have the same effect.

The reason teenagers are often able to eat anything and remain slim is not because they have "fast metabolisms", but because they typically have an excellent insulin response. They only require small amounts of insulin to bring down their blood sugar, because their cells - having not been bathed in the hormone for many decades, as middle-aged cells have - are very sensitive to it. Small insulin response = small (if any) fat storage.

However, over time, if they continue to eat a standard Western diet, with starchy foods at every meal (bread, pasta, rice, potatoes), their cells start to become resistant to insulin, and they require more and more of it to get the same response. As mentioned previously, insulin is the fat storage hormone, so the more you produce, the more fat you store. As you get older and become more insulin resistant, you produce more and more insulin at meals, meaning more and more fat gets stored. That is why people typically gain weight as they get older. Not because "your metabolism slows down" (it doesn't in any significant way, not until you're actually elderly), but because your insulin resistance goes up.

This is also why weight gain is associated with diabetes, because the same insulin resistance that is causing you to produce more insulin and therefore gain weight, is also the precursor to diabetes, which, in its type 2 form (the type associated with lifestyle, weight gain, and ageing) is a form of extreme insulin resistance.

The way to resolve both of these problems - the insulin-resistance/diabetes and the weight gain - is to stop producing so much insulin at meals. How do you do that? By avoiding the foods that trigger a strong insulin response, namely, anything sweet and anything starchy. Instead, base your meals on protein (which has a very small insulin response) and fat (which has almost no insulin response at all). This is basically the premise of the Atkins diet and the Keto diet, both of which have been pilloried in the mainstream press and by the NHS, because they work and therefore eliminate your need for pharmaceuticals or other lucrative interventions.

Very sadly, where it comes to the macronutrients - carbohydrates, protein, and fat - vast swathes of the Western world have been made literally fat-phobic: they are frightened of it in the same way an arachnophobe is of a spider. Fat-phobes shrink away from fatty meat and oily dressings as if these foods will instantly make them obese, but this really is such a sick and insidious lie, because, in reality, the exact opposite is true. So, please let me be really, emphatically clear on this (and I, unlike NHS doctors getting pharma kickbacks, have no reason to lie): dietary fat alone is biochemically incapable of turning into body fat, because the creation of body fat requires the presence of insulin, and when you eat fat on its own, or with protein, the insulin response is too small for any significant fat storage to occur. You literally cannot get fat just eating fat (hence why 'fat fasts' - where 80-90% of calories come from fat - are the fastest way of losing weight).

Conversely, add a few slices of bread, a serving of mash, or a big bowl of rice or pasta to your fatty steak or oily salad, and THEN you will produce the insulin that will store some of your meal as fat. But only then. Without the carbohydrates, your body will simply not produce enough insulin to store the food as fat.

So what should you eat to minimise insulin production and therefore lose weight? You should primarily eat high-quality protein and good fats, meaning, all kinds of meat, poultry, fish, seafood and eggs (and don't exclusively go for lean cuts, include the fatty steak, the chicken skin, the egg yolk, because a) fat is very satiating so will fill you up quicker than lean protein, and b) fat is often where the nutrition is found. Nature typically surrounds protein with fat, and this is for a reason).

You can also eat some dairy, such as cheese, butter, and ghee, but be careful with milk and yoghurt, because these contain lactose, a sugar, so can crank the carb count up. And, cardinal rule - whatever dairy you do eat, never, ever get low-fat! Always get full-fat everything. The demonisation of dietary fat in the Western world over the last 50 years is just another devious psy-op, and all the health conditions that have been blamed on it - obesity, diabetes, high blood pressure, heart disease - are actually caused by high-carbohydrate (e.g. high sugar) diets. In effect, fat has been blamed for what sugar did, because this suits the food industry (starches are much cheaper and easier to produce than high quality fatty proteins), the pharmaceutical industry (high, carb, low-fat diets will have you on an array of lucrative medications much quicker), and the death industry (low-fat, starch-based diets will kill you quicker). Whenever anyone's pushing an agenda, you always have to look at the interests behind that agenda, and it's always the usual suspects and their pharmaceutical fixations pushing low-fat, high-starch diets.

You don't just eat meat and dairy on low-carb diets, though (although you can - some people do and swear by it), you can also freely eat low-starch vegetables, such as lettuce, cucumber, courgette, peppers, olives, avocado, and green veg - just be careful with root vegetables like carrots and parsnips as these are quite starchy.

The key thing is to keep your overall carbohydrate count low, which you will naturally do if avoiding all sweet foods and starches. Everyone's different where it comes to exactly what their carbohydrate tolerance level is, but broadly speaking, under 100g a day constitutes a low-carb diet, and under 50g a day constitutes very low-carb (low enough to put you into "ketosis", from where the Keto diet gets its name. This will cause very rapid weight loss, but is difficult to sustain in the long-term, so I wouldn't advocate it unless you need to lose weight extremely quickly, e.g. in preparation for surgery). You can easily find a food's carb count on its packaging or online.

If you're eating this way, you will quickly lose weight and reverse insulin resistance, but to maximise results even further, you can try intermittent fasting. This essentially means having an "eating window" each day in which you eat all your food, and then a longer period - say 16 hours - where you do not eat at all, and only drink water or black tea or coffee. Conventional wisdom tells you to eat "little and often", but actually, this is really bad advice, as it means insulin is constantly up. If you can manage a significant period each day without eating anything, it means there is a long period where your body is producing no insulin at all, and so this will optimise weight loss and improve insulin resistance.

People only feel the need to eat "little and often" when they are on the blood-sugar roller-coaster produced by high carb diets and insulin. What happens on a conventional diet is you eat a meal - say, a bowl of low-fat cereal with skimmed milk, a banana, and whole-wheat toast with low-fat spread - and all these foods very quickly turn to sugar, so your blood sugar goes through the roof, and your body pumps out industrial amounts of insulin to get it down (since high blood sugar is dangerous). So then, after insulin has worked vigorously to rid your bloodstream of sugar, your blood sugar levels crash and you feel cranky and tired - and hungry.

If you get out of this cycle by avoiding foods that have a high insulin response, your blood sugar will remain stable for hours and you will be able to go much longer without eating. Just see the difference if you have bacon and eggs for breakfast, as opposed to "healthy" cereals, wholegrains, and fruits. Breakfasts consisting of protein and fat rather than sugary carbohydrates keep you full for hours and you probably won't even feel like lunch.

On the subject of breakfast, though, it's the easiest meal to skip if you're doing intermittent fasting, and many people who do eat breakfast, only do so out of habit, a habit it is really easy to train your body out of. If you find you get hunger pangs first thing, you can drink a "bulletproof coffee", which is coffee mixed with butter and MCT oil, rather than milk and sugar, which instantly kills hunger pangs because of all the satiating fat, but, as it has zero carbs or protein, it has no insulin response, so your body is still reaping all the benefits of fasting.

I do understand totally that anybody who has been on the receiving end of decades' worth of state propaganda about diet (which is pretty much all of us) is going to balk at the idea of liberal amounts of butter and oil, because, all those calories! You can't possibly lose weight consuming so many calories! Well, you can, because calories don't matter in the way that we are taught they do. They matter, but more of a concern is not getting enough, than getting too many, because if you don't get enough - and many people on conventional weight loss diets do not - then your body responds by slowing down your metabolism, which is the last thing you want if you're trying to lose weight. This is the fundamental point where CICO (calories in, calories out) diets fail, because they treat the human body as a dumb machine rather than an ultra-intelligent living system.

You need a certain amount of calories every day to stay alive - to keep your heart beating, to run your respiratory system, to keep you warm, and to keep your brain working, amongst other things. Even if you stayed in bed all day and didn't move a muscle, you would still need a certain amount of energy to run your body. This is called your basal metabolic rate (BMR) and for the average person, it's around 1,500 calories a day.

From the moment you get out of bed and start doing things, you start to require more calories, and the more active you are, the more you need.

So, the problem with conventional, CICO diets is that they tend to put the daily calorie limit so low, that many people are not getting the calories they need to sustain basic, everyday activities, and some diets don't even provide enough to meet fundamental BMR requirements. If you are typically taking in less than around 1,800 calories a day, then your metabolism will slow down. One way you know if you have a slow metabolism is if you are always cold. Your body expends a lot of calories maintaining your temperature, so if you're not eating enough, one of the first things it does is reduce your body heat to conserve calories.

This is because your body - not being an inanimate object such as a bomb calorimeter, but rather, a very intelligently designed living system devoted to keeping you alive - notices when there is a drastic reduction in calories, and perceives it as an emergency. Your body assumes there is a famine and not enough food available, so, in order to protect you and maintain your basic functions on the reduced rations available, it slows down your metabolism. Because traditional weight loss diets are both low calorie and carbohydrate-based, a conventional dieter is now in the worst possible position for weight loss, where they have a slowed metabolism and relentlessly high insulin, a situation made even worse by the "eat little and often" advice.

Low calorie, low-fat, "little but often" diets are literally the worst thing for weight management, for insulin resistance, for diabetes reversal, and for other conditions, like depression (low-fat, low-calorie diets will make you depressed - it's no coincidence that when the bookshops started filling up with low-fat diet books, they started filling up with self-help books on depression, too), because they slow your body down whilst keeping insulin and blood sugar up. Then, this already catastrophically bad advice is made even worse by that other insidious little CICO lie, exercise. Now, don't get me wrong, exercise is good for you. It's good for muscle-building, mood-lifting, blood pressure reducing and more. It's a good thing. I'm pro-exercise.

However, it plays effectively no role in weight loss and can actually predispose people to fat gain, because, what do you do if you want to work up an appetite for a big meal? You do some exercise. Exercise makes you hungry, and because its role in weight loss is vastly overestimated by conventional dieters, they'll often think, well, I've done all that exercise and now I'm starving, so I'll have a big bowl of pasta with some crackers and low-fat spread, all washed down with a big fruit smoothie. Therefore, insulin goes sky-high and fat is stored. By all means exercise, it's definitely good for you, but unless you're eating right, it won't cause you to lose any weight. Weight loss is virtually entirely controlled by diet, to the point that you can literally sit on your sofa all day for months, and as long as you're eating low-carb, you will lose weight.

So, to sum, to lose weight and keep it off, and to reverse diabetes and insulin resistance, you need to: 1) Eat enough calories to fulfil your BMR and daily activity requirements, so your metabolism doesn't slow down. You don't need to calorie-count - just eat until you're genuinely full. Your body knows how many calories it needs. 2) Keep insulin down by avoiding sweet and starchy foods. 3) Give your body a break from any insulin production by practicing intermittent fasting, which is basically just skipping breakfast, and having a bulletproof coffee if you get really hungry first thing.

Once you've reached your goal weight, you don't need to stay on an ultra low-carb diet and can reintroduce some carbs without gaining weight - but a lot of people find, once they've gone low-carb, their overall health has improved so much - not just weight loss, but improved energy levels, better mood, and reduced aches and pains - that they don't want to.

I could go on about this subject for a lot longer (you probably won't find that too hard to believe, if you're a regular reader...), but I won't (will wonders never cease?!), as I just wanted to give a brief overview - yes, the above is my 'brief'! - to encourage people to look into it more for themselves, because there's so much brilliant information out there by people far more learned than I. Some excellent further resources are...

Fat Head - a nutrition documentary made by a comedian-turned-health-writer, who challenges the conventional wisdom on diet (and even his doctor is forced to grudgingly agree with him). Very funny and informative - "edutainment" - and highly recommended.

Fat Head follow-up - a brief update on what else the film-maker has learned about nutrition in the years after making the film.

Why We Get Fat - a great book on what causes weight gain and diabetes - and bow to reverse both.

Fast This Way - a good introduction to the benefits of both intermittent fasting and low-carb diets

Also, do look up Dr. Aseem Malhotra, Dr. Jason Fung, and Dr. Zoe Harcombe, all of whom are proponents of low-carb diets and give out lots of great information and advice.

Oh, and if you're thinking I've left a major food group out - the liquid one! - then, yes, rest assured, you can drink alcohol on a low-carb diet. Red wine, dry white wine, and spirits with low-sugar mixers like soda water are all very low carb, and - contrary to popular belief - beer is actually reasonably low carb, too, having about 3.5g of carbohydrate per 100g, making it a much lower carb beverage than fruit juice, smoothies, or even milk. You can also get specialist low-carb beers, where the carb count is even lower.

So, even if you disagree with everything else I've just said, at least we can all agree on one fundamental thing - that beer is good (since you can even get vegan, gluten-free, unalcoholic versions, if you are that way inclined...)