Another in my ongoing series of rants!
LCHF only works because it reduces your calories.
This one drives me crazy. It's usually preceded by a grudging acknowledgement that "LCHF works, but ..." and concluded with "... so any calorie-controlled diet would work as well".
To which the obvious response is : "Well, maybe. So what?"
Positing an explanation for LCHF doesn't negate the fact that it does work, and it works very reliably, without inducing hunger or requiring you to count/measure your food.
It's true that, when you start eating low-carb, your appetite will start working properly again. If you have cravings for sweets and cakes, they will abate and then disappear. You will probably eat less, on average, than you used to; while you're in the weight-loss phase, your appetite will drop dramatically. I found that I was naturally eating about 1000kCal a day at one point.
The underlying implication here is that there's no need to eat proper healthy meals made with fresh ingredients - which is what LCHF is all about. Want to carry on eating biscuits, sauces from a jar, sliced white bread and chicken nuggets? Don't want to eat your veg? Want to eat a bag of Wotsits and a Twix instead of cooking dinner? Go right ahead. It's fine. All you need to do is "control your calories".
But that doesn't work. It's a myth. You cannot eat less junk food, and avoid the results of eating junk food. Even if you lose a bit of weight initially, you'll eventually throw in the towel and go right back to eating-to-appetite ... and another round of weight gain. I challenge any nutritionist thus: let's see you put someone on a calorie-controlled diet which includes a substantial proportion of grain-based synthetic foods (eg., sliced bread, breakfast cereals, pasta, and "treats"), and let's see them reach and maintain a healthy weight. The statistics are pretty clear on this: it almost never happens. The long-term success rate is below 5%.
The nutritionists will point to a large number of studies that show, over a period of a few weeks, that people on some kind of low-carb diet (usually "low" means 30-40% carbs, not the 10% typical for LCHF) lose weight at the same rate as people on a standard calorie-control regimen. The results are quite reproducible: they really do lose weight at the same rate for the span of the experiment.
This is an old trick beloved of the pharmaceutical industry and other shysters: terminate the experiment when you've got the result you want to see (or in the case of toxic drugs, before it all starts to go totally pearshaped). This result occurs because it takes some time for your body to make metabolic adjustments. Over a few weeks, your calorie expenditure will remain more-or-less constant, and your body will burn through some bodyfat. But if the "famine" is prolonged, it'll go into lockdown; the fat loss will stop, and you will start experiencing psychological disturbances that drive you to seek out food - preferably carbs, which will assist you in replacing that all-important bodyfat. This is a survival strategy, honed over millennia of human existence.
So let's restate the myth without the weasel words: LCHF works.
Myth : It's bad/dangerous/stupid to cut out an entire food group.
Subtle_badger's comments about "food groups" (see here: healthunlocked.com/nhsweigh... ) reminded me to include this one. It's worth repeating and adding to what she wrote there, because it's such a biggie.
The first question that arises here is: "what on earth is a food group, anyway, and what's the rationale behind this concept?"
When food exits your stomach, it doesn't look much like food anymore. It's a semi-liquid mass with a large reactant surface area, with things like carbohydrates and proteins already partially snipped apart into smaller molecules. Intuitively, then, we might imagine that certain foods end up presenting similar macronutrients to your small intestine, and we can group similar things together, but the common groupings don't make a whole lot of sense. For example, this from the NHS EatWell Guide:
These foods [that should be eaten sparingly] include chocolate, cakes, biscuits, sugary soft drinks, butter, ghee and ice cream.
In what sense is butter metabolically similar to cake, or biscuits? Butter is almost entirely fat and water, whereas a biscuit presents as polysaccharides and simple sugars. Proper homemade icecream would be almost entirely milk, cream, and (sometimes) eggs, with about 4tbsp of sugar per litre, so surely belongs in the 'dairy' grouping? Except of course it can't go there, because supermarket icecream is made with dried skimmed milk, whey protein, various vegetable oils, emulsifiers, lots of sugar, and synthetic flavourings.
Tinned baked beans (ie., junk food), nuts, and fish appear in the same group. "Soya drink" and cheese appear in the same group. Why? Your guess is as good as mine. Other countries do at least have a nuts/seeds group into which beans can properly be placed (but usually aren't).
Whatever the groupings, most health authorities tell us we have to have such-and-such an amount from each group, and it is therefore "unhealthy" to eliminate one of them. The accusation is that LCHF eliminates the grains group.
Let's be clear: humans obviously have a perfectly viable mechanism for using carbs as a fuel source. Carbs and fats are stored and burned in different ways, but we can certainly use either or both. LCHF posits a fairly modest idea: humans should not be fuelled entirely on carbs. It is the EatWell guide, in fact, that tells people to avoid all fatty foods. What was that about not cutting out entire food groups?
When you start eating low-carb, you'll find that your appetite for starch rapidly diminishes. You won't feel any great desire to eat bread, pasta or rice at every meal - in fact you'll feel uncomfortable if you do. Your body will find its own level. Even if you feel the occasional urge for fish and chips or curry with rice, your body will take these things in stride. And you probably won't want the same thing again tomorrow.
At this point it's worth looking at world diets, and noting that there is a stunning variety across the globe. Despite the fact that almost nobody eats according to the EatWell Guide, most humans (at least those who haven't discovered the joys of junk food) are healthy. If we ignore extreme-poverty diets, most people eat meat, vegetables, eggs and dairy in whatever amounts happen to be available and affordable. At some times of the year, vegetables are scarce; at others, grains are scarce. Sometimes, it's not expedient to slaughter animals for meat; sometimes it would be a huge mistake not to. Human diets vary both with geography and season.
Which brings me to a conclusion of sorts. There's an endless slanging match about the causes of obesity and general ill-health, which goes like this:
"It's carbs!"
"No it's not, it's fat!"
(repeat ad infinitum)
I would suggest, in the words of one of my favourite authors (Dr Ben Goldacre) "I think you'll find it's a bit more complicated than that".
What makes you fat and ill is bad food. Food that's been jiggled around, pumped through tubes, dosed up with preservatives, modified with enzymes, pulled apart and stuck back together again. Food that looks like food, but isn't really.
Taking the fat out of food, when nature put it there for a reason, is a bad idea. Telling people to eat lots and lots of grain-based products - which is economically and ecologically impossible in most places - is pointless at best, destructive at worst. Telling people that their traditional diets are harmful and that things in packets are good for you is arrogant and misguided. Although my posts centre around LCHF ("low carb high fat"), this diet does not involve eliminating carbs, not eating mountains of lard. As I've said, we eat vegetables, meat, eggs, and dairy, before the food scientists have had their turn. We don't care what "groups " these things fit into. We just enjoy eating them.
Here's the link to part 1 healthunlocked.com/nhsweigh...
Diet Doctor - LCHF
LCHF / IF for August? 
LCHF Lifestyle
Anyone not following LCHF
