There's three main philosophies for going low-carb. Or at least, three main philosophies I have heard of and all three get confused with each other. If you want another look at some low-carb diets, check out @kiwideb's one here
They are: Paleo, Ketogenics, and the Whole30 Challenge. Of the three, Whole30 is more of a diet than a lifestyle change, but I'm bundling them all in the same ballpark.
All three have the same initial focus - to get away from pre-packaged, over-processed, over-altered "foods" currently on the market, but all three have vastly different ways of doing it.
Keep in mind that I am not a medical professional nor a dietician. This is only a layperson's view for other laypeople.
Whole30 Challenge
Whole30 is all about eating whole foods for thirty days. As long as it's all natural, it's on the menu. Its focus is more on vegetarianism/veganism than it is getting away from the carbohydrates, but, if you're careful, you can avoid most of the carbs anyway.
Whole30 avoids anything artificial. You sweeten with honey or maple syrup, and some count cooking meat as 'processing'.
The rules to Whole30 include not recreating processed foods [eg: KFC imitations, burger imitations, etc.] and staying off the sweeties. However - people cheat and eat sweet treat foods like apples and nut butter that can pack on the pounds.
You can eat out on the Whole30 diet, but you have to bring your own salad augmentations.
Yes, there are some health benefits from staying away from processed foods, but not enough for diabetics like my Hubby. Or people who are allergic to most iron-rich vegetation like me[1]. Most people can do this and most people will feel fantastic.
Then they pat themselves on the back and head straight for their chocolate stash.
Paleo
Paleo is short for "Paleolithic" and holds that all proper eating happened before humankind toddled out of the stone age. That said, "Stone age" is relative. There were cities in Africa while Europeans were still hunting mammoth with flint spears.
Sources of food, again, avoid all the heavily processed stuff, as well as modern grains (because of genetic engineering). BUT, you can make yourself some nice tasty fakes of modern luxuries, if you source it and make it all yourself.
Paleo cuts right down on the dairy, unless you're of European origin. If you do your research, you'll find that our pale primate pals were doing something involving brewing milk for some time before we[2] discovered civilisation as we know it.
The basic rule of nature is, if you can't pluck it, kill it, or obtain it in a theoretical stone age, don't eat it. Some Paleo sorts make their own bread out of heritage grain. Some prefer to stay away from seed crops. It's variable. If you want Paleo bread, you can have it, but it's denser and crunchier than any bread the mainstream is familiar with.
It is possible to dine out on Paleo, but the selections of eateries are limited.
Yes, you can ferment things with the Paleo lifestyle. Fermenting, drying, and even pickling were all common methods of preservation. Though our ancient ancestors were more likely to salt-pickle anything rather than use sugars.
And there are some Paleo people who won't use food processors or modern technology. It's all about what you're comfy with doing. Personally, I'm not about to thinly slice my root vegetables with a flint blade any time soon.
Ketogenics
Ketogenics, Keto for short, is more about the science of eating, rather than banning or approving foods. It tends to get you away from the processed stuff, but that's only because you can't trust any of it to not have carbs. It also gets you away from the sweet fruits, because too much sweetness is bad.
Keto takes in the philosophy of both Paleo and Whole30 and turns it into a complete set of options. It's especially good for anyone suffering diabetes, has shown improvement in people with neurological conditions, and generally improves health.
Not to big-note it too hard, but it's the fountain of youth on a plate.
HOWEVER: Keto is very easy to get wrong. It's hard to get over the concept that fats are evil and must be avoided. It's very hard to give up all those tasty, easy carbs and realise that they were bad for you. And it's especially difficult to eat out.
Fast food of just about every kind is on the no-no list. Either because of bread, chips, or something in the sauce.
With all good luck, I should be talking about hidden carbs and the Bliss Point, come tomorrow.
The key point about Keto is controlling exactly what goes into your body. There are no shortcuts. Want to have tomato sauce[3]? Cool. Just start with the actual tomatoes and the vinegar of your choice. Want chocolate? Get the darkest chocolate you can find(70% cacao or better) and go from there. Want crispy, deep fried chicken? Start with the chicken parts and make your own crumb coating out of almond meal, herbs, and spices.
And, if you want to speed the process along, fasting windows are recommended. I usually don't have breakfast until ten in the morning at the earliest. Hubby generally eats one meal a day.
I find Keto to be the most flexible of the LCHF lifestyle options. Can't have spinach? Cool. You can get your iron from other sources. Can't have the fats off meat? You're still good, because cheeses of all kinds are your new best pal. Hubby is diabetic, so we're staying away from the legumes and pulses, but there is literally an entire world's worth of things that we actually can eat.
Or, if you don't like the idea of fasting, just stick with:
Low Carb, High Fat (LCHF)
Reduce your net carbohydrate[4] intake to fifty grams or less and up your dietary fat to compensate. There's a few diets that already do this without seeming to, and that's because the fats are in Mainstream-healthy things like avocado, fatty or oily fish, and olive oil.
It's slightly more flexible than Keto, in that you can have more low-carb food options and even get a bunless burger from an obliging fast food eatery.
You still have to avoid just about every food product that's not a whole food, mainly because the industries have figured out how to add sugars to everything. "All natural" does not mean "all good", and you have to scan your nutritional panels for carbohydrate values of ten or less. Less is preferable.
We spent millions of years eating seasonal food that we processed ourselves, if we processed it at all. Then humans invented farming and it all went south.
And for those smarty-pants who say that the average lifespan pre-civilisation was thirty... I give you this: The leading cause of death, pre-civilisation, was sabre-toothed tiger and not, as it is today, coronary/cholesterol issues.
(Picture © Can Stock Photo / gajdamak)
[1] TMI Time: Spinach, Silverbeet, and most cabbages give me a bad case of "The Trots" with optional vomit. Not a fun time for my good self.
[2] Winters in the ice age were harsh and long. Any kind of food that got better with age was a bonus. Also, you may have guessed that I am whiter than creamed rice.
[3] I do believe Americans call it 'ketchup' for some reason.
[4] Net carbohydrates == Total carbohydrates minus fibre grams for all those nations who do not include that particular part of carb math on the labelling.