Why very low carb or keto? Why not low carb? Unpicking the terminology.
It is entirely up to you, the individual. This site is an information resource for a very low carb lifestyle.
First of all, some terminology. For practical purposes, a very low carb lifestyle and a ketogenic lifestyle are the same things. Some purists will argue with the fine detail.
A Standard diet is the same diet as recommended by nearly all governments worldwide, with some inter-country variations. But they all use the same evidence and unsurprisingly come to the same conclusions. Fat is bad because it causes heart disease. So, a low-fat diet is the way to go. Because of this, the percentage of fat lost is replaced by carbohydrate. So, you can immediately see that even though the recommendations concentrated on fat as it turns out mistakenly. For 50 years! It did not make recommendations consciously on carbs. That was just a filler to make the figures up.
So 300g of carbs, which is the recommended daily intake, is a non-scientific figure. This is recommended carb
Low carb has an equally meaningless value of 130g of carbs a day or less. ( it is often rounded to 150g) There was some attempt to define this. It was calculated that the brain needs 500 calories a day of energy to keep going. It is a remarkable energy requirement as the brain consists of just 55 or the weight of the body yet consumes 20% of the energy. When this number was recommended, this was equivalent to 520 calories. ( one gram of carbs supplies 4g of energy). At the time, it was thought that the brain had a particular need for glucose. This is incorrect. It was also believed that this needed to be supplied from food directly. Wrong again. The body can make sufficient glucose for all of its needs by healthily using protein and fat. The only use for the 150g is so that science can be done on agreed figures. If all scientists agree that low carb starts at 150g of carbs, then they can compare results. It also happens to be a rough figure at the top-end that a lot of clinicians will agree is a reasonable amount of carb to consume if you have a metabolic condition such as prediabetes or diabetes. ( perhaps 100g per day is a better figure in my opinion).
Very low carb and ketogenic cut the carbs further to less than 50g of carbs per day. Ketogenic is often defined as 30g per day, even 20g per day, but you get the idea.
This level of carbs is the minimum you could eat if you were on a mixed diet containing vegetables. There are carbs in the leaves of veg which are released on cooking. It is called cellulose. 50g of carbs will only supply 50x4calories =200 calories per day of energy. So that is less than ten calories per hour and insignificant. If you have Type 1 diabetes, you will immediately see that this is tiny. Especially when you consider that ‘in-house- you can make 180g of glucose. ( which is what the long-acting insulin is for). So, if you need 2000calories per day, 90% of that energy will come from fat and protein, but mostly fat. The result of fat burning is a molecule called a ketone. So, a very low carb diet generates ketones. It is ketogenic. Ketosis is often called a starvation diet. It can be. If you consume fewer calories than you need, then you will go into ketosis and burn fat. The ketogenic diet we are talking about here is not calorie-restricted. It is a restricted-carb diet. You can have as many calories as you want within reason. But because those calories mostly come from fat, you will be in ketosis. Natural nutritional, healthy ketosis. It does not put you at risk of ketoacidosis. ( See the article and podcast).
So, you can see that by consuming minimal calories, you will need very little insulin for your meals. Still, you will need roughly the same amount of long-acting insulin to cover the body’s production of glucose. Tiny insulin doses lead to small errors, leading to increased safety.
Some people can do recommended carb and thrive on it. The research suggests that this is around 1 in 20. Others thrive on intermediate levels of carb. Research indicates that the lower the carbs, the lower the HbA1c.
This site is going to address very low carb diets. For practical purposes, treat references to very low carb and keto as the same thing. Both terms are used in the hope of avoiding confusion when reading other articles. It is not complicated.