WHAT ARE THE ADVANTAGES OF MANAGING TYPE 1 DIABETES WITH A LOWER CARBOHYDRATE APPROACH?
Type 1 Diabetes is, in essence, a hormone deficiency condition. Unfortunately, that hormone, insulin, acts by reducing blood glucose rises in response to food, amongst other things. And the food makes it difficult to manage Type 1 in practice. It is challenging to estimate carbohydrates by estimating the amount in a meal, and it is just as tricky to time insulin injections and doses to achieve smooth control of blood glucose.
Although many endogenous metabolic pathways raise blood glucose, dietary carbohydrates are still the primary source of glucose found in the body. Whereas internal metabolism can produce up to 180g of glucose per day if required, the typical diet contains around 300g of carbohydrate a day. Most of that will be absorbed as glucose, even though it may be eaten as starchy food such as grain and potato. Starchy carbs are ultimately absorbed into the bloodstream as glucose.
In the management of Type 1 Diabetes, insulin is required not only to control glucose produced endogenously (typically basal insulin), but it is also needed to manage glucose ingested as carbohydrates (usually bolus insulin). Lowered carbohydrate means lower doses of bolus insulin. The less insulin, the less visceral fat, which is not only associated with increased insulin resistance but also significantly increased cardiovascular risk.
SATIETY. Lowered carbohydrate means increased fat. People drop their craving for carbohydrate food, although managing what is essentially carbohydrate addiction needs explanation and patient support. This makes managing the eating, carb counting, bolus injecting cycle so much easier to cope with. People will be able to drop to 2 meals a day instead of maybe eating six times a day, including snacks.
THE LAW OF SMALL NUMBERS
So, it makes sense to reduce the carbohydrate content in the meal to increase the chance of getting the numbers right. Smaller doses of insulin lead to smaller swings of blood glucose, which lead to a reduction in too-high and too-low blood glucose levels, which leads to better and ultimately safer control.
It is fortunate that of all macronutrients, it is carbohydrate that is the only non-essential macro-nutrient. It is also fortunate that this non-essential macro-nutrient is by far the most likely to raise blood glucose. So, removing most carbohydrates from the diet can make a large difference to glycaemic control without leaving the patient nutrient deficient. 10.1136/openhrt-2015-000273 https://openheart.bmj.com/content/2/1/e000273
Protein also raises blood glucose but, to a lesser extent and takes longer to achieve that effect. On a higher carbohydrate diet, its effect is masked by carbs but will become apparent with the move to lower carbohydrate.
Fat has a minimal effect on blood glucose levels, so it is easy to replace carbohydrates with fat.
Low carbohydrate diets based around real, are nutrient-dense. Fat and protein contain more than enough nutrients to replace those lost in the carbohydrates. But it must be emphasised that low carbohydrate diets are not NO carb.
Leafy, fibrous foods typically have some carbohydrates, but the quantity can be managed well with lowered doses of insulin.