Type 1 is managed by insulin. It is not managed by diet.
There are two types of insulin you take
- long acting or basal. Our liver drips glucose into out blood throughout the day and night. The purpose of this basal insulin is to work with that liver drip to reduce the glucose in our blood.
- short acting or bolus insulin. Whenever we eat, our body will convert the food into glucose so we need insulin for that glucose. The amount of insulin we need is dependent upon what we eat. This is mostly carbs - hence carb counting However, our body needs glucose and, if we do not eat carbs, our body will find it elsewhere - by breaking down protein. So, if you eat no carbs, you will need to calculate your insulin dose based upon your proteins. As protein is converted to glucose at a slower rate than carbs, some see this protein bolus as a "correction". If you miss a meal and eat nothing, you will not need a bolus injection - unless it is a correction because your BG is too high.
Then there a few other things to consider
- The rate at which our liver drips glucose is not exactly the same throughout the day but the slow acting insulins assume it is the same. Therefore, we may have some "spare" basal insulin in our blood when our liver is producing less glucose. During this time, it may be possible to eat something without the need for a bolus insulin.
- We also take fast acting carbs when our BG gets low - we do not need insulin for these carbs.
- You may also be advised that you can have a snack of 10 to 15g of carbs between meals without insulin. I am not sure about the reason for this. It could be "mopping" up the "spare basal" or it could just be your DSN helping to minimise injections to only with meals when you will need to add a correction to your carb counted insulin.
- There are other things which can affect our BG which may result in us needing more (or less) insulin such as illness or stress.
Sorry, that is a long winded way of saying "it depends" but you cannot avoid all insulin by eating no carbs. You will always need basal insulin and it is rare to need no insulin when you have a meal.