Hi
@Vectian. Fatigue is a debilitating, as you say, possible complication of all the types of diabetes, from my understanding, for different reasons. Because it's about energy when it comes down to it, at cell level, and what is happening to us in the various complex cycles due to the type of diabetes you have, and how it plays out for you individually. I'm pleased there are plenty on this Forum who are experts in how LADA is experienced.
Because this is in a Low-carb diet sub-forum I thought it important to add something, as so many people with diabetes have type two, and low-carb ways of eating, including Keto, can be/is a go-to treatment. Lots of scientific studies backing this up etc etc. (Whether one chooses this treatment or not - that's another story.)
Fatigue, as one of the complications, doesn't happen to everyone. I haven't experienced it due to diabetes , and whilst on longterm LCHF and sometimes Keto. Now I have quite recently due to pain relief meds and a non-diabetes related condition - and - oh boy do I know what you mean by debilitating! Ghastly side effect of a medication, but that's another and non-diabetes story from me.
I
have experienced lack of energy due to not eating/fasting. Which would fit in with above posters wondering if your way of eating is contributing, and being unknowingly undernourished? (Which sounded very plausible on reading.) It felt different to what I am experiencing these days due to meds side effect. The big difference, as posters above referred to - eating food immediately ameliorated it! (Not true for me with it being a side effect of meds.)
I was under the impression that fatigue was a common symptom of having auto-immune diabetes? LADA folk step in and say!
As other posters are saying above - it's the early stages of switching to a lower carb way of eating, and probably eating more wholefoods and not UPF, that causes something called 'keto flu'. You can also explain it as withdrawal from addictive food substances, which I think there is a definite case for this explanation. Even if it 'just' from sugar and sweeteners, but it probably includes other addictive substances also that aren't really 'food' other than we eat them as part of the modern diet. (I'm reading a lot about Ultra Processed Food at the mo'.) For me 'keto flu' felt much more like withdrawal, and big changes in my gut biome and digestion, and it wasn't about fatigue. If I am remembering correctly (10 years ago.) As this is also about the health and state of one's gut biome and it's affect on our energy - one can see how it plays out differently for different individuals.