Leptin, ghrelin, incretin, insulin, glucagon can all be jacked in various stages that cause your body loads of inflammation and to store fat and 'grow' very quickly (anabolic state) and do all sorts of messed up things.

When these are not working properly even adopting to 'healthy versions' like oats, black beans and whole grain even gluten free breads etc are often not effective & the weight still piles on and even more so in conjunction with un balanced fat and protein intakes, which anyone who exercises is told "get your protein".

The reality is if your metabolically screwed you need to get those hormones working again- that means losing fat around your pancreas, get into the solid good bmi range, reducing glucose and insulin levels- get all those things stabilised and THEN you can figure out a whole foods whatever carb intake you want.
HOW?
The composition of your food matters, calories often don't it’s the MAKE UP.
What supplements/medications are you taking? are you happy with them and are they the right dose? If you are adopting a low fat, protein approach then eating too few calories is going to cause an issue. If you are going low carb is that whole food or heavily processed? If you eat ultra processed versions of food that’s also going to cause issues (vegan meats, protein powders and bars). If you are eliminating food groups then how will you be getting the micronutrients needed? Again some one without strong insulin resistance may be able to get things back by simply going 'whole foods' (including things like potatoes, bananas) someone who is very insulin resistant is going to have to make significant changes and those can vary greatly depending on needs.

Sleep plays a HUGE role and random exercise is like a little extra helper and daily EASY exercise is absolutely essential to having a well functioning body.

Take a look at the various things that impact your metabolic health...I know its a bit daunting, the more info you have the more informed choices you can make.

THINGS TO LOOK AT?
What is the make up of your nutrition?
What is your waist circumference?
What are your blood tests telling you? normal hba1c but sky high c-peptides & fasting insulin? what about your triglycerides.
Which areas do you think you may have some issues with? (split shift night workers have their systems under immense strain with jacked sleep).

What to do about it all?
SEE your Dr get diagnostics, remove the guessing, ask them questions and if they don't know ask them which expert they should talk to.
If you find yourself spinning wheels, you can use a health coach to get things where you want.