Vitamin B deficiencies, which it is said most people have, cause problems in processing carbohydrates especially vitamin B6. There are some very good integrative medicine doctors on YouTube like, Dr Josh Axe and Dr Eric Berg, that educate on nutrition.
You need to do some studying before you just go and add supplements, as well, of course, as adjusting the diet to a healthier one. There is a lot of rubbish in the supplement market. Many products contain fillers etc that will build up in the body. You need advice over the best companies.
I noticed recently, from symptoms, that I have B6 deficiency despite a very careful diet and various supplements so took a couple of doses and saw improvements straight away which I am very pleased about. It is said that autoimmune conditioned cause one to burn through this vitamin, and also those who have been traumatized (cPTSD for me).
Taking responsibility for one's health, instead of trusting 'a pill for an ill', is so much easier for God's children as we can ask for His guidance, but we still need to do the work in understanding healthy foods.