Well you can substitute ingredients in your lefse recipe but you won’t get the same lefse your used to getting. Changes to the recipe can really alter how your lefse tastes, the texture,  and how it performs rolling & cooking. So if you are looking to use half & half, you may need to cut back in the amount a just a bit. I don’t think that lefse is bad for you…but maybe you can cut back on all the butter and sugar you eat it with. :)