Perhaps a good vitamin supplement would help. A magnesium deficiency can lead to malaise, fatigue, spasms, and many other problems. There are two kinds of anemia - Iron and Vitamin B. - Sometimes heart trouble will cause grooves or "spoon" nails. We would like to know what your doctor says.
they say its not calcium...heres what I found Zinc deficiency? – Yep!
Sometimes white spots can indicate a zinc deficiency!
White spots can sometimes be associated with a zinc deficiency - this was e.g. pointed out in a 1974 study, titled: ‘Fingernail white spots: possible zinc deficiency‘.
But in general, one should not expect to find a zinc deficiency when a person has only a few white spots. Because actually, a number of conditions can arise from a lack of zinc. One of the most important, which also lead to its discovery, was the stunting of growth and the lack of sexual development in adolescent boys; adding zinc to the diet brought about a rapid improvement. Skin complaints such as dermatitis and a condition called acrodermatitis in babies may result from deficiency, and there may be slow healing of burns and wounds. So zinc deficiency may show up as white spots or bands on fingernails, but probably only when other conditions manifest as well!
Calcium deficiency? – Nope!
I don't believe that it's lactose that causes that, otherwise just about everyone with lactose intolerance would have those marks. I've heard of people with Celiac getting those streaks in the teeth, because that was one of the ways my nephew's parents discovered he had Celiac. He can't have gluten or dairy either one, which is normally the issue with Celiac. For Celiac it's not lactose intolerance that's the issue, it's the casein protein that's in dairy that bothers people with Celiac. I also don't tolerate dairy, except I can eat a little bit of butter. But, I also don't have the streaks in my teeth, just the one white spot on my thumbnail and the horizontal groove in the other one. I discovered some shallow pits in another fingernail. I think it's something else, and not lactose deficiency. Besides, lactose deficiency doesn't make much sense or I would have had this happening a long time ago, like over a decade ago.
I don't know the answer to most of your questions except that either too much or too little lactose in the diet can cause white marks to appear in your nails and streaks on the teeth.