Is too much spinach bad for you?

While spinach is a health food, it contains goitrogens, and eating too much of it interferes in the functioning of the thyroid gland, according to GreenCravers.com. Spinach also contains purine, and consuming too much can cause overproduction of uric acid in the body, which results in gout and kidney stones.

Spinach and other leafy vegetables such as kale, cauliflower and broccoli also contain oxalates, which can become too concentrated in bodily fluids, and result in kidney and gall bladder problems. Heath coach Nina Manolson, as quoted by About.com, suggests cooking kale instead of eating it raw, and mixing it with seaweed to balance out the goitrogens with iodine.