Magnesium, the mineral, is in a lot of foods (products) but relatively high in sun flower seeds. Out of the top my head +/- 270 mg per 100 grams (soy beans has rel. high numbers also). Magnesium is an important mineral and it tends to make one a tad more relaxed, the bowels also.... it's needed for a healthy metabolism, it's been said it helps a little against depression and even migraines. (Google 'magnesium' and find more effects)
But I'm not sure about all the qualities it has been given by some. One source of info about magnesium struck me. A Dutch homeopathic doctor, that works with autistic children also, made a study about autism in correlation with food (and supplements). He says that children/folks on the autispectrum have low counts of the metal (also iron and ZINC!) in their blood (measured via blood tests). Folks with depression too.
I'm not a big fan of homeopathy, I'm more a phyto-therapy believer myself but he opts a hole ranch of things to exclude and other food to include in one's diet (to parents) and the experiences parents had and the changes noticed in their children I found remarkable. The kids opened up to the world more, were more at ease in general, had better concentration, went better in looking others in the eye and other positive effects.
He says, eat food with rel. high counts of zinc, iron and magnesium.... seafood, meat, (bitter) vegetables, nuts and fruits. Up the vita. C intake (fruit but also via supplements), up the omega 3 intake. Lessen the intake of omega 6 and 9, of gluten or exclude it altogether and refined sugars too. Plus lots of other advices I can't remember at the moment.
I made a few attempts to translate what he said in English, to drop it on WP, but it's so technical and hard too translate in general I stopped trying. (sorry). My advice, eat good food daily, as a basis rule and 'sin' without remorse occasionally. But hey, one should suit oneself of course.
(Sorry for the long post, hope some think.... mmmm, food? What....)