A clean diet, free of processed foods, as well as caffeine, nicotine, alcohol, most drugs, and meat is very helpful for pineal as well as third eye development in general. Adding certain ingredients here and there may help some people in some ways. But keeping your body clean entirely and considering substances that society generally does not consider toxic as well as more broadly known ones like fluoride greatly attunes it to higher vibrations and the physical capacity needed for supernatural power.
What is worth having is not usually easy to attain, that is why this kind of path of developing siddhis is an extreme path, like the path of a yogi. Most people don't have the need or desire to take it this far, or the awareness of the ways some of these substances impede their psychic development. If you're not a monk, shaman, yogi, or on the master's path, it's not altogether necessary to rule out whatever substances or habits may be impeding or causing blocks in one's psychic development. But if that is your goal, to develop to the extreme, I'd recommend getting very clean for a period of several months while working on developing your third eye, and comparing the results.
"You can call me 'little sunshine'."-Crowley
Adelphia D. Blood
Sorcerer, Psychic Investigator