Very pragmatic and comprehensive view on meditation. yes, there are exaggerated claims on meditation by many schools of thoughts.If one searches the right method and continue the practice for a long period of time, one may reach some of their goals.
But please, people who do yoga aren't more intelligent than anyone else. Intelligence is the capacity to learn. How smart a person is consists of how much a person has used his or her intelligence to learn. Yogis can be just as lazy and just as ignorant as anyone else. They aren't even necessarily more relaxed than anyone else -- a yogi can put so much pressure on his or herself to be relaxed they can make themselves a wreck. People are different, and react differently. That's why there are so many meditations out there -- every religious tradition has several meditations, and there are countless philosophical traditions that teach meditations. The trick is to find one that suits you and that you're willing to take the time and effort to do regularly. Happy meditating.
Major component of every disease is worry and tension. If tension is releases, major problem is resolved and one becomes comfortable.
Meditation does help calming ourselves. For this we take help of breathing. If breathing is controlled,thoughts are controlled. There are many websites on meditation.Osho has spoken on 112 types of meditations. they beutifully narrated. Reading the writings of Osho will give complete details of meditaion with modern outlook.