I have started taking Nutrilite Daily Multivitamin & Minerals tablet. Are they effective or is there any side effect?

Vitamins. A good multivitamin is a good idea. It's like an insurance policy for when we don't eat right, don't sleep well, or are especially stressed. Go to a good store or get some guidance because the popular brands are typically very week and not helpful. I'm not familiar w/the brand you mention.