When you start taking a multivitamin, it can have various effects on your body, depending on the specific nutrients and dosages in the supplement and your individual needs. Here are some things that may occur:Increased nutrient levels: If you were deficient in any of the vitamins or minerals in the multivitamin, taking the supplement may help to bring your levels back to normal.Improved energy levels: Some people may experience an increase in energy levels if they are deficient in certain vitamins or minerals, such as iron or vitamin B12.Improved immune function: Vitamins and minerals, such as vitamin C and zinc, play an important role in supporting the immune system. Taking a multivitamin may help improve immune function.Better digestion: Some vitamins and minerals, like vitamin B12 and iron, are important for digestion.Better skin and hair: Vitamins and minerals like vitamin A[7], vitamin C, and biotin can help improve the health of your skin and hair.Improved mood: Vitamins such as B12, B9, and B6 are essential for producing neurotransmitters that affect mood. It's worth noting that these effects may take some time to manifest and that multivitamins should not be considered a replacement for a healthy diet and lifestyle.