Consult your doctor or health practitioner before taking any antioxidant supplement. Your physician or dietician will recommend you to take them only if your body lacks nutrition. Always start with the multivitamin supplements. Take them in small doses. Do not jump to the higher dose of single vitamin supplements at an initial stage.
If taken in higher doses, water-soluble antioxidants may harm you. For instance, vitamin B6 may damage your nerves while vitamin C can lead you towards fatigue, headaches, diarrhea, kidney stones, nausea, and abdominal cramps.