Low levels of Vitamin A, Folic Acid, B Vitamins, Vitamin C, Iron and Zinc all weaken immunity. This means that your most basic immune policy should be a healthy diet rich in fresh vegetables, oily fish and whole grains. A good Multivitamin and Mineral supplement can help support your immune system. Try our Multi A-Zinc, or our specially formulated Multi 50+ version, for those over 50 years old.