I am convinced that this mix of vitamins and nutrients has boosted my defense system against viruses or sickness. I have worked around people with COVID , colds, sinus infections, ect. and nothing has effected my health thus far. I have been taking this for about three months now and I can definitely feel the difference in energy levels. I like the taste, the price, and the auto-shipment plan takes out the hassle of having to worry about the next months order. Its two thumbs up from me !