Swedish Nutra Vitamin C & D3 + Zinc is an excellent dietary supplement that plays a very important role in strengthening the immune system using essential vitamins. Vitamin C is essential for: Fatigue reduction Combating fatigue symptoms Defending the body against external attacks and viruses Vitamin D3 is commonly known as the sunshine vitamin and is best known for: Improving mood Supporting the immune system Zinc is also essential for: Strengthening the immune system White blood cell production Avoiding viruses and flu in the winter months Dosage: 15-30ml once or twice a day.