What is it?Holland & Barrett Calcium, Magnesium, Vitamin D and Zinc tablets contain a combination of essential minerals. Magnesium, Calcium, and Zinc are important for multiple bodily functions, so taking a supplement ensures you get what your body needs. Calcium is needed for the maintenance of normal bones. Magnesium also plays a key role in the structural development of our bones and teeth, and zinc helps to maintain healthy bones. Calcium also contributes to normal muscle function. Magnesium contributes to a reduction of tiredness and fatigue and contributes to normal energy-yielding metabolism. Zinc helps to keep you feeling healthy inside and out. The mineral helps to support the growth of healthy hair, skin, and nails; contributes to the maintenance of normal vision and is also important for the normal functioning of the immune system and fertility.