Methylcobalamin is regarded as the final and therefore the most bio-available form of Vitamin B12 (Cobalamin) and when dissolved under the tongue it is not lost in the digestive process but gets straight into the bloodstream significantly increasing its absorption and effectiveness. Vitamin B12 is absolutely critical for good mental and physical health. It is the largest and most structurally complicated vitamin and can be synthetized only by certain probiotic bacterial species. Vitamin B12 is essential for the DNA (cell's genetic material) and works with other B vitamins to form all types of blood cells. It supports brain function (memory & focus), immune system, energy production and metabolism of fats, carbohydrates and proteins. It helps to keep our heart and cardiovascular system on track by maintaining normal homocysteine levels. Vitamin B12 plays important role in fertility and pregnancy. It is crucial in the maintenance of the nervous system and in preventing damage of the myelin sheaths, the insulating material that surrounds nerve cells. Also children require constant Vitamin B12 supply for healthy development of the immune and nervous systems and to maintain proper appetite. Unfortunately, due to many different nutritional, physiological, environmental and lifestyle factors Vitamin B12 deficiency is a common and growing problem today which may lead to anaemia and numerous unpleasant symptoms including mental fogginess, poor memory and concentration, fatigue, irritation, feelings of apathy and lack of motivation, mood swings, muscle weakness, or sleeping problems. Lack of this vitamin may also contribute to weakened immunity and recurrent infections, damage of the myelin sheaths of the nerve cells, birth defects, age-related hearing loss, or increased homocysteine levels and higher risk of cardiovascular problems.