Unfortunately, due to the highly restrictive nature of the diet, vegans are at risk of being deficient in certain nutrients such as calcium and vitamin B12 usually found in dairy and meat respectively.

Their reasons for eating this way vary. Some vegans do it to improve their health, as research shows that a plant-based diet could lower the risk of certain diseases. Others stay away from meat because they don't want to harm animals or because they want to protect the environment.

Early vegans Evidence of people choosing to avoid animal products can be traced back over 2,000 years. As early as 500 BCE, Greek philosopher and mathematician Pythagoras promoted benevolence among all species and followed what could be described as a vegetarian diet.

Preventing the exploitation of animals is not the only reason for becoming vegan, but for many it remains the key factor in their decision to go vegan and stay vegan. Having emotional attachments with animals may form part of that reason, while many believe that all sentient creatures have a right to life and freedom.