I am sure we do sometimes asked ourselves about this but never get the answer.
Here it is.
What is the difference between Yakult and yoghurt? Yakult and yoghurt are both cultured dairy products made from milk fermented with live bacteria. Yakult is unique because it is made using Lactobacillus casei Shirota strain, not the strains of bacteria used in yoghurts. This strain of beneficial bacteria is unique to Yakult. Yakult has been produced for the sole purpose of maintaining a balance of beneficial bacteria in the digestive system. Yoghurt is not a substitute for Yakult and vice versa. They complement each other as part of a well-balanced diet.{Information from Yakult Australia }