If you are sensitive to dairy… it’s neither. However if you tolerate dairy well…
Both yoghurt and kefir are cultured milk products but they contain different types of beneficial bacteria.

Yoghurt: contains around 1-5 strains with 6 billion Colony Forming Units (CFU). There are around 6 grams of protein in most yoghurt brands per cup.
Kefir: contains around 12 different strains of live and active culture and 25-30 billion CFU, it is also up to 90% lactose free so most people that can’t tolerate lactose can tolerate kefir. There are around 11 grams of protein in one cup of kefir.
For this reason kefir wins as it is higher in protein, lower in lactose and has more probiotic benefits. If you have a compromised digestive system it is really important to introduce kefir slowly as it can make digestive symptoms worse.
Our favourite brand available in Singapore are:
Miss Kefir for fresh products made in Singapore
Kefir by The Collective on RedMart,
Coconut Kefir is a great substitute for those that are dairy intolerant - available at Little Farms.