There are a ton of yoghurts in the grocery store that pose as a healthy breakfast snack or breakfast alternative. They claim to be "light," low in fat or non-fat, or it could even have the total calories front and centre. But the real truth is in the nutrition facts. Most yoghurts, even Greek-style, can contain over 20 grams of sugar. This is barely under the World Health Organisation's recommendation of 25 grams of sugar per day. If the fat is taken out of the yoghurt, it's usually just replaced by more sugar.
But don't worry, since there are a ton of great low-sugar yoghurt options in your grocery store (Siggi's and Skyr are great). Sometimes it's more important to consider clean ingredients rather than total calorie count, and yoghurt is definitely one of those items you should take a second glance at before buying.