Tzatziki can be compatible with a ketogenic (keto) diet if it is prepared with keto-friendly ingredients and consumed in moderation. Traditional tzatziki is made with yogurt, which contains natural sugars in the form of lactose. However, there are low-carb or Greek yogurts available that have reduced carbohydrate content. Opt for full-fat, unsweetened yogurt or Greek yogurt to minimize carbohydrate intake.