Safe and healthy weight loss is becoming increasingly important as the obesity burden in Canada continues to grow, with 63.1% of adult Canadians classified as overweight or obese in 2018 according to Statistics Canada. Ketogenic diets are diets that are low in sugar and are very popular for weight loss. However, these diets may be associated with adverse long-term cardiovascular health outcomes depending on the source of protein supplementation (animal versus plant-based). We do not know why this is the case.