Do Carbs and Candida cause weight gain? Calories from excess Carbohydrates is usually the reason for weight gain. Barring severely low Thyroid function or genetic disorders, it's the carbs that cause Candida, Metabolic Syndrome, pre-diabetes, Diabetes Type II, Obesity, and all their side effects. Pasta, bread, sodas, cereal, candy, fruit juice, corn chips, sugars and more are not good food for Humans. Small amounts of tubers - potato, yam, ... Keep Reading >