Since many of our organs and tissues are made of protein, by not consuming enough protein, we would be at risk of breaking them down to a point where we become unhealthy in body function,” he said. Going past 2 grams of protein per kilogram of bodyweight, Mills said, also may contribute to increased fat stores, “because our bodies are not able to utilize a surplus amount of protein for fuel,” she said. Since many protein sources are animal-based, they tend to be higher in fat than carbohydrate-containing foods, she added, which means upping protein can mean upping fat, “which can negatively affect cardiovascular health,” Mills said.