Refined carbs are a type of carbohydrate that has been processed and stripped of most of its nutrients and fiber. They are also known as simple carbs or empty carbs. Refined carbs include mostly sugars and processed grains, such as white bread, white rice, pastries, sodas, snacks, pasta, sweets, breakfast cereals, and added sugars. They are digested quickly, leading to rapid spikes in blood sugar and insulin levels, and provide very few vitamins and minerals. Eating refined carbs is linked to an increased risk of many diseases, including obesity, heart disease, and type 2 diabetes.

In contrast, complex, unrefined, or "good" carbs such as vegetables, whole grains, and naturally sweet fruit digest slower, resulting in stable blood sugar and less fat accumulation. They are usually high in nutrients and fiber, which can help prevent serious disease, aid with weight loss, and improve energy levels. Good carbs include whole grains, legumes, fruits, and vegetables.

It is important to limit the intake of refined carbs and choose complex carbs instead. Gradually reducing the number of refined carbs in the diet and choosing healthful alternatives can make a big difference in overall health.