What are refined carbs and why are they bad?
Many whole foods that are high in carbs are incredibly healthy and nutritious. On the other hand, refined or simple carbs have had most of the nutrients and fiber removed. Eating refined carbs is linked to drastically increased risk of many diseases, including obesity, heart disease and type 2 diabetes.
There are two main types:
- Sugars: Refined and processed sugars, such as sucrose (table sugar), high fructose corn syrup and agave syrup.
- Refined grains: These are grains that have had the fibrous and nutritious parts removed. The biggest source is white flour made from refined wheat.
Refined carbs have been stripped of almost all fiber, vitamins and minerals. For this reason, they can be considered as “empty” calories.
They are also digested quickly, and have a high glycemic index. This means that they lead to rapid spikes in blood sugar and insulin levels after meals.
Eating foods high on the glycemic index has been linked to overeating and increased risk of many diseases (1Trusted Source, 2Trusted Source).
Sadly, sugars and refined grains are a very large part of the total carbohydrate intake in many countries (3Trusted Source, 4Trusted Source, 5Trusted Source).
The main dietary sources of refined carbs are white flour, white bread, white rice, pastries, sodas, snacks, pasta, sweets, breakfast cereals and added sugars.
They are also added to all sorts of processed foods.
Refined Carbs Can Drive Overeating and Increase the Risk of Obesity
A large portion of the population is overweight or obese. Eating too many refined carbs may be one of the main culprits (14Trusted Source, 15Trusted Source).
Because they are low in fiber and digested quickly, eating refined carbs can cause major swings in blood sugar levels. This can contribute to overeating (16Trusted Source).
This is because foods high on the glycemic index promote short-term fullness, lasting about one hour. On the other hand, foods that are low on the glycemic index promote a sustained feeling of fullness, which lasts about two to three hours (2Trusted Source, 17Trusted Source).
Blood sugar levels drop about an hour or two after eating a meal high in refined carbs. This promotes hunger and stimulates parts of the brain associated with reward and craving (18Trusted Source).
These signals make you crave more food, and are known to cause overeating (16Trusted Source).
Long-term studies have also shown that eating refined carbs is linked with increased belly fat over the course of five years (19Trusted Source, 20Trusted Source).
Furthermore, refined carbs may cause inflammation in the body. Several experts have speculated that this may be one of the primary dietary causes of leptin resistance and obesity (21Trusted Source, 22Trusted Source).
For optimal health (and weight), try to get the majority of your carbs from whole, single ingredient foods.
If a food comes with a long list of ingredients, it is probably not a healthy carb source.
