Q: I'm trying to lose weight, and a friend recently told me that cutting white bread and potatoes out of my diet completely will help. Is that true?
A: Your friend is right. Taking white bread and white potatoes, as well as white rice and white pasta, out of your diet can be helpful for weight loss. Because of the way your body processes these four foods, they can lead to cravings for carbohydrates, also called sugars. By eliminating them, you decrease food cravings, making it easier to eat less and lose weight.
The main problem with white rice, bread, pasta and potatoes is that they trigger a cycle of food craving. They release a sudden spike of sugar in your bloodstream. Your body responds to that extra sugar by releasing insulin. Insulin is a hormone your pancreas makes that allows sugar to enter your cells, lowering the amount of sugar in your blood.
Because your blood sugar level goes up after eating these foods, your body may release more insulin than it really needs. The extra insulin causes blood sugar to then drop lower than normal. When your body senses low blood sugar, you crave more carbohydrates. When you eat them, they once again raise your blood sugar, starting the cycle over. The result of this process is that you eat more food, more often.
In addition, as you eat more of these foods, your body needs to process all the extra sugar. Although some sugar is burned off as energy, most is converted into fat, leading to weight gain.
I typically recommend that patients completely avoid white bread, white rice, white pasta and potatoes for two weeks. Your body will have strong cravings for these foods, but those will decrease. Eating plant-based proteins such as nuts, beans and lentils can help. Lean meat and fish also can be good sources of healthy protein. After two weeks, you can introduce them back into your diet in smaller amounts.