If you retain fluid after downing a sugar-laden soda or after a meal high in simple carbohydrates, you're not alone. A diet high in simple sugars can cause water retention, which leads to swelling, especially in your hands, fingers, legs, feet and face. One reason low-carbohydrate diets cause a large weight-loss in the first week is the loss of water weight related to carbohydrate intake. Ask your doctor before changing your diet dramatically if you suffer from fluid retention.
Foods High in Simple Sugars
Carbohydrates comprise over 50 percent or more of the average American diet, according to the Centers for Disease Control and Prevention, but all carbohydrates are not the same. Complex carbohydrates such as whole grains and carbohydrates in fruits and vegetables don't appear to have the same effects on your body as simple sugars found in candy, snack foods, sodas and sweets. Simple sugars raise your insulin levels faster and higher than complex carbohydrates; increased insulin levels lead to fluid retention.
Carbohydrates and Insulin
When you eat carbohydrates, the pancreas releases insulin, which helps cells remove glucose from your bloodstream to use for energy. Some simple sugars cause the pancreas to release insulin very rapidly and in larger amounts than needed. These foods have a high glycemic index. The glycemic index refers to the amount of time it takes for your body to absorb glucose. Foods with a low glycemic index remain in the bloodstream longer and don't cause a sharp spike in your insulin or blood sugar levels. Fruits, although high in simple sugars, don't always have a high glycemic index, but sodas and sweets do. Over time, you may develop insulin resistance, a condition that causes the pancreas to produce extra insulin, leading to high circulating insulin levels.
Insulin and Sodium
High insulin levels in your bloodstream causes your body to retain more sodium, author and assistant professor at the UNC Eshelman School of Pharmacy Joe Graedon explains on his website, The People's Pharmacy. When you retain sodium, your kidneys also retain more fluid. Your tissues become swollen and you develop edema.
Fluid retention can increase the risk of skin breakdown, especially in the feet and legs. Skin breakdown is a common problem in diabetics. Because diabetes also damages nerves and decreases skin sensitivity, you might not realize you have an infection until it's severe. Skin breakdown in diabetes can lead to amputation. High carbohydrate intake can also raise blood pressure by increasing fluid retention, author Gary Taubes reports in his 2008 book "Good Calories, Bad Calories: Fats, Carbs, and the Controversial Science of Diet and Health."