According to recent research, low carbohydrate diets such as the Atkins Diet and the South Beach Diet can affect your laboratory test results. If you are on a low carb diet and are having laboratory tests performed, you should make sure to tell your health care provider.
At this time, there have been very few large studies examining the impact of low carbohydrate diets on people’s health. However, findings from a variety of smaller studies indicate that these diets do impact body chemistry, resulting in changes to lab tests such as HDL cholesterol, LDL cholesterol, and triglycerides. These might be expected as they are markers for cardiovascular health, but a more surprising finding is that low carb diets can cause changes in other assays, such as those related to kidney function.
Until there is a better understanding of the affect of low carbohydrate diets on the body, it is best to alert your doctor or laboratorian if you are on one of these diets to help them interpret any otherwise unexplained changes in your test results.
Source:
Clinical Laboratory Strategies: How Low Carbohydrate Diets May Affect Laboratory Assay Results. February 2004, Volume 9, Number 2.