For most of the past decade, there was much hubbub about the Atkins and Zone diets. Both focus on quick, effective ways to lose weight through high-protein and low-carbohydrate foods. Today, many still swear by them. However, research on these diets has been very limited. A group of scientists who have been studying the diets since 2005, now report finding many biomarkers being negatively affected by the severely low-carbohydrate intake.