Low carbohydrate diets (LCD) may help body weight loss and glycemic control in diabetes but their long-term consequences are not known. The aim of this review is to highlight the contrast between the potential benefits of short term LCD and the adverse health effects of long-term consumption of LCD. LCD can enhance weight loss in the short term although its effect is small and not sustainable. In people with diabetes and insulin resistance, LCD is helpful in achieving glycemic control. However, there are untoward side effects especially when carbohydrates are severely restricted (< 50 gm a day) to induce ketosis. The latter curbs appetite but also may cause nausea, fatigue water and electrolyte losses and limits exercise capacity. In addition, observational studies suggest that low carbohydrate diets (< 40% energy form carbohydrates) as well as very high carbohydrate diets (> 70% energy from carbohydrate) are associated with increased mortality. The available scientific evidence supports the current dietary recommendations to replace highly processed carbohydrates with unprocessed carbohydrates as well as limiting added sugars in the diet.
Keywords: Low carbohydrate; high protein; ketosis; weight loss.