Several studies have reported that low-carb diets increase the risk of mortality (shorten lifespan).  However, two studies published a few years ago have come to the opposite conclusion.  Those studies have low-carb enthusiasts claiming it is time to rewrite nutritional guidelines to favor low-carb diets.  
  However, a study published a year later resolves the conflicting data and finally answers the question: "How much carbohydrate should we be eating if we desire a long and healthy life?"  The answer is "Enough".  According to this study, high carbohydrate intake is unhealthy. Low carbohydrate intake is unhealthy.  But moderate carbohydrate intake is "just right".

Specifically, this study reported: 1) Moderate carbohydrate intake (50-55%) is healthiest.  This is also the carbohydrate intake recommended by current nutritional guidelines.  2) All major studies agree that very high carbohydrate intake (60-70%) is unhealthy.  It shortens life expectancy of a 50-year-old by about a year.  3) All studies that cover the full range of carbohydrate intake agree that low carbohydrate intake (<40%) is also unhealthy.  It shortens life expectancy of a 50-year-old by about 4 years.  4) The studies quoted by low carb enthusiasts to support their claim that low-carb diets are healthy don't include carbohydrate intakes below 40%.  That means their claims are misleading.  The studies they quote are incapable of detecting the risks of low carbohydrate diets. 5) Meat-based low-carb diets decrease life expectancy while plant-based low carb diets increase life expectancy.  This is consistent with the results of previous studies.  Animal-based low-carb diets should be discouraged.
  When restricting carbohydrate intake, replacement of carbohydrates with predominantly plant-based fats and proteins could be considered as a long-term approach to healthy aging. ~ Mary Ann 

Next week: Recovering from a Meniscus Tear.