Although I covered the health effects of intermittent fasting (IF) in the October 2015 issue of Applied Metabolics, new information has been recently published about IF that is highly relevant to those who seek both body fat loss and added muscular mass. In my previous article, I pointed out how studies show that IF can replicate most of the health effects produced by a calorie-restricted diet. The typical calorie-restricted diet used for purposes of extending longevity and various health parameters, such as lowered blood lipids (fats), lower blood pressure, and lower resting insulin levels, usually involves restricting customary total caloric intake by an average of 30 percent. Studies in various species ranging from worms to mammals show that reducing total caloric intake to this level appears to reduce or even block many of the degenerative health changes that commonly occur with aging. Indeed, lowering calories to this extent may even preserve muscle tissue, although due to the extent of decreased protein intake on such diets some muscle is inevitably initially lost. A more recent analysis of calorie-restriction regimes suggests that even if followed for extended times will only produce an average 10-year boost in lifespan. But reducing behaviors are known to be toxic, such as smoking and drinking excess alcohol, as well as regularly engaging in both resistance training and aerobic exercise can also boost lifespan by about the same amount, minus the rigorous food restriction. Indeed, the aspect of calorie-restricted diets that seems to improve health and longevity is that it leads to the loss of considerable body fat, an effect that can also be achieved by exercise and more realistic eating regimes. Studies show that most people cannot tolerate consuming a diet that features 30% less than customary caloric intake. These studies show that the least caloric reduction level tolerable to most people was to reduce total caloric intake by 15 percent.
But there is another option that may allow you to reap the considerable benefits of calorie restriction in a far more tolerable manner. This involves intermittent fasting techniques. I use the plural "techniques," because the term intermittent fasting (IF) is a general term since there are several varieties available. Three main versions of IM exist: 1) Alternate-day fasting, which as the term implies features eating normally one day, following by fasting the next day. The fasting days usually involve not a complete lack of food intake, but rather eating only one meal that contains about 25% of daily caloric needs or intake. 2) Whole Day fasting involves fasting one or two days a week, eating normally the rest of the week. 3) Time-restricted feeding (TRF) features eating the same way every day, but you only consume food within a specified time frame, and fast the rest of the time. This would mean something like 16-20 hours of fasting, followed . . .