Scientists Debate the Safety and Efficacy of Fasting

Over the course of the last several decades, the public health consensus has been that fasting -- that is, going hours or days without food or other forms of nourishment -- is an unsafe practice that has no place in a healthy lifestyle. In fact, individuals who regularly engage in fasting have often been categorized as displaying disordered eating patterns.

However, historians and anthropologists tell us that humans have been fasting for thousands of years. Periods of abstinence from food are part of every major world religion, and the archaeological record suggests that these rituals date back into the time of our prehistoric ancestors.

A small group of scientists have begun to argue that today's "three square meals" mindset is probably a far cry from the on-again, off-again, feast-or-famine lifestyle that our prehistoric ancestors led. Taking a cue from this line of research, some groups of health-conscious mavericks have begun to implement periods of fasting as part of their regimen for weight loss and/or maintaining a healthy body weight.

This week, we'll dive into the thick of the ongoing scientific debate over the health and safety of fasting, taking a look at the result of three different studies that have tackled aspects of this controversy.

Study Suggests that Alternate-Day Fasting May Shrink Fat Cells

The idea of going completely without food makes most people uncomfortable. However, the findings of one recent study suggest that a partial fast every other day may deliver the same satisfying weight loss results as unbroken fasts.

The study, which was published in a recent issue of the journal of the American Society for Biochemistry and Molecular Biology, compared the effects of unbroken and alternate-day fasting in male mice. The mice that fasted every other day showed several specific results that may have positive implications for those seeking to lose weight or maintain a healthy body weight.

The alternate-day fasters lost fat under the skin, but not the special type of fat that is often found to be concentrated around the abdomen. Also, the alternate-day fasters appeared to have a measure of protection against long-term obesity and the development of Type II diabetes. Although there were some indications that the alternate-day fasting might help protect against other diseases, the researchers cautioned that further investigation in this area is necessary before firm conclusions can be drawn.

Restricted-Calorie Fasting May Reduce Obesity, Increase Life Span

Throughout the twentieth century, research demonstrated that mice who were fed very low-calorie diets often outlived their counterparts who were fed "normal" diets. However, the true significance of these findings remained unclear for decades.

In recent years, the connection between restricted-calorie diets, health, and longevity has begun to be further explored. One study conducted by researchers at the Salk Institute for Biological Studies pinpointed a genetic cause for this relationship.

The scientists used studies of a particular type of worm to unravel the complex relationship between calorie restriction and longevity. Specifically, the researchers identified the missing link in the relationship as glucagon, a pancreatic hormone that heightens the concentration of the blood sugar and helps to maintain the body's balance of energy.

When calories are restricted to 60% of the normal level, the genetic controls that oversee glucagon balance appear to be activated. However, the scientists underscore the importance of a balanced, vitamin-and-mineral rich diet in any attempt to restrict calories to longevity-boosting levels.

Hunger Response during Fasting More Complicated than Previously Thought

It seems obvious that going without food for an extended period of time causes hunger. But the body's response to sustained periods of fasting is much more complex than that. According to a study conducted by scientists at the Mount Sinai School of Medicine, the neurological chain of events that regulate the experience of hunger during fasting involves an interaction between three hormones, two cell types, and a specific type of protein.

By identifying the precise sequence of reactions that cause and sustain the sense of hunger during fasting, the researchers have cracked part of the neurological code of the hunger response. In time, this could lead to the development of pharmaceutical treatments that could ease the pain of hunger during restricted-calorie diets designed to help patients overcome obesity.

Before incorporating fasting into your weight-loss regimen, consult with your physician or a licensed nutritionist. Check this space each week for the diet research news you need to make your weight loss journey a success.