Have you ever noticed that every month seems to bring a trendy new diet and yet

obesity rates continue to rise and with it a growing number of health problems.

That's why I wrote my new book How Not To Diet. Check it out at your local public

library. Welcome to the Nutrition Facts podcast. I'm your host, Dr. Michael Greger.

Today we conclude our series on fasting with a cautionary tale about intermittent fasting.

Are there any downsides to fasting every other day? For example, might going all day without eating

impaired your ability to think clearly? Surprisingly, the results are very to be

equivocal. Some studies show no measurable effects and the ones that do fail to agree on which

cognitive domains are affected. Might the fasting-feasting cycles cause eating disorder type

behavior like binging? So far, no harmful psychological effects have been found. In fact,

there may actually be some benefit. Though the studies that have put it to the test specifically

excluded those with the documented history of eating disorders for whom the effects may differ.

What about bone health? No change in bone mental density was noted after six months of alternate

day fasting, despite about 16 pounds of weight loss, which would typically result in a dip in bone

mass. There were no skeletal changes noted in the control group either, however, that lost a

similar amount of weight using continuous calorie restriction. The researchers suggest that this is

because both groups tend to be more physically active than the average obese individuals by one to

two thousand steps a day. Proponents of intermittent fasting suggest it can better protect lean body

mass, but most of the intermittent trials have employed less accurate methods of body composition

analysis, whereas the majority of continuous calorie restriction trials used vastly more accurate

technologies. So today, it's not clear if there's a difference in lean mass preservation.

Improvements in blood pressure, antriclycerides have been noted on intermittent fasting regimens,

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