Fasting Cures Diabetes? Not Exactly

Have you seen the headlines this week about research that proves fasting can cure diabetes?

Basic science research is building a wealth of knowledge about obesity and the metabolic dysfunction that results. Research in animals is providing invaluable clues for treating this disease. But let’s face it. Reporting on this research is sometimes abysmal. The recent reporting on fasting is a good example. A round of terribly misleading headlines is proclaiming that a “fasting diet could reverse diabetes and repair the pancreas.”

The catch? Those headlines describe a mouse study.

Profound Effects of Fasting

Fasting and other forms of caloric restriction can indeed have profound metabolic effects. For a vivid example, the folks at RadioLab this week described fascinating research on the impact of feast and famine. The research utilized a rich body of data from an isolated community of northern Sweden, Överkalix. The researchers found that famine could have profound, transgenerational effects on health.

Living through a famine can change the risk of diabetes and heart disease for two generations, they found. It can have a big effect on how long those generations live. The male grandchildren of a boy who lived through a famine between the ages of 9 and 12 were much less likely to have diabetes and heart disease. They lived much longer. And the reverse was true for the male grandchildren of boys who feasted on plentiful harvests at that age.

And this is just one example of the important and complex effects that fasting or famine can have.

Fasting: A Pop Nutrition Phenomenon

As for all the pop nutrition interest in fasting, it’s not yet backed by solid science. People offer up lots of tantalizing research. The effects of fasting can be big and complex. But definitive evidence is still lacking. And pitfalls can cause serious problems. So these sensational headlines are definitely overblown.

Click here for the mouse study of fasting in Cell and here for the report from RadioLab. For the Överkalix study, click here. And click here for a review of the evidence on fasting and diabetes in humans.

Empty, photograph © Nena B. / flickr

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February 28, 2016

One Response to “Fasting Cures Diabetes? Not Exactly”

  1. February 28, 2017 at 8:08 am, David Brown said:

    “Can epigenetic changes be permanent? Possibly, but it’s important to remember that epigenetics isn’t evolution. It doesn’t change DNA. Epigenetic changes represent a biological response to an environmental stressor. That response can be inherited through many generations via epigenetic marks, but if you remove the environmental pressure, the epigenetic marks will eventually fade, and the DNA code will–over time–begin to revert to its original programming. That’s the current thinking, anyway: that only natural selection causes permanent genetic change.” http://content.time.com/time/subscriber/article/0,33009,1952313-4,00.html

    In an earlier era scientists observed changes in form and function that were passed on through several generations.

    “THE TERM dauermodifications (original German: dauermodificationen) seems to have been first used by V. Jollos in 1913. (9) It has still not found its way into evolutionary literature in general, because the climate of opinion is not sufficiently favourable toward the concept for which it stands. Yet the phenomena which it was coined to define have been observed and demonstrated experimentally for many years. Dauermodifications are the kind of modifications which are observed in living things in response to environmental pressures and which, when they occur in one generation, appear to be inherited by the next.
    Jollos originated the term to describe what he observed to be long-lasting changes induced in paramecia by heat treatment and by various chemicals, which he was persuaded were being transmitted through the cytoplasm rather than the nucleus. Moreover, he noted that such induced changes, or “modifications,” continued to be propagated over successive generations even after the inducing agent had been removed.” http://custance.org/Library/Volume8/Part_IV/chapter2.html