A period of semi-starvation before surgery may one day be just what the doctor orders, if an experiment in rats is borne out by studies in people.
Removing protein from their diet for about a week dramatically protected rats from damage to kidneys and livers when blood flow was temporarily cut off from those organs, according to a study published Wednesday. That insult is similar to what occurs during a stroke and heart attack, or what can happen to organs during long and complicated operations.
Restricting protein, but not sugar or fat, appears to kick in an ancient evolutionary response with many consequences, one of them a quelling of inflammation.
“What’s surprising is that you can do it for a really short period of time and still get a benefit,” said James Mitchell, a researcher at the Harvard School of Public Health who led the experiment, reported in Science Translational Medicine.
The study is the latest evidence that when it comes to food and health, less is often more, at least up to a point.
“I think it’s very exciting. I think it will be very interesting to see how quickly and effectively it can be applied to patients,” said Valter Longo, a molecular geneticist at the University of Southern California who is doing other, unrelated research on the effects of dietary restriction.
Reducing food intake can double the life span of yeast cells and primitive worms, and increase the longevity of mice by one-third. In people, dietary restriction has many beneficial effects, including reduced cholesterol and blood pressure.
A 2008 study by Longo and his collaborators showed that short-term starvation protected mice against the damage of high-dose chemotherapy.
People are instructed not to eat the day of surgery, but that’s simply so their stomachs are empty and the risk of vomiting is reduced.
The notion that food restriction lasting days might be helpful goes against nearly everything that surgeons are taught.
The new research does not overthrow the belief that people who are well-nourished are the best candidates for surgery. Its authors note dryly: “Our studies were performed in young, healthy rodents; it will be necessary to determine whether this approach will work when needed most, such as in elderly or obese individuals.”
