Refeeding Syndrome and Sudden Death

by Brian Dunning
April 23, 2019

We've all seen it in the newsreels: Europe, 1945, Allied forces liberating the prisoners in the Nazi concentration camps. Shocked at the skeletal condition of some of the prisoners, who have been subsisting on starvation diets for months or even years, the soldiers hand over every scrap of food they can lay their hands on. But then — many of these reports say — the succor has an unexpected and horrifying effect: some of the prisoners fall instantly dead at the first bite; within minutes many others have followed. Today we're going to look at the facts behind stories of starved people suddenly dying upon receiving their first bites of food.

The most infamous of these stories comes from the Bergen-Belsen concentration camp in northern Germany, best known as the camp where Anne Frank died after her family's arrest. Belsen did not have gas chambers and did not conduct mass executions as were done at Auschwitz and others, but by the end of the war it was suffering from a terrible epidemic of typhus and was as deadly as any camp. In December 1944, five months before the camp was liberated, Germany began mass transportation of prisoners from other camps into Belsen. This made the overcrowded, diseased, and starvation conditions far worse. From that point, the death rate of prisoners approximately tripled every month, reaching over 18,000 dying in March 1945 alone.

When the allied troops arrived, they found 60,000 survivors, most of whom were near death from either typhus, starvation, or both. From an article about Belsen in a BBC series on the liberation of the camps:

Some inmates had been starved for so long that they had lost the ability to digest the rations that well-meaning British soldiers offered them; within minutes of taking a biscuit, some inmates just passed away.

One British doctor told the Imperial War Museums how they attempted to help:

The food that we'd got, breaking open these compo rations was just not right for these people — their stomachs just couldn't take anything. The best we could do was... make it a thin stew... Some people who tried to eat the real stuff straight away, I'm afraid it was too much and they, it probably killed them. But it was kindness to give them something, although it is the wrong kind of kindness.

The emergency response effort was massive, but receiving 60,000 critical patients all at once is a pretty tall order. 14,000 of the newly-liberated prisoners died after their liberation. The rate was even worse at other camps. From the Holocaust Encyclopedia:

Allied troops, physicians, and relief workers tried to provide nourishment for the surviving prisoners, but many of them were too weak to digest food and could not be saved. In spite of the liberators' efforts, many camp survivors died. Half of the prisoners discovered alive in Auschwitz died within a few days of being freed.

Although there are anecdotal accounts of prisoners dying within seconds of their first food, reports of such super-fast deaths are absent from most of the literature. Reports of slower deaths occurring within a few days following the resumption of food intake are, however, commonly found in reliable histories.

Are these stories medically plausible? The answer is largely a resounding yes, with an exception for claims of sudden deaths. What happens in cases like these is a potentially fatal medical condition called refeeding syndrome, where changes in body chemistry can trigger any of several causes of death. For centuries there has been a vague general knowledge that bad things can happen when we suddenly start feeding starving people, but it wasn't until World War II and all of its many cases of starvation around the world that science began to take a serious look at what was happening.

In the references below are links to a number of articles that explain the biochemistry behind refeeding syndrome in full detail, but I'll just give the abbreviated version here. Your body makes a number of changes to its chemistry in response to starvation, changes which are intended to preserve its most important tissues for as long as possible. Electrolyte imbalances often result. Then when you start eating again, a whole wave of fluid and electrolyte shifts takes place. Insulin production increases, among other changes. The main feature of refeeding syndrome is hypophosphatemia, a dangerous shortage of phosphates in the serum, as well as shortages of other minerals. Phosphorus in particular is essential for all cellular processes, and hypophosphatemia can result in respiratory failure, cardiac failure, arrhythmia, seizures, coma, and death.

Although the liberating soldiers at Belsen quickly learned that refeeding was doing its share of harm, the mechanisms weren't known. But they couldn't just not feed the people. And from what's recorded historically and what's known today, it does indeed appear that fatal refeeding syndrome was responsible for at least some substantial portion of those 14,000 post-liberation deaths.

We do see refeeding syndrome today. There's no ethical way to deliberately put test subjects into such a dangerous physical state, but people already in that condition do come into hospitals so we do have study data on the syndrome. Mostly these are anorexia nervosa patients, but there are a variety of other types of patients with severe malnutrition. Among other lessons, these cases have given us an opportunity to study the actual time of onset of hypophosphatemia. The mean time is 1.9 days after refeeding begins. This is generally in line with the best reports from Belsen and other camps, which stated that many prisoners died after just a few days. It does not support the anecdotes claiming that people died instantly or within minutes of downing a tin of bully beef gifted by a concerned soldier.

More importantly, these modern cases have taught us how to refeed safely and avoid the syndrome altogether. According to data published in the British Medical Journal which studied over ten thousand such cases, 100% of patients went into hypophosphatemia when fed intravenously with a solution that did not include phosphorus supplementation; but when it did, the incidence was reduced to just 18%. So clearly, phosphate supplementation is key in refeeding. The currently recommended guidelines for refeeding malnourished patients is to start with multivitamin supplements, and then proceed with feeding at 10 kcal per kilogram of body weight per day, and slowly increase it over four to seven days. If the patient is severely malnourished, or has not eaten at all for two weeks, then refeed beginning at 5 kcal per kilogram per day. An adult man at Belsen would have weighed about 45 kg (or 100 pounds), so they should have been given about 225 kcal a day to start with. Constant rehydration with supplementation of potassium, phosphate, calcium, and magnesium, as well as frequent monitoring of serum levels of these minerals, is essential. Sadly, in 1945 we didn't yet have this knowledge, but we were trying to figure it out.

Towards the end of World War II, knowledge of the Nazi concentration camps had begun to spread, and there had already been cases of prisoner-of-war camps around the world where prisoners had suffered severe starvation. So in 1944, the United States launched a study to learn more about the effects of starvation and how best to recover from it. It's now known as the Minnesota Starvation Experiment. Its principal investigator was Ancel Keys, the eminent physiologist who pioneered so much dietary research throughout the twentieth century. He is perhaps best known for his Seven Countries Study, which ran for 50 years and established the connections between dietary cholesterol and heart disease.

The Minnesota experiment drew its volunteers from the ranks of conscientious objectors, men who had been drafted for World War II but refused to fight, and so had been assigned to the Civilian Public Service where they could escape prosecution by performing domestic work considered to be of national importance. From hundreds of volunteers, Keys selected 36 subjects. For six months, their diets were cut to 1,560 kcal/day, mainly of potatoes, rutabagas, turnips, bread and macaroni to simulate what Europeans had to eat in the latter stages of the war — and by the end of those six months, they were looking pretty skeletal. Finally they were re-fed in various different controlled groups over three months.

While Keys' experiment had potential to help the concentration camp prisoners, it didn't help much. First of all, its results came too late. Second, it was designed more to simulate the experience of ordinary European citizens whose deprivation was caused by wartime shortages, not of concentration camp prisoners whose deprivation was far more severe. When Keys' subjects began their refeeding at the end of the six months, they had been on a diet that, while restrictive, was still somewhat nutritious; so they weren't sufficiently malnourished for refeeding to trigger hypophosphatemia like so many of the Belsen prisoners.

Another point that seems clear is that death from refeeding syndrome doesn't seem to have anything to do with an inability to digest the food. That appears to have been just the best guess made at the time by the witnesses, and it made it into most of the written histories and is still the most common explanation repeated today.

There's one other question that I found frequently asked on this subject, and it's whether some of those anecdotal instant deaths — like the one in the BBC article — might have been from one of the co-morbid conditions — most camps had disease outbreaks; Bergen-Belsen alone was raging with typhus, typhoid fever, dysentery, and tuberculosis. One of the most detailed histories of the liberation of Belsen is the massive German language 9-volume set Place of Terror: The History of Nazi Concentration Camps. According to the authors of Volume 7 which includes Belsen, the sheer scope of the incident for the Allied medical services was so overwhelming that it became impractical to keep good records of the causes of so many deaths. Camps liberated by the Soviets had no records at all. So we can't offer a good answer to the question of whether the fast deaths were the result of refeeding syndrome or of one of the other diseases, but it is noteworthy that none of those other diseases are consistent with a sudden death from eating a biscuit.

A final thought. As an example for the subject of refeeding syndrome, this episode brought up the Holocaust. Obviously that's a topic of infinitely greater importance which touches many more aspects of society and culture than just this one bit. In remembrance of the countless people whose actual lives lost we used today, I suggest making it a priority to visit any Holocaust museum or memorial at your next opportunity, especially those of you who have never been to one before. If everyone would make such a visit, the world would be a better place. It happened, and it can happen again.

By Brian Dunning
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