The End of Diabetes: The Eat to Live Plan to Prevent and Reverse Diabetes

We’ve now known for almost a year and a half that COVID-19 can cause diabetes. But how?

It’s a medical mystery that scientists are still working hard to unwrap. And at the same time as vaccination presumably confers some protection against this strange and serious side effect, the problem remains important, especially with a potentially more-infectious new variant spreading and another wave of contamination cresting across much of the United States and Europe.

In the latest issue of Diabetes Care, the American Diabetes Association’s research journal, an international constellation of specialists has patiently explained what we do and don’t realize about this phenomenon. Here’s a summary:

How COVID-19 Causes Diabetes

It’s impossible to identify the exact mechanisms by which COVID-19 appears to cause diabetes, but the experts have focused on four major factors:

Source: Diabetes Care

Beta-Cell Dysfunction: The Coronavirus’ Direct Attack on the Pancreas

The novel coronavirus that causes COVID-19 latches directly onto the pancreas. Its primary mode of attack is through the body’s ACE2 receptors, proteins that are found in great concentration on the pancreatic islet cells, among them the extremely cells that produce insulin. The failure of those cells is characteristic of both major types of diabetes.

The pancreas, therefore, is one of the front lines in the body’s battle against the coronavirus. It’s easy to imagine how this mechanism can elucidate the phenomenon of new-onset diabetes associated with COVID-19. However, researchers haven’t been able to confirm that this explanation is accurate; at least one experiment has indicated that the ACE2 receptors on the pancreas are unlikely to explain new-onset diabetes.

COVID-19 also harms the pancreas in other ways. The contamination is often accompanied “by an aggressive inflammatory retort with the release of a immense amount of pro-inflammatory cytokines,” the infamous cytokine storm. The cytokine storm takes an especially huge toll on the pancreas and on the insulin-secreting Beta cells; autopsies of patients that died of COVID-19 showed signs of islet cell degeneration and pancreatitis.

Many diseases cause acute inflammation of the pancreas, damage that may hasten the development of both type 1 and type 2 diabetes. Sometimes, when viral infections are intense and serious enough to cause immediate permanent damage to the pancreas, it results in a form of diabetes sometimes referred to as type 3c diabetes. It has also been long-suspected that an unidentified viral infection may trigger some or all cases of type 1 diabetes.

Stress Hyperglycemia

Patients with diabetes already be aware of that stress and disorder can send blood sugars skyrocketing. The same thing can happen with healthy patients, too, who often have “stress hyperglycemia” during severe infections and other illnesses.

Serious COVID-19 infections trigger a huge and very complex response in the body. The damage wrought by the disease and the body’s immune response can both temporarily cause inflammation and spike insulin resistance. It’s a dangerous situation: patients with more acute hyperglycemia are more likely to die or suffer other severe outcomes.

While these effects aren’t unfamiliar to doctors (and about a decade ago, the SARS coronavirus pandemic also triggered “acute diabetes”), it appears that COVID-19 causes much more stress hyperglycemia than other illnesses. A huge number of patients that have never before had blood sugar issues in their life find themselves suddenly requiring insulin and glucose-lowering medications.

Stress hyperglycemia can be temporary – but a learn about in India found that months after beating COVID, about 20% of patients that had experienced stress hyperglycemia were still struggling with blood glucose control and were diagnosed with diabetes.

Steroid Use

It is well-known in the medical community that steroids can cause hyperglycemia. A meta-analysis conducted years before the pandemic found that heavy use of glucocorticoids can actually induce diabetes at a terrifyingly high rate (18.6%). The steroids used to fight COVID-19 are no exception – the authors of the recent Diabetes Care article suggested that “steroid-induced abnormalities” can exacerbate the Beta-cell damage caused by COVID-19 by delaying or impeding the body’s ability to repair the damage.

Preexisting Undiagnosed Diabetes

Then again, sometimes COVID-19 and new-onset diabetes have nothing to do with each other, even if they’re diagnosed around the same time. Some cases of new-onset diabetes would have occurred with or without the coronavirus.

The CDC reports that a whopping 7.3 million American adults have diabetes but have never been diagnosed with the condition; this represents an astonishing 2.8% of the country’s adults. In adults over the age of 65 – those most likely to require hospitalization for COVID-19 – the CDC estimates more than 5% have undiagnosed diabetes.

Since the beginning of the pandemic, over 3 million American patients have been hospitalized with COVID-19. If most of them had their blood sugar evaluated, we might expect that tens of thousands might have learned, for the first time, that they had diabetes.

Our experts also speculate that lifestyle changes triggered by lockdowns – weight gain, lack of exercise, social isolation – could have pushed even more adults towards diabetes than normal in 2020 and 2021.

Does COVID-19 Cause Type 1 Diabetes, or Type 2, or Something Else Entirely?

Nobody can really say for sure.

You can imagine how intense and complex the symptoms are in patients that show up at the hospital with both COVID-19 and new-onset diabetes. There isn’t much opportunity to isolate exactly what is happening and why.

Multiple reports do say that new-onset diabetes associated with COVID-19 most resembles type 1 diabetes, that is, a dangerous and potentially lethal lack of insulin due to Beta-cell failure in the pancreas. Some of these patients develop diabetic ketoacidosis (DKA).

But is it really type 1 diabetes if the Beta-cell destruction is caused by COVID-19 infection, and not an autoimmunity condition? That’s a question for experts to debate in the future.

Given that acute infections are known to hasten the development of type 1 and type 2, in addition to causing type 3c, it’s possible that the coronavirus is doing all 3.

Is New-Onset Diabetes Associated with COVID-19 Permanent?

There is frustratingly little good evidence on this critical question. We know that many patients with acute hyperglycemia during COVID-19 make full recoveries. The number of patients that have apparently been afflicted with permanent diabetes is completely unknown. If anyone has good data on the long-term outcomes of patients that were diagnosed with new-onset diabetes associated with a COVID-19 infection, it hasn’t been released publicly yet.

The evidence we do have is meager. And all analysis is furthermore confused by “long COVID,” which is believed to affect many different health aspects for months after recovery.

A case series from India, for one, followed three patients that presented with both COVID-19 and hyperglycemia so severe that they were in DKA. All three were eventually able to discontinue insulin treatment, suggesting that the Beta-cells rebounded robustly and that they did not contract full-blown type 1 diabetes. At the time of writing, however, they remained on oral glucose-lowering medication.

The earlier study from India mentioned above found that about 20% of patients that were diagnosed with diabetes in the hospital with COVID-19 still had diabetes several months later.

We also know that a surprising number of COVID-19 patients are diagnosed with diabetes after they have recovered from their illness. Studies in China and in England found that 3.3% and 4.9% of patients developed diabetes in the months after their recovery from COVID-19.

These results recommend that the infection can cause lasting metabolic damage that emerges only after apparent recovery. The Diabetes Care authors believe that it might be worthwhile to screen everyone that’s been diagnosed with COVID-19 for diabetes and prediabetes, and possibly monitor for cardiovascular and kidney complications too.

Much more study is needed on this topic; researchers are still only scratching the surface. As the pandemic continues to rage on, we can expect more updates.

Diabetes Daily

The End of Diabetes: The Eat to Live Plan to Prevent and Reverse Diabetes