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There Are Some Medical Situations Where Being Overweight Could Help Save Your Life

Researchers are calling it the "obesity paradox".

MIKE MCRAE
25 MAY 2018
 

It may sound strange at first, but having excess body fat could help to reduce your chances of succumbing to an infectious disease in hospital.

For the many health problems a high body mass index (BMI) can cause, there's a heated debate over whether obesity can ever be a good thing. And a number of recent studies provide evidence to support the view that there can be medical benefits to having 'too much' weight.

 

Research led by Aarhus University Hospital Department of Clinical Epidemiology in Denmark has concluded that obese patients admitted into hospital for an infectious disease were 50 percent less likely to die after being released than those of normal weight.

In contrast, being underweight more than doubled the risk of passing away within just a few months of being discharged.

Presenting at this year's European Congress on Obesity in Vienna, Austria, the research team explained how they analysed the medical records of more than 18,000 hospital inpatients in Denmark between 2011 and 2015.

"Overweight and obesity were associated with substantially reduced 90-day mortality following incident hospital admission for infection," the researchers state.

"An association between underweight and increased mortality was confined to patients with recent weight loss, suggesting confounding by other hidden disease."

Whether or not you're surprised by the results, the results add fuel to a debate that's been raging since 2003 over whether obesity helps certain categories of people stay alive.

There's little argument that as body fat weight accumulates, chances of suffering a debilitating and deadly condition increase. If we go by BMI alone, larger index scores put a person at greater risk of anything from Type 2 diabetes to heart disease to various cancers.

 

But there's a lot of nuance when it comes to people who are overweight. Not all body shapes and sizes are exposed to the same level of risk.

Masked by those general statistics of the overall population there are sub-categories where having more visceral fat surrounding your gut's organs is found to be worse than just having a thick layer of adipose tissue under your skin.

Two people with the same BMI don't actually face the exact same chance of health problems. So pulling apart the figures to identify precisely how and when fat confers a specific risk suggests the obesity problem can be more complicated than first appears.

Is it possible that when it comes to some people, excess mass lends a helping hand in the face of an even greater threat?

Enter the obesity paradox: 15 years ago, researchers from the UCLA School of Medicine published a report arguing obesity could actually help protect patients with chronic kidney disease from suffering certain complications.

There was no simple mechanism explaining it, and even as other studies started to crop up showing similar results with other health conditions, the question remained whether it was an accurate reflection of the benefits of obesity or a statistical artefact.

 

One possibility is the impact of weight gain stirs the immune system into a ready state of action. Another is that it offers a kind of an energy reserve.

On the other hand, it could also just reflect a bias in the way data is collected; a blip caused by experimental factors we can't seem to iron out.

The paradox of 'healthy' obesity continues to be a point of contention in the medical field, with experts debunking and supporting the hypothesis with regularity.

While there are plenty of reasons to question the research, those supporting studies do appear to be piling up.

A second study presented at the European Congress on Obesity found obese patients were up to 30 percent less likely to die from lung infections. Analysing more than 1.7 million cases of pneumonia in over 1000 US hospitals, the researchers found an "increase in body mass index was significantly associated with improved survival."

Yet another piece of research presented at the meeting compared the ways bodies of different BMIs catabolised - or broke down - body tissue when under physical duress.

 

The timing and distribution of deterioration was clearly different in obese patients when comparing the effects of blood poisoning and brain trauma, hinting at explanations of why 'too much' body fat could sometimes be 'the right amount'.

"Critically ill patients with obesity seem to have higher muscle quality," state the researchers from Erasmus MC University Medical Center, Rotterdam.

"This might be the metabolic protective shield also described as the 'obesity paradox'."

If such a metabolic protective shield is indeed genuine, nobody is suggesting we should all break out the doughnuts and bin our running shoes to build up a handy energy reserve of belly fat.

Statistically speaking, we're all better off doing what we can to limit our weight gain and keep our spare tyre to a minimum.

But knowing exactly how our bodies makes use of our fat tissue in times of need could offer solutions that help increase our chances of surviving illness.

The latest results were presented at the 2018 European Congress on Obesity.

 

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