Hacker News Reader

Comment by fragsworth | Hacker News Reader

No. One virus made chickens subjected to the virus gain weight when compared to the control group, even though they were fed the same amount. That virus actually very directly causes obesity, and the claim is that there are similar viruses in humans, which we've found correlational data for, but we can't ethically test for it.

View on HN

Technically, the virus directly causes overeating, not obesity, the title makes it sound like this virus could make you gain more weight for a different reason.

"Cause Obesity" sounds like it is the entire reason behind all of obesity, not just one of the multiple factors.

The article specifically mentions the guy lost minimal weight even during medical interventions when his diet was restricted. He wasnt overeating during those periods.

The article was a bit confusing on the relationship between food, blood work and other health aspects. Diabetes later in life - lack of insulin does not necessarily lead to weight gain - insulin is encouraging cells to store energy after all. Low triglycerides may be result of low fructose diet.

As the weight gain effect can be reproduced in animals I wonder whether there is more animal blood and cell data that could provide clues on the underlying mechanism. I can't imaging they only used a scale to measure the outcome but then the proof is in the pudding.

Well, I don't think implying diabetes (type 2) is a lack of insulin is entirely accurate. The problem is insulin resistance in cells, because they're saturated with insulin, where they mostly stop responding to insulin. Which then results in the pancreas not being able to produce enough insulin to lower blood glucose. It's like a deaf person saying the music isn't loud enough -- the volume is fine, their ears are just shot. You can make the music louder (inject insulin), but their ears will just get worse. When you have that much insulin in your system though, you're definitely not losing weight -- because the cells are saturated with insulin they're definitely not in fat burning mode.

But you clearly cannot eat at a deficit and gain weight. A virus cannot directly make you gain mass.

The energy can be used in a variety of ways. So yes, of course the same exact caloric intake can have different effects, depending on what exactly your body does with the energy.

No, but a virus could change your appetite, your body's allocation of energy from lean mass to fat mass, or alter your overall metabolism. Or any combination of those.

> But you clearly cannot eat at a deficit and gain weight.

This is just question-begging. The proposed mechanism is that the virus alters what a deficit is.

And I think that's a very distinctly different thing from "directly causes obesity".

When people say "directly causes obesity", they don't mean it's a magic spell that reverses thermodynamics. Something that stops a large amount of calories from being burned and turns them into fat reserves deserves the title of "directly causes obesity".

So why aren't people in hot countries all obese?

Why would they be? Human metabolism evolved for hot climate after all. So, the body can regulate itself. Unless it's infected by a virus, which alters this regulation. And, unlike you imply, living in a hot country does not shift your energy usage towards fat creation like the virus does.

In the same way that a lit match tossed into a building doesn't "directly cause a fire" because it's actually a series of chemical reactions that cause the fire, I suppose that's correct.

> But you clearly cannot eat at a deficit and gain weight.

You can't without limit, obviously, but since muscle has a much lower per-pound energy content than fat, it's quite possible to eat at a deficit and gain weight while decreasing body fat %.

But, more to the point, a virus can affect, what and how much you are inclined to eat, how efficiently or not your body absorbs nutrients, and a number of other factors which influence whether or not you experience a deficit in the first place.

You're mistaking weight for density.

You can't create mass out of nowhere. If you transform fat into muscle, you still have the same amount of the same atoms, and thus weight the same.

> You're mistaking weight for density

No, I'm not.

> You can't create mass out of nowhere.

Calories measure energy content, not mass.

> If you transform fat into muscle, you still have the same amount of the same atoms

No, you don't.

> and thus weight the same.

Yes, if you trade one pound of fat for one pound of muscle, weight is the same. But since fat has an energy content around 3500kcal/pound and muscle is, IIRC, around 750kcal/pound, that corresponds to more than a 2500kcal calorie deficit with no weight change.

> it's quite possible to eat at a deficit and gain weight

> since fat has an energy content around 3500kcal/pound and muscle is, IIRC, around 750kcal/pound, that corresponds to more than a 2500kcal calorie deficit with no weight change

Feel free to ask a friend with chemistry or physics background why this is completely wrong and goes against everything we know about matter and energy.

Like others mentioned, your body can allocate energy in a variety of ways depending on hormones. If you're at a caloric deficit, your body can do things like: reduce heat production, reduce energy available for activities, reduce metabolism, reduce production of proteins for hair/fingernails, etc. There's no hard requirement it burns fat. That's what healthy bodies do of course, but metabolic syndrome is where that entire system doesn't work.

This is not a topic I'm an expert on, I was originally just annoyed with the way the article title was worded, but those claims seem pretty wild. Do you have anything to back those up?

> reduce heat production

Then what? It only takes a few hundred kcals of lesser heat production to reduce an adult body a few degrees, which would cause severe hypothermia.

> there's no hard requirement it burns fat

To what extent? Are you saying he would die of starvation before losing significant weight?

Reply on news.ycombinator.com