Why do older people lose so much weight as they age?

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This question was prompted by seeing photos of Gene Hackman in the other thread, who at 94, looks incredibly thin relative to when he was acting. Another actor who this has happened to as well is Clint Eastwood, who is 93. Starting with "The Mule", when he was 88, he looks to have lost a ton of weight, which accelerated even further when he did "Cry Macho" when he was 91 in 2021. I'm wondering why this seems to be common. Illnesses like cancer can cause weight loss, but it appears to happen in people who don't have cancer and to be too common to be entirely a symptom of major chronic disease. There's no evidence either Eastwood or Hackman does have cancer, for example. It seems to be a result of aging, but I genuinely am interested in the potential causes for why. What is it about aging, when someone gets into their 80's for example, that appears to cause people to lose a lot of weight?



I'll play Yoda and say that the idea that they do might be cherry-picked. Hackman and Eastwood did. How many old people didn't?
__________________
Preserving the sanctity of cinema. Subtitles preferred, mainstream dismissed, and always in search of yet another film you have never heard of. I speak fluent French New Wave.



I see it's time for another round of "no, please, let me Google that for you"


Weight loss is something many adults strive for. Most of us have looked in the mirror at some point and figured we could stand to lose a few pounds. Your doctor may have instructed you to lose weight for your health. But as we age, some of us might find that weíre losing weight without meaning to.

Unintentional weight loss is a common issue in older adults. While there can be medical factors involved, thereís often no explanation for the pounds that simply slip away. About 25% of patients who are older adults experience unexplained weight loss of some kind.

Weight Loss as You Age: Whatís Normal and Whatís Not?
Normal weight loss. As you get older, you start to lose lean body mass like muscle and bone density. As early as age 30, our lean body mass starts to drop by a little over half a pound each year. You might not notice a change when you step on the scale, because the lean weight you lost is often replaced by fat.

Men vs. women. Weight loss can be different for men and women. Men tend to gain weight until age 55, and then slowly start to lose it in the years that follow. This could be because men produce less testosterone after this age. Women, on the other hand, usually stop gaining weight once they hit age 65.

Abnormal Weight Loss. After the age of 65, itís typically normal to lose 0.2 to 0.4 pounds of body weight every year. Unintentional weight loss can be dangerous if you lose 5% or more of your body weight every 6-12 months.

What Causes Weight Loss as You Age?
Reasons for weight loss. Many factors can contribute to your clothes fitting a little looser as you get older. Most of these are social, psychological, and medical reasons, including:

* Cancer
* Stomach or intestinal disease
* Depression
* Dementia
* Diabetes or other endocrine disorders
* Heart problems
* Alcoholism
* Kidney disease
* Side effects of medication (can include loss of appetite)
* Financial issues
* Problems with finding nutritious food or feeding oneself
* Not getting enough food (malnutrition)
* Late-life paranoia
* Dental issues
If none of these apply to you, you aren't alone. The cause of unintentional weight loss is still unknown for up to 28% of patients.
So, there you have it. Yes, it's normal to lose some weight when you get older, but "unintentional weight loss can be dangerous if you lose 5% or more of your body weight every 6-12 months."

I'm sure both Hackman and Eastwood have very good medical care available to them, so they are probably either perfectly healthy or have doctors looking at any possible medical needs.



In general, your metabolism slows.
For some (who keep their food consumption in proportion with their metabolism), this ultimately results in less hunger and less food consumed, and thus weight loss.

Simultaneously, as you age, you shrink - this is due to a combination of lessening bone density and our old friend gravity (it can kill you if you fall from a height, but without it for an extended period of time, we'd all be immobile blobs of Jell-O). The shrinking causes you to lose both height and weight.



It's not just Eastwood and Hackman. I know many older people and it is quite common for them to become thinner as they get older, so I don't think it's just a case of cherry picking. Does it happen to every elderly person, no, but it's common enough to not be a random event.

Eastwood looks like he's lost at least 40 pounds. His normal weight was around 200 pounds, give or take a few, and he looks nowhere near that now. Hackman also looks like he's lost a ton of weight. If you go by what the article states as being normal, 0.4 X 25 years, for example, if they started losing at 70, would be only a 10 pound loss, and they've both lost a huge amount more than that based on the photos, or in Eastwood's case, recent films in which he's appeared.

This article has some good information, some of which I was aware of, some of which I was not. A slowing metabolism would actually likely result in you gaining weight, rather than losing it, and loss of muscle mass wouldn't necessarily result in you losing weight, but instead, gaining more fat while remaining at, or above, your normal weight. Neither one of these explanations really address this phenomenon, in my opinion. Eating less food over the years is a possible explanation, but I don't think you lose as much weight as Eastwood and Hackman have just by eating a little bit less. It's too much weight for that.

Type II diabetes, cancer, depression, etc. can result in unexplained weight loss, that is true, but I think I was looking for causes that weren't the result of a chronic disease, since we don't know if Eastwood or Hackman has a chronic illness or not. But since Eastwood, in particular, is still able to direct movies, it's unlikely he's so debilitated that he's losing this amount of weight due to major illness, since if that were the case, he likely wouldn't be able to still direct.

The most interesting aspect of the article cited above is that in more than a quarter of cases, the cause may be unknown and not the result of anything in particular.



Over time, the slower metabolism results in less appetite, a shrinking of the stomach and weight loss.

Unless, of course, if you keep eating like when you were 18 as you move into your geriatric years, you will end up an obese elderly person. Overweight elderly people are usually compulsive eaters who eat not out of hunger, but out of life-long habit, obsession, boredom or other problems.

For most people over 70, as their metabolism slows, they eat less and less. As with any reduction diet, over time your appetite will decrease as your stomach becomes smaller. The thinner you get, the less food you need, and in most cases, the less you desire. And again, combine the slower metabolism with less calorie intake and lessening bone density and gravity shrinking you... and it's no wonder elderly people tend to lose weight (and height and mass) the older they get.



Or maybe they're both on ozempic...



Thanks for these helpful thoughts, Captain Steel. It is certainly true that everyone loses height as they age, but what is the connection between losing height and losing weight? Logically, if someone loses height as they age, their Body Mass Index and body fat percentage both go up, not down. Also, if they do not strategically lower the amount they are eating as their height declines, they'd actually gain weight, right? Is the idea that as you lose height, your caloric needs decline as well, and so this is another explanation of why people also lose weight at the same time? I'm not sure I fully get the connection here. I understand that shorter people will have lower caloric needs than taller people, so they may eat less throughout their lives, or at least they should, but height is a relatively stable characteristic for adults. I'm not sure that if someone who was 6'2 becomes 6 foot over 10 years as they age that they then eat as if they were shorter than they've been their whole lives. Do they not act like they always have, as if they are 6'2, and therefore eat as they always have, within a certain range of variation, even if their height declines?



Thanks for these helpful thoughts, Captain Steel. It is certainly true that everyone loses height as they age, but what is the connection between losing height and losing weight? Logically, if someone loses height as they age, their Body Mass Index and body fat percentage both go up, not down. Also, if they do not strategically lower the amount they are eating as their height declines, they'd actually gain weight, right? Is the idea that as you lose height, your caloric needs decline as well, and so this is another explanation of why people also lose weight at the same time? I'm not sure I fully get the connection here. I understand that shorter people will have lower caloric needs than taller people, so they may eat less throughout their lives, or at least they should, but height is a relatively stable characteristic for adults. I'm not sure that if someone who was 6'2 becomes 6 foot over 10 years as they age that they then eat as if they were shorter than they've been their whole lives. Do they not act like they always have, as if they are 6'2, and therefore eat as they always have, within a certain range of variation, even if their height declines?
First, everyone is different, with different eating habits, metabolisms, or potential disease processes which can effect how they gain or lose weight, so no rules apply to everyone equally.

But yeah, eating less with age for some is a strategic decision (we call this adhering to a diet), but for others it's just a natural (non-conscious) progression. They require less calories as their metabolism slows and their body's decline, thus they are less hungry and eat less. Carry this out to it's natural progression and they weigh less as they age.

Your previous statements about slower metabolism are true for younger people - if their metabolism slows due to inactivity, yet they still eat the same as others the same age, they'll get fat.

Slower metabolism must be compensated with less food intake to lose weight, and that is the case for most (not all) elderly people - as their metabolism slows, they tend to eat less. The less they eat, the more their stomach shrinks, the less hungry they are, and the more the pounds fall off. Keep in mind this is a gradual process that can take place over decades.
In this sense, aging is like a natural, slowed & gradual version of a bariatric surgery.

I've known several people who've gotten shorter with age, but who have gotten wider - these are folks who keep eating more than their slower metabolism can burn and more than their smaller body needs.

Instead of thinking about losing height vs losing weight with age, just consider that people tend to get all around smaller as they age - this is one cause for wrinkles and drooping skin - the mass under the skin gets smaller and the skin is now too big for the body.

Unless you are an overeater (as I am) loss of weight will usually coincide with loss of height, bone density and muscle mass.



Humans aren't meant to live as long as we do.
Metabolism by the age of 50, 60, is half what it was at 30 and 40.

Average age of our various different ancestors, from Neanderthal to Homosapiens, was only around 30...

Hitting 35 and 40, I noticed huge changes in my body... my brothers are all the same and said they noticed more noticeable changes when they hit 50 and 60.

Modern diet and medicine is barely 100 years old and has fast-tracked us to living anywhere up to 100+... but we as a species have literally hundreds of thousands of years of evolution that denotes we should only go to around 30-40.

It's kinda like the modern obesity problem.

But, that has only been "a thing" for around 50 years.
As a species, again, we have literally hundreds of thousands of years of in-built evolution that denotes we should eat heartily in the Summer, and then pig out like crazy in Autumn.
Winter and Spring, we eat what we stored or whatever we could get our hands on, as nothing grew.

We still have that in-built desire to pig out... the problem, is we have, s a species today, food at our fingertips (excuse the pun) literally all the time, 25 hours a day, 8 days a week, 390 days a year.
So when food is plentiful... what do we do? We eat it.



Average age of our various different ancestors, from Neanderthal to Homosapiens, was only around 30...
Studies suggest that they had similar life expectancies to modern humans, with many living beyond 40 years. So itís not accurate to say that humans are ďmeantĒ to live only to around 30-40 based on our evolutionary history, even if modern diets and advancements in medicine have indeed contributed to an increase in human lifespan.



The only reason average lifespans used to be so short was due to very high rate of infant mortality.



The trick is not minding
The dinosaurs were all likeÖhomo saline looks kinda tasty. Iím gonna nibble on one. Ooh! Heís tastes like raptor! Only less teeth and claws!
And thus, the Neanderthal lifespan was short lived indeed.



Thanks Captain Steel. I think you've provided the most well thought out and reasoned answer that could explain this outside of the presence of chronic disease, which is what I was looking for. Are you aware of any research or studies that support the points you've made, or is this largely your own opinion?



Thanks Captain Steel. I think you've provided the most well thought out and reasoned answer that could explain this outside of the presence of chronic disease, which is what I was looking for. Are you aware of any research or studies that support the points you've made, or is this largely your own opinion?
Hmmm.. I would say my opinion is based on what I've learned & observed about biology & aging.

I watched and helped 2 parents grow old and die, sat in on countless doctor consultations along the way, and continue to work for various elderly people.

Chronic disease plays a huge role even if it's not diagnosed or classified as such. The same can be said of minor ailments...

As we age our biological systems don't function as well or as efficiently as they did when we were young - this is particularly true of the digestive & gastric systems. Many elderly people develop some sort of digestive disorder (whether it's occasional acid indigestion in response to certain foods or serious, recurrent intestinal problems). Even minor or occasional digestive problems will effect the way people eat, and the older people get, the more common it is to develop these types of problems.

Also, teeth are another factor - bad teeth, missing ones or false teeth tend to cause people to eat less over time.

Some elderly people develop problems swallowing also. I had an aunt with both these problems toward the end of her life - at holiday dinners, my mother would put all her food in a blender so she wouldn't have to chew and so swallowing was easier. Granted, my aunt was built like a toothpick at the end of her life.

We also can't rule out more practical factors as having a potential effect - the ability for elderly to go out and go shopping for food, (when you use say a community transportation service, you're usually limited to the number of bags you can carry from the market), living on a fixed income, etc. All these things may result in a person having less food at the ready and needing to conserve until they can obtain more.

So, the list of potential factors is long. Combine any few of them and it's not surprising that older people tend to lose weight