Posted on 03/25/2024 1:09:47 PM PDT by Red Badger
Research in mice shows limited intakes of one particular essential amino acid can slow the impacts of aging and even lengthen their lifespan.
Scientists are now wondering if these findings could help people improve their longevity and quality of life.
Isoleucine is one of three branched-chain amino acids we use to build proteins in our bodies. It is essential for our survival, but since our cells can't produce it from scratch, we have to get it from sources like eggs, dairy, soy protein and meats.
But there can always be too much of a good thing. Earlier research using data from a 2016-2017 survey of Wisconsin residents had found dietary isoleucine levels were linked with metabolic health and that people with higher BMIs were generally consuming much greater quantities of the amino acid.
"Different components of your diet have value and impact beyond their function as a calorie, and we've been digging in on one component that many people may be eating too much of," metabolism researcher Dudley Lamming from the University of Wisconsin, US, who was involved in both studies, explained in November when the new findings were published.
"It's interesting and encouraging to think a dietary change could still make such a big difference in lifespan and what we call 'healthspan,' even when it started closer to mid-life."
In the most recent study, a genetically diverse group of mice was fed either a diet containing 20 common amino acids as a control, a diet where all amino acids were reduced by about two-thirds, or a diet where only isoleucine was reduced by the same amount.
The mice were around six months old at the start of the study, which is the equivalent age of a 30-year-old person. They could eat as much as they wanted, but only from the specific kind of food provided to their group.
Restricting dietary isoleucine increased the lifespan and healthspan of the mice, reduced their frailty, and promoted leanness and glycemic control. Male mice had their lifespans increased 33 percent compared to those whose isoleucine was not restricted, and females had a 7 percent increase.
These mice also scored better in 26 measures of health, including muscle strength, endurance, blood sugar levels, tail use, and hair loss.
The male mice in this group had less age-related prostate enlargement, and were less likely to develop the cancerous tumors that are common in the diverse mice strains.
Curiously, the mice given low isoleucine food also ate significantly more calories than the others. But rather than gaining weight, they actually burned more energy and maintained leaner body weights, even though their activity levels were no different.
Graphical abstract shows dietary isoleucine was restricted by 67%, charts showing blood glucose and body weight declining over time / age respectively, reduced frailty and cancer, increased lifespan (survival improved by 33 percent)
A visual summary of the impact the reduced isoleucine diet had on mice in the study. (Green et al., Cell Metabolism, 2023)
The researchers think restricting isoleucine in humans, either by diet or pharmaceutical means, has the potential to yield similar anti-aging effects - although, as with all mice studies, we won't know for sure until it's actually tested in humans.
This is easier said than done. Although the food provided to the mice was controlled, the researchers noted that diet is an incredibly complex chemical reaction, and there may be other dietary components involved in producing these results.
Restricting protein intake in general, for instance, has detrimental effects on the body, mouse or human. Translating this research for real-world human use is more complicated than just reducing intake of high-protein foods, even though this is the simplest way to limit isoleucine intake.
The amino acid restriction level was constant in all experiments, and they acknowledge that more fine-tuning may be required for optimum effects across different mice strains and sexes – when it comes to diet, one size does not fit all.
"We can't just switch everyone to a low-isoleucine diet," Lamming said.
"But narrowing these benefits down to a single amino acid gets us closer to understanding the biological processes and maybe potential interventions for humans, like an isoleucine-blocking drug."
The research was published in Cell Metabolism.
An earlier version of this article was published in November 2023.
I started eating my favorite foods at age 55. Foods with high fat, high cholesterol, high sodium, high sugar foods. Because they are the tastiest. 30 years later I am still in good health, with caveat I am a fanatic about staying active.
“ we have to get it from sources like eggs, dairy, soy protein and meats.”
In other words from food.
Apparently orcs had restaurants. “Menu”
“”Smells like BS to me.
I remember when an article came out a few years ago saying that L-Carnitine causes cancer. Guess what has the most L-Carnitien? Beef””
I believe the real ‘news’ would be one or more laboratory mice WHO DO NOT end up with cancer. The ‘scientists’ pour massive amounts of whatever they are testing into a mouse.
Also:
“”people with higher BMIs””
Just like the Food Pyramid, the BMI index has also been ‘adjusted.’ I remember an article criticizing the new BMI. While he was still playing basketball, Michael Jordan was ‘obese’ according to the new BMI index. Garbage In Garbage Out.
Many turtles are omnivores. My son’s pet box turtle loved raw hamburger. Snapping turtles eats birds, fish, frogs, etc... .
It is a fact that isoleucine is necessary for the growth of muscle tissue.
It is also a fact that the more muscular a person is, the longer they live, on average (you really, REALLY don’t want to be frail headed into old age, you’re going to die a lot sooner).
So this study is telling you that limiting a key amino acid in the maintenance and growth of muscle will help you live longer…which is utter BS, according to another set of studies.
Make it ice cream, please!
It is more of what makes “nutrition science” utter garbage. “...research using data from a 2016-2017 survey of Wisconsin residents had found dietary isoleucine levels were linked with metabolic health and...higher BMIs...”
Yes, people eating the Standard American Diet AND also eating lots of “eggs, dairy, soy protein and meats” tend to be fat. And fat people tend to have bad health. But is it the essential amino acid, or all the carbs found in the Standard American Diet?
Well, let’s find out by studying animals (mice) that, as you point out, almost never eat stuff with high levels of isoleucine. “In the wild, they prefer grains, fruits, and seeds...Mice are particularly fond of these types of foods because they are high in carbohydrates which equates to lots of energy for these small animals that are always on the move. While their diet is primarily vegetarian...”
So while mice, like humans, CAN eat almost anything, it is likely their optimum health comes from eating foods low in isoleucine.
What about humans? Well, we sure can’t tell much from a survey in Wisconsin on people eating huge amounts of highly processed foods!
And it would be easy to find out how it works in humans because pretty much ANYONE eating a “Carnivore” diet would be eating a diet uncommonly high in isoleucine. And what happens to people on the Carnivore diet? Well...they tend to have great health! Not obese and certainly not struggling with diabetes and/or “metabolic health” issues, including obesity.
We KNOW the answer already. So what is driving this bogus “science”? Could it be vegans and the anti-meat people pushing their anti-meat agenda?
And there was the doozy of a study the other day saying that Intermittent Fasting will lead to heart attacks.
“but live lot less years than herbivores such as elephants, turtles” and MICE and DEER and lots of animals with very short lives!
Zoe Harcombe just reviewed “A recent presentation at an American Heart Association conference generated global headlines. It claimed that eating within an 8-hour window each day was linked to a 91% higher risk of cardiovascular death.”
Since she charges for her newsletter - which I love and it well worth the nominal price - I wont quote it at length. But not surprisingly, “The claims for CVD deaths were based on 31 events in 20,078 people. The groups and eating windows were so uneven that bias must be suspected. And all of this relates to two attempts to remember what was eaten yesterday, 20 years ago.”
They did the entire study based on TWO food questionnaires, asking what people ate (in and what time frame) during the previous 24 hours - done in 2003 & 2005!
YGBSM! That was before intermittent fasting was done! Two questionnaires done over 20 years ago, trying to get a snapshot of 24 hours each, and we’re supposed to believe people have continued to eat that way for the last 20 years? Jason Fung wrote The Complete Guide to Fasting in 2016, a dozen years AFTER the two questionnaires!
Oh...and Wikipedia’s article on Jason Fung notes, “Fung’s book The Obesity Code received a 31% score for scientific accuracy and an overall score of 60% by Red Pen Reviews.[16] The reviewer Seth Yoder commented that several of the main claims of the book are poorly supported by science including the idea that elevated levels of insulin are the primary cause of obesity.” No bias there, eh?
Me? Keto and IF finally got me off the Yo-Yo Diet syndrome that lasted 45 years in my case! 45 years of trusting government and having my weight go up and down 40 pounds. It has now been stable for 7 years (at the low end) and I’m on Medicare while running 4 miles a day FOR FUN! And weightlifting.
But ignore my body and submit to government officials who study mice...
Or you can say, Carnivores such as tigers, leopards, hyenas have strong bodies AND live lot MORE years than herbivores such as antelopes, wild goats or groundhogs.
Absurd response. Antelopes and wild goats are killed by predators, not die from natural deaths. The subject of thread is longevity based on diet.
LOL you are confusing deaths from predators versus longevity based on diet.
They can cure cancer, baldness, sexual abnormally, heridiidty diseases …l in mice for the last 20 years. Good thing our new mouse overlords will be well cared for.
“The researchers think restricting isoleucine in humans, either by diet or pharmaceutical means,”
I predict the next big fad and money maker for the drug companies. Another killer drug on the way.
Longest lived lion — 25 -29 years
Longest lived leopard — 25 years
Longest lived hyena —27 years
Longest lived goat -— 22 years
Longest lived springbok ( common African antelope) —19 years
Longest lived groundhog — 15 years
The carnivores win.
“Male mice had their lifespans increased 33 percent compared to those whose isoleucine was not restricted, and females had a 7 percent increase.”
Isoleucine is misogynistic, sexist, and part of The Patriarchy. It’s probably racist, too, but this hasn’t been studied yet.
I have started cheating with bacon. My arthritis pain is almost gone.
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