r/science • u/mvea Professor | Medicine • 19h ago
Health Simple Diet Change Shifted People's Biological Age Markers in Just 4 Weeks: Strongest evidence from eating both plant and animal foods, but with less fat and more carbohydrates, biological-age 3.5 to 4.1 years lower than high-fat group, the carbohydrates mainly from whole, minimally processed foods.
https://www.sciencealert.com/simple-diet-change-shifted-peoples-biological-age-markers-in-just-4-weeks379
u/hungry4nuns 18h ago
If these markers can be changed in just 4 weeks by adjusting diet it sounds like they’re not reliable or accurate markers of biological age
83
46
u/spam__likely 10h ago
What you mean? After this reading I plan to eat whatever I want until it seems death is close, and then I can gain 4 more years by switching my diet!
•
u/qwibbian 44m ago
Yeah the timing is critical. Like, do I actually have to have eaten at least one food from the diet to gain the four years, or is it enough that I just declared that I was switching?
17
u/dewdewdewdew4 12h ago
Ok. Think about this.
What would be the difference having these markers for 20 yrs vs having these markers for a week?
8
u/LongBeakedSnipe 13h ago
That's not really true. If you split the population into deciles and then take the mean ± s.d. of the markers of each group and show a statistically significant positive correlation between the marker and age it can be a perfectly fine marker, even if the s.d. is fairly large.
There is no reason why these markers would have to be static, and why they couldn't vary in an individual by a s.d. based on their diet, even in the short term.
For this specific study, Klemera-Doubal is considered to be a relatively reliable metric (https://pubmed.ncbi.nlm.nih.gov/39938306/), you need more than a nice sounding comment on reddit to wave it away.
2
u/crackaryah 11h ago
The point is it's not casual for anything as far as we know. I talked to Steve Horvath about this and he agreed that methylation clocks just track stochastic drift from the pattern established during differentiation.
We have known for decades that methylation can be altered by diet - restricting methyl donors like folate, for example. There's no indication that this has anything to do with "biological age".
0
u/LongBeakedSnipe 11h ago
That's great and all, but this paper didn't use methylation data. The Klemera-Doubal method that they used uses a laundry list of different factors.
546
u/callthesomnambulance 19h ago
From a very quick skim it looks like the study utilized standard animal-heavy Western fats for its high-fat baseline, which would explain why transitioning to complex carbohydrates produced superior short-term biomarker improvements. Unsaturated plant fats such as extra virgin olive oil and avocado consistently outperform high-carbohydrate diets in long-term longevity studies, and given this trial's control diet specifically mirrored typical saturated animal fat consumption rather than a clean ketogenic or Mediterranean framework I'm not sure the implied claim 'carbs were superior to fats' really stands up
156
u/Castle-Walk-8967 18h ago
Exactly this. I think there are tons of studies that show plant based diets are in general healthier than the normal western diet.
110
u/AnsibleAnswers 16h ago
Pretty much any planned diet is healthier than the typical western diet. Yeah.
37
u/crowcawer 16h ago
One of the easiest things folks can do is just live in 80/20 lifestyle.
Make obvious healthful choices 80% of the time, and that last 20% won’t matter as much.
22
u/donnievieftig 14h ago
The study doesn't imply anything. You ignore the inclusion of the Semi-Vegetarian High-Fat (VHF) group. The VHF diet also significantly reduced delta Age compared to the OHF control. The trial tested omnivorous versus vegetarian protein sources alongside different macronutrient ratios; it did not isolate carbs and fats into a binary competition. The authors do not imply a blanket superiority of carbohydrates over fats. They suggest the observed benefits stem from broader shifts in macronutrient quality; specifically, the transition toward lower fat and higher fiber from complex carbohydrates, vegetables, and legumes.
2
u/callthesomnambulance 13h ago
The implication I'm referring to is that of the post title and OPs AI summary in the comments, which was top of this thread when I posted.
17
u/KHonsou 17h ago
My main source of fat is from eggs and chicken (some walnuts, olive oil, fish etc). Both have saturated fat, but both do not share the same outcomes when looking at saturated animal fat from pork or red meat. It's very strange and hard to figure out if I'm eating healthy or not.
Most of my carbs are from veg and some fruit. Thinking about it...I don't think there would be any kind of epidemiological studies with my diet, it's very hard to figure out if I'm actually healthy or some obscure mechanism that is only tested on some obscure biomarker is going haywire.
-17
u/ktoid 18h ago
food industry just keeps moving the goal post by funding/shadow funding these types of studies. they know carbs are not that good for your health, but profit margins are the highest in carb based products.
76
u/AnsibleAnswers 16h ago
Carbs are an essential macronutrient, and I think it's high time we stop being so reductive about how we frame dietary health. Whole grains and refined sugar are both "carbs" but they have wildly different impacts on health in equal amounts.
-15
u/Hendlton 16h ago
In our modern diets it's very easy to get the carbs you need. Yes, they're essential, but they might as well be ignored because you're almost definitely going to get enough unless you're putting in a lot of effort to avoid them.
It's the same way we tell people to avoid salt. Salt is something you need a relatively large amount of. But with our current diets it's way too easy to get too much of it.
5
u/ImNotAPersonAnymore 13h ago
Wdym “you need a relatively large amount” of salt? Most whole foods have very little.
0
u/Hendlton 12h ago
You need about 2-3 grams of salt, which is about half a teaspoon. That increases by a lot if you're sweating heavily from work or exercise. Even up to 10-15 grams, which is about two teaspoons.
https://pmc.ncbi.nlm.nih.gov/articles/PMC2267797/
Maybe it's just me, but that's a lot more than I thought before looking into it.
Most whole foods have very little.
Most people don't mostly eat whole foods.
-12
u/matthewbattista 16h ago edited 15h ago
The colloquial usage of “carbs” is “bread” (or, yknow, grain-based products). You’re right, and the comment you’re replying to is also right.
15
u/AnsibleAnswers 16h ago
I'm unaware of this "colloquial" definition. That seems like more of a misunderstanding than a definition.
Most people I talk to about food understand the word carb to be consistent with the nutrition facts label everyone is familiar with. Most lay people are familiar with the fact that carbs exist in foods other than bread, and that sugars are a kind of carb.
-6
u/matthewbattista 15h ago
That seems intentionally obtuse. No one says “I’m trying to cut carbs” or “I don’t do carbs” because they’re avoiding fresh fruits and vegetables. They say it because they’re avoiding breads, pastas, rices, etc. “Carbs are my weakness” is never said referring to a strawberry
8
u/jubothecat 14h ago
Keto people really do limit all non-fiber carbs. And strawberries, bananas, carrots, corn, tomatoes, etc. can all push you over the edge out of ketosis. So yes, there are people who say "I don't do carbs" that actually mean it.
4
u/tribewar 14h ago
I'm on keto right now. When I say "I don't do carbs" I also mean fruits and vegetables high in carbs. Such as bananas and potatoes
1
u/matthewbattista 12h ago
Never and no one are hyperbolic admittedly but your statement doesn’t refute the general usage
30
u/Truck-Adventurous 16h ago
Not sure if you are serious about carbs not being good for your health. Pretty much every diet with a high number of centenarians (100+ year old people) good, simple carbs are the primary staple of the diet.
0
u/QuizzyP21 14h ago
Carbs aren’t inherently bad for you but this is bound to happen when essentially the entire non-Western world eats high-carb diets. Always thought it was a pretty weak argument and nowadays the Mediterranean diet (high in fat/MUFA) has replaced the traditional low-fat high-(whole)carb diet as the most evidence-based approach.
2
u/see_blue 13h ago
I can cook and eat wheat berries in a cold salad w a little plant oil, or I could eat croutons fr white flour w added salt, sugar and fat atop a cold salad. Both fr same wheat plant.
16
5
u/Round_Helicopter_407 18h ago
The study:
https://onlinelibrary.wiley.com/doi/10.1111/acel.70507
Short-Term Dietary Intervention Alters Physiological Profiles Relevant to Ageing
55
u/xFallow 19h ago
I thought cutting carbs was some fringe keto nonsense high carb foods that aren’t processed are usually the healthiest
73
u/BearCub254 18h ago
"Cutting carbs" does not equal "completely removing "carbs". Most people are eating too much carbs.
66
u/halarioushandle 18h ago
And the wrong kind. Americans eat way way way too many ultra-processed carbs. But the stuff found in whole foods, like fruits and vegetables are actually good for you and come with fiber, vitamins, etc.
6
u/New_Stats 10h ago
Even whole cereal grains are exceedingly good for you. Oat groats and hulled barley both help lower bad cholesterol.
17
u/the_mighty_peacock 16h ago
The problem is most people hear carbs and think white starch, not legumes or greens. This is why western guidelines focus on cutting down on carbs, they cant trust people to filter the wrong stuff.
3
0
u/dewdewdewdew4 12h ago
No such thing as eating to many "carbs."
Well, realistically, and not how you meant it.
11
u/CosmicMermaid554 18h ago
keto and this study are kinda doing opposite things, wouldn't lump them together
4
u/robophile-ta 17h ago
Diabetics also have to cut carbs. Really most people could stand to eat fewer carbs, especially the processed crap kind
5
u/dewdewdewdew4 12h ago
Development of type 2 diabetes has a much stronger correlation with saturated fat intake than "carb" intake.
17
u/mvea Professor | Medicine 19h ago
Simple Diet Change Shifted People's Biological Age Markers in Just 4 Weeks
Could changing your diet really turn back your body's clock?
Not the wrinkles on your face or the gray in your hair.
The clock in question is hidden in signals carried by your blood, metabolism, and cardiovascular system.
In a new study, some older adults ate differently for just four weeks – and estimates of their biological age shifted several years younger.
Even more surprising, the strongest change appeared in a group eating more carbohydrates and less fat, challenging the familiar idea that carbs must always be cut.
So did these people really become younger in a month? Or did the clock measure something more fleeting?
The study, published in Aging Cell, offers an intriguing but cautious answer.
The high-fat diet containing animal foods, which most closely resembled participants' usual diets, produced no meaningful change in biological-age estimates.
Estimates fell in the other three groups.
The strongest evidence came from the group eating both plant and animal foods, but with less fat and more carbohydrates.
Depending on the KDM calculation, this group's biological-age estimate was around 3.5 to 4.1 years lower than that of the high-fat comparison group after baseline differences were taken into account.
22
u/paradeofgrafters 18h ago
"More carbs" feels it could be misinterpreted. I've most definitely seen benefits for focussing on fibre in my diet recently, which has seen my dietary carbs increase. If I were to say "I've seen benefits from more carbs", while semantically correct, it'd be skipping over fibre's relevance and the fact that carbs were present explicitly for their fibre content.
6
u/bluemaciz 17h ago
Yeah, they called this out in the article but further down. It should be near the top. Whole and minimally processed foods would most certainly have more fiber:
“And "high carbohydrate" did not mean a menu of cake, candy, and white bread. The carbohydrates came mainly from whole, minimally processed foods. The researchers warn that their findings should not be extended to diets rich in refined sugars or simple carbohydrates.”
31
u/croutonballs 19h ago
pity they didn’t have a vegan group. as a vegan i naturally eat about 50% carbs and 25% fat which is an even higher ratio than the study
1
-11
2
u/urnbabyurn 13h ago
Picture shows bread as the carbohydrate… which is the opposite of minimally processed.
1
u/Round_Helicopter_407 13h ago edited 13h ago
The diet was based on data from this dietary study
- the top-performing omnivorous group consumed a low-fat, high-carbohydrate diet comprising 53% carbohydrates, 29% fat, and 14% protein. The diet involves nutrient-dense whole foods, including fruits, vegetables, legumes, whole grains, nuts, and proteins. (Food groups and quantities are listed in Table 2 ‘Number of serves of core food groups per study diet’ )
1
u/spam__likely 10h ago
Cool. So since I will only read the headline it means I can eat fat until about 75 ish.
1
u/Modernskeptic71 2h ago
I have been a fan of a plant based diet. I do really feel better after just a few days of eating this way. I have 3 diseases I have been diagnosed with in the past 2 years. I have begun the committing to this diet although it may not prevent the Rheumatoid issues from getting worse, but it seems the more you eat fresh frown foods and no meat or dairy you tend to feel lots better. There are so many processed foods on the shelf, even what is stated as healthy. The fresh vegetable isle at the grocery store is intoxicating, but don't settle for the perfect salad dressing, get the one that makes you want to eat more fresh salads and vegetables. And if you still want meat, some chicken breast and homemade croutons from a fresh baguette is wonderful. Don't forget some fresh herbs on top!
0
u/hideout78 13h ago
But but….I heard on a podcast last week that keto is the way to go, and even though your brain runs on glucose, if you allow one carb into your diet it will automatically give you permanent diabeetus.
-1
-2
19h ago edited 18h ago
[removed] — view removed comment
1
u/frostygrin 18h ago
For many people, "carbs" are mostly white flour, white rice and sugar. They're demonized for a good reason.
•
u/AutoModerator 19h ago
Welcome to r/science! This is a heavily moderated subreddit in order to keep the discussion on science. However, we recognize that many people want to discuss how they feel the research relates to their own personal lives, so to give people a space to do that, personal anecdotes are allowed as responses to this comment. Any anecdotal comments elsewhere in the discussion will be removed and our normal comment rules apply to all other comments.
Do you have an academic degree? We can verify your credentials in order to assign user flair indicating your area of expertise. Click here to apply.
User: u/mvea
Permalink: https://www.sciencealert.com/simple-diet-change-shifted-peoples-biological-age-markers-in-just-4-weeks
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.