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Vitamin D may slow cellular aging by preserving telomeres, study finds

22 May 2025 | Supplements, Aging, Top Health | 0 comments

Vitamin D is best known for building strong bones, but new research suggests it might also help keep cells young. Recent findings from a major clinical trial indicate that daily Vitamin D supplementation can slow down the shortening of telomeres, the protective caps on our DNA that shrink as we age. While it may not be a magic pill for immortality, this evidence points to a specific biological mechanism where the “sunshine vitamin” fights the aging process at a cellular level.

Daily Vitamin D helps keep DNA markers younger

The strongest evidence comes from a specific sub-study of the VITAL trial, a massive research project designed to test the long-term effects of supplements.

The telomere connection

Telomeres are often compared to the plastic tips at the end of shoelaces. They sit at the ends of our chromosomes and protect our genetic data. Every time a cell divides, its telomeres get a little shorter. When they get too short, the cell can no longer divide and becomes inactive or dies. This process is a primary marker of biological aging.

Evidence from the VITAL study

In the VITAL sub-study published in The American Journal of Clinical Nutrition, researchers followed over 1,000 adults who took either 2,000 IU of Vitamin D3 daily or a placebo. After five years, the group taking Vitamin D had significantly longer telomeres than the placebo group.

The difference was roughly 140 base pairs of DNA. To put that number in perspective, telomeres typically shorten by about 35 to 40 base pairs per year during normal aging. This suggests that the supplement preserved the equivalent of about 3 to 4 years of cellular aging over the course of the trial. The effect was most visible in people who did not have obesity and those who were not taking cholesterol medication.

It fights disease but might not extend maximum lifespan

While Vitamin D helps cells look younger under a microscope, the evidence on whether it actually helps people live longer lives is more complex.

Cancer and heart health

Vitamin D does not seem to prevent cancer from starting, but it may help prevent people from dying of it. Several large analyses, including data from the VITAL trial, show that while overall cancer rates remain similar between users and non-users, the rate of death from cancer is lower in those who take Vitamin D.

For heart health, the picture is mixed. Some studies link low Vitamin D levels to a higher risk of heart attacks, suggesting that correcting a deficiency is crucial. However, taking extra Vitamin D when levels are already normal does not consistently prevent heart problems in large trials.

Mixed results on total lifespan

Despite the positive signs for cellular health and cancer survival, huge population studies like the Australian D-Health Trial have found that Vitamin D supplementation does not necessarily increase overall life expectancy for the general population.

This distinction is important: Vitamin D helps the body function correctly and may reduce the severity of certain diseases (improving “healthspan”), but it has not been proven to simply add years to the maximum human lifespan in the way that calorie restriction might in animal models.

Risks and how much is too much

Because Vitamin D is fat-soluble, it builds up in the body. Taking too much can lead to toxicity, a condition that is rare but dangerous.

Hypercalcemia and kidney risks

The main risk of excess Vitamin D is hypercalcemia, a condition where calcium levels in the blood become too high. This can weaken bones, create kidney stones, and interfere with how the heart and brain work. Symptoms often include nausea, vomiting, and weakness.

Most experts and health agencies suggest an upper limit of 4,000 IU per day for adults to stay safe, unless a doctor prescribes more for a specific deficiency. The 2,000 IU dose used in the VITAL study is generally considered safe for long-term daily use.

Daily vs. monthly dosing

How you take the supplement matters. The VITAL study used a daily dose, which mimics the steady supply the body gets from the sun. In contrast, the D-Health trial used a massive monthly bolus dose (60,000 IU once a month). The monthly approach showed fewer benefits, suggesting that a steady, daily intake is more effective for metabolic health than infrequent large spikes.

What you can do about it

If you want to support your cellular health, consider these steps:

  • Check your levels: Ask your doctor for a simple blood test (25-hydroxy vitamin D) to see if you are deficient. This is the most important step.
  • Consider a daily dose: If you supplement, a daily dose of 1,000 to 2,000 IU is supported by the VITAL data for telomere preservation. Avoid sporadic mega-doses.
  • Pair with K2: Some research suggests taking Vitamin K2 alongside D3 helps ensure calcium goes to your bones rather than your arteries, though this is still being studied.
  • Don’t ignore lifestyle: Vitamin D is just one piece of the puzzle. Lifestyle counts far more than genetics for health and longevity, so prioritize sleep, exercise, and diet first.

Sources & related information

The American Journal of Clinical Nutrition – Vitamin D3 supplementation and leukocyte telomere length – 2024

A randomized trial showing that daily supplementation of 2,000 IU of Vitamin D3 significantly reduced telomere shortening compared to placebo over a 5-year period.

The Lancet Diabetes & Endocrinology – The D-Health Trial – 2022

A large-scale randomized trial involving over 21,000 participants which found that monthly high-dose Vitamin D supplementation did not reduce all-cause mortality in the general older population.

BMJ – Vitamin D and risk of cause specific death – 2014

A systematic review and meta-analysis suggesting that Vitamin D3 supplementation significantly reduces mortality from cancer, though evidence for other causes of death remains less clear.

Disclaimer: The information shared here is for awareness only. Review the provided sources, cross-check with other trusted references, and talk about it with qualified healthcare professionals before making any medical decision.

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Listening is the underrated skill that makes you a better leader instantly

We often think of great leaders as great talkers. We imagine them giving rousing speeches, setting a clear vision, and having an answer for everything. But a massive review of scientific research suggests we have it backward. The most effective way to improve your leadership isn’t to speak more; it is to listen better.

New data shows that listening is not just a “soft skill” for making friends – it is a hard driver of job performance and professional success.

144 studies confirm listening drives performance

A recent meta-analysis published in the Journal of Business and Psychology examined the link between listening and work outcomes. The researchers looked at data from 144 studies involving more than 155,000 people.

Their conclusion was clear: listening has a strong, positive effect on employee job performance.

Leaders who are perceived as good listeners do more than just make their employees feel warm and fuzzy. They actually get better results. The study found that listening improves the quality of relationships at work, which in turn boosts performance. When employees feel heard, they perform better. This dynamic helps leaders unlearn bias and lower conflict within teams.

As the researchers noted, the link between listening and positive job outcomes is “robust.” They suggest that listening is an underrated predictor of job performance – a simple cause of superior results that many organizations overlook.

Why we love to talk about ourselves

If listening is so effective, why is it so hard? Why do so many of us default to talking instead?

The answer lies in our biology. A study published in the Proceedings of the National Academy of Sciences (PNAS) found that talking about ourselves is inherently rewarding. In fact, humans devote about 30–40 percent of everyday speech to informing others about their own subjective experiences – their thoughts, feelings, and opinions.

Using brain scans, researchers found that self-disclosure activates the mesolimbic dopamine system – the same brain regions associated with the pleasure we get from food, money, and sex. It feels good to talk about yourself.

The drive is so strong that people in the study were willing to give up money just to keep talking about themselves. When given a choice between answering questions about others for a higher payment or answering questions about themselves for a lower payment, participants voluntarily gave up between 17 and 25 percent of their potential earnings to talk about their own views.

We are wired to broadcast. To lead effectively, you have to fight that wiring.

The power of follow-up questions

You can become a better listener instantly by changing how you ask questions. It is not enough to just stay silent; you need to show you are engaged.

Research published in the Journal of Personality and Social Psychology found that the specific type of question you ask matters. The study showed that asking follow-up questions – questions that ask for more detail on what the other person just said – dramatically increases how likable you appear.

When you ask a follow-up question, you prove you were listening. You signal validation, care, and understanding. This simple habit makes you more persuasive and influential because, as other research in Frontiers in Psychology shows, likable people are better at influencing those around them.

Asking follow-up questions and recalling small details are among seven habits that mark an exceptional listener, and this research confirms it is a key tool for leaders.

Feeling known leads to feeling supported

Listening does more than build rapport; it meets a fundamental human need.

A study in the Journal of Personality and Social Psychology found that employees feel less objectified when their boss knows them as people, rather than just as workers or numbers. Furthermore, research linked to the Journal of Experimental Psychology suggests that “feeling known” is a necessary precursor to “feeling supported.”

You cannot support an employee you do not know. You cannot help them reach their career goals if you never asked what those goals were. You cannot solve their roadblocks if you never listened to what those roadblocks are.

What you can do about it

To become a better leader today, flip the ratio of your conversations.

  • Talk less. Recognize that your brain wants the dopamine hit of talking about yourself. Resist it.
  • Ask for their story, not yours. Instead of telling your team about your weekend or your problems, ask about theirs.
  • Use the follow-up rule. When an employee answers, do not just nod and move on. Restate what they said or ask one follow-up question based on what they just said.
  • Listen to learn. You already know what you know. The only way to learn something new is to listen to what others know.

Mastering conversation: how active listening keeps dialogue engaging is a skill you can practice in every interaction, whether with a colleague, a client, or a friend.

Sources & related information

Journal of Business and Psychology – The Power of Listening at Work – 2023

A meta-analysis of 144 studies involving 155,000 observations found that perceived listening is strongly correlated with improved job performance and relationship quality.

Proceedings of the National Academy of Sciences – Disclosing information about the self is intrinsically rewarding – 2012

Neuroimaging research shows that self-disclosure activates the brain’s reward systems, motivating people to talk about themselves even at a financial cost.

Journal of Personality and Social Psychology – It Doesn’t Hurt to Ask – 2017

A series of studies demonstrates that asking follow-up questions increases interpersonal liking by signaling responsiveness and listening.

The Pratfall Effect: why making mistakes can make you more likable

Perfection is often overrated. While we strive to be flawless in job interviews or first dates, psychology suggests that being too perfect can actually push people away. A small blunder, like tripping or spilling a drink, might do more for your popularity than a flawless performance. This phenomenon is known as the Pratfall Effect.

What is the Pratfall Effect?

The Pratfall Effect is a psychological principle that states that a person’s likability increases when they make a clumsy mistake, but only if that person is already perceived as competent.

Social psychologist Elliot Aronson first identified this effect in 1966. He wanted to test how mistakes influence attraction. In his famous experiment, he asked male college students to listen to tape recordings of people answering quiz questions.

The participants heard one of two main scenarios:

  1. The Superior Person: This person answered 92% of the questions correctly. They sounded confident and knowledgeable.
  2. The Average Person: This person answered only 30% of the questions correctly.

Aronson then added a twist. In some recordings, the “Superior Person” commits a blunder at the end: they are heard spilling a cup of coffee and reacting to the mess.

The results were clear. The students rated the Superior Person who spilled the coffee as the most likable of all. The blunder made the highly competent person seem more human and approachable.

The catch: competence is key

There is a crucial condition to this effect. A mistake only helps you if you have already established your competence.

In Aronson’s experiment, when the “Average Person” (who missed most quiz questions) spilled the coffee, their likability rating dropped even further.

  • If you are competent: A mistake humanizes you. It breaks the “too good to be true” barrier and prevents others from feeling threatened by your perfection.
  • If you are incompetent: A mistake just reinforces the idea that you are not capable. It acts as proof of inadequacy.

This distinction is vital. You cannot simply be clumsy and expect to be popular. You must first demonstrate that you are good at what you do. The blunder acts as a softener for your competence, not a substitute for it.

Real-world examples: from Jennifer Lawrence to brands

We see the Pratfall Effect in action in celebrity culture and marketing.

The relatable celebrity

Jennifer Lawrence is often cited as a modern example. Her frequent trips on the red carpet or candid, unpolished interviews often endear her to the public. Because she is an Oscar-winning, highly successful actress (high competence), these slips make her seem “down to earth” rather than clumsy.

The honest brand

Marketing experts use a similar concept known as the “blemishing effect.” When a brand admits a small flaw, consumers often trust it more. For example, Guinness: the beer brand famously turned a negative – the long time it takes to pour a pint – into a legendary slogan: “Good things come to those who wait.”

Why perfectionism harms connection

The Pratfall Effect challenges the idea that we must hide our flaws to be accepted. In social situations, perfection creates distance. We often struggle to connect with someone who seems to have no weaknesses because we cannot relate to them. This relates to understanding conversational biases to become more likable, where showing genuine engagement often matters more than saying the perfect thing.

When a competent person slips up, it levels the playing field. It signals vulnerability. This vulnerability fosters trust and signals that the person is authentic, not a curated persona.

What you can do about it

You do not need to stage accidents or spill coffee on purpose. However, you can change how you react to your own errors.

  • Don’t hide every flaw: If you are good at your job, admitting a small error or a gap in knowledge can make you more approachable to your team.
  • Own your blunders: When you trip or misspeak, laugh it off. Trying to cover it up often looks worse than the mistake itself.
  • Build competence first: Remember that this effect relies on a foundation of skill. Focus on being capable and reliable first.
  • Accept imperfection in others: Just as your mistakes humanize you, seeing others stumble is a reminder that everyone is human. This perspective can help reduce judgment and social anxiety.

Sources & related information

Elliot Aronson – The Effect of a Pratfall on Increasing Interpersonal Attractiveness – 1966

The original study published in Psychonomic Science where Aronson and his colleagues demonstrated that a blunder increases the attractiveness of a superior person but decreases the attractiveness of a mediocre person.

The Guardian (ZenithOptimedia) – The Pratfall effect and why brands should flaunt their flaws – 2015

An analysis of how brands like Guinness and VW use the Pratfall Effect to build trust by admitting minor weaknesses, making their core claims more believable.

Journal of Consumer Research – The blemishing effect – 2012

Research showing that under certain processing conditions, a small amount of negative information can actually enhance the positive impression of a product.

Endmyopia claims to reverse nearsightedness naturally (but science remains skeptical)

Imagine never needing your glasses again. No surgery, no contacts, just… fixing your eyes yourself. That’s the big promise of Endmyopia, a popular online method created by Jake Steiner. He claims you can reverse nearsightedness (myopia) just by changing your habits.

It sounds awesome, right? But before you throw away your glasses, you need to know that most eye doctors and scientists say it’s not that simple. Here is the lowdown on what this method is, why people try it, and why the medical consensus says it probably won’t work like you think.

The big claim: “Your glasses are the problem”

Endmyopia is based on a simple idea: your eyes aren’t broken; they are just reacting to your environment.

It starts with a muscle cramp

The theory goes like this: when you spend hours staring at your phone or laptop, a focusing muscle inside your eye gets tired and cramps up. This is called pseudo-myopia. At first, your vision is only blurry because of this cramp.

Then your eye grows longer

The controversial part is what happens next. Steiner says that when you wear glasses to fix that blur, your eye physically grows longer to “adapt” to the lenses. A longer eyeball is what causes true nearsightedness. Basically, the method claims your glasses trap you in a cycle that makes your vision worse.

The “fix”: training your eyes

To reverse this, Endmyopia tells you to do two things:

  1. Use weaker glasses: Instead of your full prescription, you wear weaker glasses for close-up work (like homework or gaming) to stop the eye strain.
  2. Practice “Active Focus”: This is a mental trick. You look at something far away that is slightly blurry (like a street sign) and try hard to make it clear just by focusing. The idea is that this effort forces your eyeball to shrink back to its normal size.

What science says

Here is the problem: Eye doctors agree that once your eyeball grows too long, it usually stays that way. It’s like your height – once you grow tall, you don’t shrink back down just because you want to.

Your eyeballs aren’t like muscles

You can train a muscle to get bigger, but you can’t really train an eyeball to get shorter. While atropine drops or special contact lenses can slow down eye growth in kids, there is no scientific proof that you can reverse it significantly once it’s happened.

Wearing weak glasses might backfire

Trying to fix your eyes by wearing weaker glasses can actually make things worse. A famous study (Chung et al., 2002) showed that under-correcting vision (wearing glasses that are too weak) made kids’ eyes grow faster, not slower. Blurry vision seems to signal the eye to keep growing, which is the exact opposite of what you want.

Why do some people swear it works?

If science says it doesn’t work, why are there so many success stories online? Read on Reddit: I was able to effectively fully cure myopia with my own methodology of eye exercises and discussions about do eye exercise really work?.

Brain training vs. Eye shrinking

When you practice looking at blurry things, your brain gets smarter at guessing what it’s seeing. This is called blur adaptation. You might be able to read a sign further away, not because your eyes are fixed, but because your brain is better at decoding the fuzzy image. You are “seeing” better, but your nearsightedness hasn’t actually disappeared.

Is there any hope?

Interestingly, some new research on red light therapy shows that specific light treatments might slightly shorten the eye.

Is it worth trying?

Trying to fix your eyes this way takes a huge amount of time – years of daily practice. Walking around (or driving!) with blurry vision can be dangerous.

Sources & related information

Study: Weak glasses make eyes worse (2002)

A major study showed that giving kids weaker glasses actually made their nearsightedness get worse faster.

Experts: Can you reverse myopia?

Eye doctors explain that while eye spasms can be fixed, the actual shape of a nearsighted eye is permanent.

Endmyopia Website

The source of the “active focus” method and the theory that glasses are to blame.

Red Light Therapy Study (2022)

A study showing that a specific type of red light therapy could shrink the eye slightly, proving some change is possible.