Low-Dose Aspirin Use May Increase Your Risk of Anemia by 23%

Aspirin has a reputation that’s basically the medical version of a family recipe: everyone swears by it, no one remembers where it came from,
and somehow it shows up at every gathering. For decades, “a baby aspirin a day” sounded like a harmless grown-up habitlike drinking prune juice
or owning a drawer full of flashlights.

But newer research has been politely clearing its throat and saying, “Hey… about that.” One large, well-run study in older adults found that daily
low-dose aspirin was linked to a meaningful increase in incident anemiaoften summarized as around a 20%–23% higher risk.
That doesn’t mean aspirin is “bad,” or that everyone should panic-toss their pill bottles into the sea. It does mean aspirin is a real drug with real tradeoffs,
and “low-dose” doesn’t automatically equal “no big deal.”

Let’s break down what that “23%” actually means, why anemia is even part of the aspirin conversation, who might need extra monitoring,
and how to have a smart, no-drama talk with a clinician about whether aspirin still belongs in your daily routine.

What the “23% Higher Risk” Actually Means

It’s not 23 out of 100 peoplethankfully

Headlines love a spicy number. In this case, the study result is often reported as a ~23% increase, but the core published finding is best understood as a
relative increase in risk over time, not “23% of people became anemic.”

In a post-hoc analysis of the ASPREE randomized trial (community-dwelling older adults taking 100 mg aspirin daily vs placebo), researchers tracked anemia over
several years. They found anemia occurred more often in the aspirin group, reported as a hazard ratio around 1.20roughly a 20% higher rate
compared with placebo. Some write-ups translate that into “about 23% higher risk,” depending on the metric and rounding used.

Absolute risk still matters (because your body lives in reality, not percentages)

The same analysis reported anemia incidence rates of roughly 51.2 vs 42.9 events per 1,000 person-years (aspirin vs placebo).
In other words: anemia wasn’t rare in this age group, and aspirin nudged the odds higher.

The practical takeaway: if you’re an older adult using daily low-dose aspirinespecially for primary prevention (trying to prevent a first heart attack or stroke)
it may be worth monitoring hemoglobin and iron status periodically, because changes can be gradual and easy to miss.

Why Would Aspirin Raise Anemia Risk?

Aspirin’s main “superpower” is also its main “side effect.” It reduces clotting by interfering with how platelets stick together. That’s helpful when a clot could
block blood flow to the heart or brain. But it also makes bleedingespecially slow, sneaky bleedingmore likely.

1) Slow gastrointestinal blood loss (the classic culprit)

The digestive tract is a common trouble spot. Aspirin can irritate the stomach lining and, because it affects platelets, it can make tiny bleeds more persistent.
Sometimes this bleeding is obvious. Often it’s occult (hidden), meaning you don’t see itbut your iron stores notice.

Over months or years, chronic blood loss can drain iron and contribute to iron-deficiency anemia. That’s the version of anemia most people recognize:
low iron means your body can’t make enough hemoglobin, and hemoglobin is the oxygen-delivery system your muscles and brain would very much like to keep.

2) Falling ferritin (iron stores) even without “major bleeding”

One of the more eyebrow-raising parts of the ASPREE analysis: the association with anemia appeared even when major bleeding events didn’t explain it.
Researchers also reported a greater drop in ferritin (a marker of iron storage) among aspirin users, and a higher proportion with low ferritin after a few years.

Translation: you might not have a dramatic bleeding episode and still end up with gradually declining iron stores.

3) Anemia is common in older adults for many reasonsaspirin may be the “extra straw”

Anemia in older adults isn’t a single-story problem. It can be related to nutrition, chronic inflammation, kidney disease, medications, gastrointestinal conditions,
and more. Aspirin may not be the whole cause for everyonebut it can push someone closer to the line where hemoglobin dips low enough to qualify as anemia.

Signs of Anemia You Shouldn’t Brush Off

Anemia can be quiet at first. Some people feel “a little off” and blame stress, sleep, or birthdays that come with more candles than they used to.
Common symptoms can include:

• Unusual tiredness or weakness (especially with activity)
• Dizziness or headaches
• Shortness of breath with exertion
• Heart palpitations or a faster-than-usual heartbeat
• Trouble concentrating (your brain running on “low battery” mode)
• Pale skin or feeling cold more than usual

None of these symptoms automatically mean anemia (or aspirin-related anemia). They’re just reasons to consider asking for a basic lab check,
especially if you’re in a higher-risk group and taking daily aspirin.

Who’s Most Likely to Be Affected?

The study that sparked the “23%” conversation focused on older adultsprimarily people in their late 60s, 70s, and beyond.
Risk can be higher if you also have factors that increase bleeding or reduce iron:

• History of stomach ulcers, gastritis, or prior gastrointestinal bleeding
• Use of other blood thinners or antiplatelet drugs (or frequent NSAID use)
• Chronic kidney disease or certain chronic inflammatory conditions
• Low iron intake, poor absorption, or restrictive diets without careful planning
• Colon polyps, hemorrhoids, or other GI conditions that can bleed
• Older age plus frailty, falls, or other reasons bleeding would be especially risky

Importantly, the aspirin/anemia signal doesn’t mean younger people are “immune.” It just means the best evidence behind this specific percentage comes from older adults,
and the risk-benefit math changes with age.

When Low-Dose Aspirin Still Makes Sense

Here’s where nuance lives (and where headlines go to avoid doing homework). Aspirin remains a standard part of care for many people with
established cardiovascular diseasefor example, after a heart attack, certain types of stroke, or specific heart proceduresbecause the
benefit in preventing another event can outweigh bleeding risks for some patients.

Meanwhile, for primary prevention (preventing a first event), guidance has shifted. In the U.S., the decision is now much more individualized,
and some groupsespecially older adultsare generally advised not to start daily aspirin for primary prevention due to bleeding risk and smaller net benefit.

The key point: aspirin isn’t “one-size-fits-all.” It’s “one-size-fits-your-medical-history-and-your-bleeding-risk-and-your-age-and-your-other-meds.”
Not as catchy, but much safer.

What to Do If You’re Taking Daily Aspirin

Don’t stop abruptly just because a headline scared you. (That’s how you end up with a pile of half-finished supplements and a very confused primary care doctor.)
Instead, consider a calm, structured check-in with a clinician. Helpful questions include:

• Why am I taking aspirin? Primary prevention vs secondary prevention matters.
• What’s my bleeding risk? Age, GI history, and other meds change the calculus.
• Should I monitor labs? Hemoglobin and possibly ferritin can provide early clues.
• Do I have anemia symptoms? Even mild fatigue can be worth mentioning.
• Are there alternatives? Sometimes other strategies reduce risk with less bleeding potential.

If labs show anemia, clinicians typically look for a causeoften including evaluation for occult gastrointestinal bleedingrather than assuming
“it must be the aspirin.” But aspirin can be part of that bigger picture.

Supporting Healthy Iron Without Getting Weird About It

If iron deficiency is a concern, food can helpthough it’s not a magical “undo” button for medication-related bleeding. Still, building iron-friendly meals is
a solid move (and tastes better than worrying).

Iron-rich foods (and absorption helpers)

• Heme iron (more easily absorbed): lean red meat, poultry, seafood
• Non-heme iron: beans, lentils, tofu, spinach, fortified cereals, pumpkin seeds
• Vitamin C boosts absorption: citrus, strawberries, bell peppers, tomatoes

Common absorption “speed bumps”

• Drinking tea/coffee right with iron-rich meals (tannins can reduce absorption)
• Very high calcium intake at the same time as iron (timing can matter)

If a clinician recommends iron supplementation, follow their guidancetoo much iron isn’t a fun hobby, and the best plan depends on your labs and your cause.

Experiences: What This Looks Like in Real Life (and Why People Miss It)

The tricky thing about anemia linked to low-dose aspirin is that it rarely announces itself with a marching band. It’s more like a slow leak in a tire:
everything feels mostly fineuntil it doesn’t. Here are a few real-world-style scenarios (composites, not individual stories) that show how this often plays out.

1) The “I’m just getting older” fatigue spiral.
A person in their early 70s has taken daily low-dose aspirin for years “because it’s good for the heart.” They start noticing that stairs feel steeper,
afternoon naps feel less optional, and workouts have mysteriously become “not their thing.” Nothing is dramaticno obvious bleeding, no ER visit.
At a routine appointment, basic labs show hemoglobin is down compared with prior years. Ferritin is lower too. It’s not a crisis, but it’s enough to trigger
a more careful look: are they bleeding slowly from the GI tract? Are they getting enough iron? Are there other contributors (kidney function, inflammation, diet)?
The biggest surprise isn’t the diagnosisit’s how long the symptoms were shrugged off as “normal.”

2) The “double whammy” medication combo.
Another common pattern: someone takes low-dose aspirin and also uses over-the-counter pain relievers frequently for knee, back, or shoulder pain.
Add occasional heartburn, a little stomach irritation, and you’ve got a setup where the GI tract gets annoyed and platelets are less able to “patch” tiny bleeds.
Over time, iron stores can drift downward. The person may not connect the dots because each medication seems reasonable on its ownespecially when both are sold
without fanfare. In clinic conversations, this is often where “medication reconciliation” (a fancy phrase for “tell me everything you take”) becomes incredibly useful.

3) The “but my friend takes it!” comparison trap.
Aspirin decisions are famously contagious. One friend reads a headline about preventing heart attacks. Another was prescribed aspirin after a cardiac event.
Suddenly, it feels like everyone is doing it, so it must be universally smart. But aspirin is a different deal in secondary prevention (after a heart attack or stroke)
versus primary prevention (trying to avoid a first event). In real life, clinicians spend a lot of time clarifying this difference because it changes the risk-benefit
calculationespecially as people age and bleeding risk climbs. The “my neighbor does it” argument is emotionally comforting, but biologically… not evidence-based.

4) The “numbers look fine… until they don’t” slow drift.
In the ASPREE anemia analysis, hemoglobin was measured yearly. That annual snapshot mirrors how many people experience anemia: a slow decline that doesn’t look alarming
on any single day. Then one year it crosses a threshold and suddenly it’s labeled “anemia.” Many people feel frustrated because it seems to appear out of nowhere.
In reality, it’s often been developing quietly. That’s why periodic monitoringespecially for older adults on long-term aspirincan be valuable. It turns a surprise into
a trend line, and trend lines are much easier to act on thoughtfully.

The shared theme in these experiences is simple: anemia is easy to miss when it’s gradual, and aspirin-related effects can be subtle.
If aspirin is truly needed for heart or stroke prevention, the goal isn’t fearit’s awareness, monitoring, and smart risk management with a clinician.

Conclusion

Low-dose aspirin can be lifesaving in the right contextand unnecessarily risky in the wrong one. The “23% higher anemia risk” headline comes from a real signal seen
in a large study of older adults: daily low-dose aspirin was associated with a higher rate of developing anemia and a greater decline in iron stores over time.

The smartest response isn’t to panic or to self-prescribe. It’s to understand why you’re taking aspirin, recognize that anemia can creep in quietly,
andif you’re an older adult on long-term aspirinconsider whether periodic monitoring of hemoglobin (and sometimes ferritin) makes sense for you.
If anything feels off, bring it up early. Your future self will appreciate the oxygen.