Supplements for heart health: what the trials show, ranked by evidence

No supplement has been shown to prevent heart attacks in healthy people. A few lower one number, such as triglycerides, LDL cholesterol or blood pressure, but trials that counted heart attacks and strokes often found no benefit from them, and a few found harm ^{1 6}. For every bottle, check which of the two it has evidence for: a lower lab number, or fewer heart attacks and strokes.

Lifestyle and the underlying cause come first, because they set the size of any effect a supplement could add. A statin typically lowers LDL cholesterol by 30 to 50 percent; the best LDL-lowering supplements manage around 5 to 10 percent ¹⁵. If your LDL or blood pressure is high, the cause (diet, genetics, weight, kidney disease, thyroid, medicines) matters more than the pill you add on top. For how a statin shows up on your results, see the <a href="/compounds/statins">statins and your labs guide</a>. New to lipid panels? <a href="/learn/how-to-read-your-lipid-panel">How to read your lipid panel</a> explains each line first.

Free, no accountRead your blood testHolding a lipid panel? Read every line of it free before you decide what, if anything, to add.Read my results

The best supplements for heart health, ranked by evidence

The table ranks each supplement by the strongest kind of evidence it has. Outcome evidence means a trial counted cardiovascular events (heart attacks, strokes and deaths from heart disease). Marker evidence means trials only measured a lab number or blood pressure. The dose column is the amount the trials used, not a dose to take on your own. Supplements without a LifeFrom guide are included so the comparison is complete.

Supplements with a heart evidence base

Strong for triglycerides, mixed for eventsOmega-3 (fish oil)Lowers triglycerides; the one outcome win came from a purified prescription formIn our shop

Early evidenceBerberineLowered LDL and triglycerides in short trials; many drug interactionsIn our shop

Moderate evidenceMagnesiumSmall blood pressure drop in trials; most useful when your level is lowIn our shop

Outcome evidence in heart failure onlyCoQ10Fewer cardiovascular events in one heart failure trial; no prevention benefit shownIn our shop

Pick by the number you want to change

Start from the number on your results, because a supplement that lowers triglycerides does nothing for Lp(a), and one that nudges blood pressure does nothing for LDL.

High LDL cholesterol or ApoB

Start by reading your own <a href="/biomarkers/ldl-cholesterol">LDL cholesterol</a> result. Psyllium, plant sterols, berberine and red yeast rice all lower LDL. A 2018 meta-analysis found psyllium lowered LDL by about 13 mg/dL and lowered ApoB as well ¹². The 2019 European lipid guidelines put plant sterols at roughly a 7 to 10 percent LDL reduction at about 2 grams a day ¹⁵. Red yeast rice works because it contains a statin, so it carries statin side effects without statin quality control. For why ApoB can disagree with LDL, see <a href="/compare/apob-vs-ldl">ApoB vs LDL</a>, and for the condition itself, <a href="/conditions/high-cholesterol">high cholesterol</a>. If your lab did not report LDL directly, the <a href="/calculators/ldl">LDL calculator</a> works it out from your panel.

High triglycerides

Omega-3 fats lower triglycerides more reliably than they lower anything else. A 2019 American Heart Association advisory found that prescription omega-3 at 4 grams a day lowers triglycerides by about 20 to 30 percent when they are 200 to 499 mg/dL, and by 30 percent or more at 500 and above ¹⁴; whether it fits you is a decision to make with your doctor. Alcohol, refined carbohydrate, uncontrolled diabetes and an underactive thyroid raise triglycerides, and fixing the cause usually moves the number further than a capsule.

Blood pressure

Magnesium and garlic both lower blood pressure slightly. A 2016 meta-analysis of 34 trials found magnesium, at a median of about 370 mg a day, lowered it by about 2.0/1.8 mmHg (2 points off the top number and just under 2 off the bottom) ¹¹. That is real but small next to cutting salt or losing weight. Licorice root can raise blood pressure and turns up in teas and supplements, so check labels. More on the condition at <a href="/conditions/high-blood-pressure">high blood pressure</a>. A reading of 180/120 or higher with chest pain, breathlessness, a severe headache, confusion, weakness or vision change needs 911, not a supplement.

Palpitations and heart rhythm

Magnesium helps rhythm when a low magnesium level is the cause; see <a href="/conditions/magnesium-deficiency">magnesium deficiency</a>. Omega-3 supplements raise the risk of atrial fibrillation, mostly at doses above 1 gram a day, so they can make rhythm problems worse ⁴. If you have palpitations, read <a href="/symptoms/heart-palpitations">heart palpitations</a> before reaching for either.

Heart failure

CoQ10 is the one supplement with an outcome trial in heart failure. In Q-SYMBIO, 420 people with chronic heart failure who took 300 mg of CoQ10 a day alongside their usual treatment had fewer major cardiovascular events over two years than those on placebo, 15 percent against 26 percent ⁵. It was one trial of modest size, and CoQ10 was added to heart failure medicines, never used instead of them, so it is a question for your cardiologist. Breathlessness that is getting worse, waking you at night, or new swelling in the legs or rapid weight gain over a few days needs a prompt call to your heart team; breathlessness at rest or with chest pain needs 911.

High Lp(a)

No supplement lowers Lp(a) meaningfully. Lp(a), or lipoprotein(a), is an LDL-like particle whose level is set mostly by your genes. Niacin lowers it a little but did not reduce cardiovascular events in trials and has side effects. With a high Lp(a), ask your doctor to check <a href="/biomarkers/apolipoprotein-b">ApoB</a> and LDL and to bring those down; that is the useful step.

Does fish oil prevent heart attacks?

Shop fish oil has not been shown to prevent heart attacks in the general population. VITAL gave 25,871 US adults a 1 gram fish oil capsule or placebo and found 8 percent fewer cardiovascular events over a median 5.3 years, a gap small enough to be chance ². STRENGTH, which gave high-risk patients 4 grams a day of an EPA plus DHA product, was stopped early because it showed no benefit over corn oil ⁷. For forms and doses, see the <a href="/compounds/omega-3">omega-3 guide</a>.

The exception is REDUCE-IT. In 8,179 people already on statins with raised triglycerides, 4 grams a day of a purified EPA drug, icosapent ethyl, cut cardiovascular events by 25 percent ³. That result came from a single, purified, prescription form of EPA. The placebo was mineral oil, and a 2022 analysis of the trial found several inflammation markers and oxidised LDL rose in the mineral oil group, which may have made the gap look larger ¹⁶.

Omega-3 supplements raise the risk of atrial fibrillation. A 2021 meta-analysis of omega-3 outcome trials found about a 25 percent higher risk overall, rising to about 49 percent in trials using more than 1 gram a day ⁴. Atrial fibrillation is an irregular rhythm that raises stroke risk, so the trade-off matters most for older adults and people with a history of palpitations.

If you eat no fish, algae oil supplies EPA and DHA without the fish; the trade-offs are in <a href="/compare/fish-oil-vs-algae-oil">fish oil vs algae oil</a>.

Calcium, vitamin D and K2 can backfire

Calcium from pills and calcium from food behave differently in the arteries. A 2010 BMJ meta-analysis found <a href="/compounds/calcium">calcium supplements</a> taken without vitamin D were linked to about a 30 percent higher risk of heart attack ¹. Ten years of follow-up in the MESA study then linked supplement calcium, and not food calcium, to new calcium build-up in the coronary arteries ¹³. The MESA authors suggest a pill raises blood calcium in a spike that food does not ¹³.

Vitamin D alone is neutral for the heart in people who are not deficient: in VITAL, 2,000 IU of vitamin D3 a day did no better than placebo for cardiovascular events ⁹. A 2019 review of 277 trials linked combined calcium and vitamin D supplements to a higher stroke risk ¹⁰. Check your <a href="/biomarkers/vitamin-d-25-oh">25-hydroxyvitamin D</a> level before supplementing; being low is the reason to take it. Vitamin K2 is often sold as the fix that steers calcium into bone instead of arteries; the mechanism is plausible, but no trial has yet shown that K2 prevents heart attacks or strokes.

Read before you take these

Signal of harmCalciumPills, unlike food calcium, were linked to more heart attacksIn our shop

No heart benefit shownVitamin DNeutral for cardiovascular events in people who were not deficientIn our shop

CoQ10 and magnesium: who benefits

CoQ10 is a compound the body uses to make energy in cells, and statins lower its level in the blood. That led to its use for statin muscle aches, but trials for statin muscle symptoms have given mixed results. Its stronger case is in heart failure, where Q-SYMBIO found fewer major cardiovascular events (15% vs 26%) ⁵. CoQ10 can weaken the effect of warfarin, so <a href="/biomarkers/inr">INR</a> checks (the blood test that tracks how thin warfarin keeps your blood) matter if you take both. The <a href="/compounds/coq10">CoQ10 guide</a> covers forms.

Magnesium helps most when your level is low. <a href="/biomarkers/magnesium-serum">Serum magnesium</a>, the usual blood test, can look normal while the body's stores are short, because most magnesium sits inside cells; a <a href="/biomarkers/magnesium-rbc">red blood cell magnesium</a> test reads closer to those stores. People with kidney disease clear magnesium slowly and can build up a dangerous level, so they should not supplement without their doctor. Which form to use is in the <a href="/compounds/magnesium">magnesium guide</a>.

Supplements that don't help your heart (and a few to avoid)

A daily <a href="/compounds/multivitamin">multivitamin</a> does not protect the heart. In the Physicians' Health Study II, 14,641 male doctors took a multivitamin or placebo for a median of 11.2 years, with no drop in cardiovascular events ⁸. The US Preventive Services Task Force reviewed the field in 2022 and went further for two antioxidants.

The USPSTF 2022 review found the evidence for multivitamins insufficient to recommend for or against ⁶. Beyond those, avoid licorice root if your blood pressure is high, and treat red yeast rice with caution: products vary widely in their statin content, and some have contained citrinin, a toxin that can damage the kidneys.

Taking supplements with statins or blood pressure pills

A statin lowers LDL far more than any supplement, and adding the wrong supplement can double up or interfere. CoQ10 did not cause problems alongside statins in the trials that tested it, but has not reliably fixed statin muscle aches. The main clashes:

Show your pharmacist the full list of supplements you take, and ask before combining.

How to know if a supplement is working

The way to know is a baseline number before you start and a repeat test 8 to 12 weeks later, measured the same way. Match the test to the supplement's job.

1. 1Fibre, plant sterols, berberine or red yeast riceRecheck LDL and ApoB. LDL can vary by around 10 percent between tests on its own, so a small drop may be noise; confirm a change with a repeat test before drawing conclusions.
2. 2Omega-3Recheck fasting triglycerides, since a meal can raise triglycerides for several hours.
3. 3Magnesium or garlic for blood pressureUse a home blood pressure monitor: several morning and evening readings over a week, before and after.
4. 4Background markersRead hs-CRP (high-sensitivity C-reactive protein, a marker of inflammation) and homocysteine as context about risk. Lowering homocysteine with B vitamins did not reduce heart attacks in trials, so use these to judge overall risk rather than as numbers to push down.

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Your cholesterol ratios, in context

Two ratios that say more than any single number. Nothing leaves your browser.

Total cholesterolmg/dLHDL-Cmg/dLTriglyceridesmg/dL

Enter all three numbers to see your ratios.

Educational, not a diagnosis. TG/HDL thresholds are population-dependent and a surrogate for insulin resistance, not a diagnosis of it. Bands describe the values, not you.

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Before your next appointment, write down your LDL, triglycerides and blood pressure, list every supplement you take, and ask your doctor: is my number high enough that a statin or prescription EPA would do more than a supplement? For the wider picture of heart markers and what moves them, see the <a href="/for/heart">heart health hub</a>.