How to Lower Blood Pressure Naturally: What Each Thing Is Actually Worth, in mmHg

The best-evidenced thing you can do about blood pressure without a prescription is a diet nobody is selling you. It beat twenty-one other lifestyle interventions and it moved systolic pressure by about 7 mmHg. [1]

The best exercise for it turned out to be holding a wall sit, which beat running, lifting and intervals across 270 trials. [2]

And the supplements marketed for blood pressure came in at the bottom of the list, using their own best numbers.

Two words first, because everything below is measured in them. Systolic is the top number — the pressure while your heart is actually pushing. mmHg is millimetres of mercury, which is just the scale blood pressure has always been measured on; there is no American version of it. A reading of 130 over 80 means systolic 130, diastolic 80.

The whole thing on one page

Read down the middle column and the shape of the advice industry becomes obvious: the things with no product attached are at the top.

The winner is a diet from 1997 that nobody has monetised

In 2020 a Bayesian network meta-analysis went through 60,166 articles, kept 120, and compared 22 different non-drug interventions across 14,923 people. [1]

The DASH diet came first, and not narrowly: 6.97 mmHg off systolic (the plausible range ran 4.50 to 9.47) and 3.54 off diastolic. The reviewers graded that as high-quality evidence, which is the top rung and rarer than it sounds. [1]

DASH stands for Dietary Approaches to Stop Hypertension. It is vegetables, fruit, wholegrains, low-fat dairy, less salt, less red meat and less sugar. It is thirty years old, it is free, and there is nothing in it to put in a bottle. That is very likely why you have heard less about it than about beetroot.

Also effective in the same analysis, at moderate-to-high quality: aerobic exercise, isometric training, low-sodium and high-potassium salt, breathing control, meditation, and in people carrying extra weight, a lower-calorie diet. [1]

The exercise result that surprised everybody, including us

A 2023 network meta-analysis pooled 270 randomised trials and 15,827 people to rank exercise modes against each other. [2]

Everything worked. Aerobic training took off 4.49 systolic, dynamic resistance 4.55, intervals 4.08, and combining aerobic and resistance work 6.04. [2]

Isometric training took off 8.24. [2] Isometric means holding a position under load rather than moving through a rep — and when the reviewers looked at which specific version did most, the wall sit came out top for systolic pressure. Running came out top for the diastolic number. [2]

A note on how confident to be about that. The ranking uses a statistic called SUCRA, which is simply the probability that a treatment is among the better ones — 100% would mean it beat everything in every simulation, 50% is middling. Isometric scored 98.3%, combined training 75.7%, and the rest sat between 39% and 47%. [2] That is a clear ordering. It is still an ordering built from fewer isometric trials than aerobic ones, which is the usual reason a newcomer tops a ranking.

Where the two analyses disagree, we are not going to pick. The 2020 paper puts DASH first at 6.97 with high-quality evidence; the 2023 paper puts isometric exercise at 8.24. Different reviews, different comparator sets, run three years apart. They are not one ranking and nobody has run the study that would make them one.

Salt: the effect is real, and short studies hide it

133 randomised trials, 12,197 people, with sodium intake measured properly through 24-hour urine collection rather than asked about on a questionnaire. [3]

Cutting sodium took 4.26 mmHg off systolic and 2.07 off diastolic, and the effect scaled with the size of the cut. [3]

The interesting finding is about study length. In trials shorter than fifteen days, each unit of sodium reduction bought about 1.05 mmHg. In longer trials the same reduction bought 2.13 — roughly double. [3] Short studies underestimate salt. Anyone quoting a two-week trial to tell you salt does not matter is quoting the half of the literature built to miss it.

The effect was also larger in older people, in people whose pressure was already higher, and in non-white populations. [3] Worth knowing that the electrolyte industry sells you the opposite instruction, on much thinner evidence.

And the supplements

We have already checked the two sold hardest for blood pressure, and both of them work — just not by much.

Magnesium takes about 2.0 mmHg off systolic across 34 double-blind trials. That is a real effect and it is the most defensible thing on the magnesium shelf. It is also less than half what cutting salt does, and about a quarter of a wall sit.

Beetroot juice manages about 3.55 mmHg. Genuinely more than magnesium. Still below sodium reduction, and it is the one on this page you have to keep buying.

“Exercise works as well as the pills” — where that came from, and what it leaves out

You have probably seen this claim. It comes from a 2019 network meta-analysis of 391 randomised trials — 197 of exercise, 194 of blood pressure medication. [4] It is a serious paper. The headline version of it is not.

Three things the paper says that the headline does not.

First: no trial compared them directly. [4] Not one. Every exercise-versus-drug number is an indirect comparison, worked out by chaining each against its own control group. That is a legitimate method and it is not the same as a head-to-head.

Second: in the overall analysis, the medications won — by 3.96 mmHg, with a plausible range of 2.91 to 5.02. [4]

Third: the similarity shows up only in one slice. Among people who actually had high blood pressure, the reviewers found no detectable difference between the common drug classes and endurance or resistance exercise. [4] But only 56 of the 197 exercise trials enrolled hypertensive people, covering 3,508 participants — while every single medication trial did. [4] The comparison that produces the headline rests on the thinnest part of the exercise evidence. The reviewers also note the exercise trials carried a higher risk of bias, mostly from not being blinded.

So: none of this is a reason to stop taking, skip, or delay blood pressure medication. That is a conversation with a doctor and nothing on this page substitutes for it. The honest reading of that paper is that exercise is worth doing and is under-studied in the people who need it most — not that it replaces a prescription.

What this adds up to

If you want the short version, ranked by how much evidence sits behind it rather than by how loudly it is sold:

— The diet does most, and it is the one with nothing to buy. [1]
— Any exercise works; holding a position may work best, and the training itself is worth having for other reasons. [2]
— Cutting salt is worth about twice what a magnesium capsule is, and short trials undersell it. [3]
— The supplements are last, by their own numbers.

And the part that is genuinely important: high blood pressure usually has no symptoms at all. If you do not know your number, none of this ranking is your first step — getting it measured is, and if it is high, that belongs with a clinician rather than a shopping list. How we grade evidence like this, and the simplest version of moving more.