Can a Low Carb Diet Lower Blood Pressure?

High blood pressure is one of those health topics that comes up constantly when people ask me about keto. And I get it – if you have been told to watch your salt, eat less fat, and follow something like the DASH diet, a high-fat diet that tells you to add sodium sounds like it’s heading in exactly the wrong direction. I’ve been running Ruled Me since 2013, and this is easily one of the top five questions I hear from readers who want to try keto but are nervous about their cardiovascular health.

Here’s what I want to do in this article: lay out what the research actually shows about keto and blood pressure – the good, the complicated, and the parts that require real caution. Because the honest answer isn’t “keto cures hypertension” and it isn’t “keto is dangerous for your heart.” The truth is more interesting than either of those, and the details really matter if you’re someone managing high blood pressure.

We’re going to cover the evidence for blood pressure reduction on keto, the mechanisms behind it, the sodium question everyone worries about, and the critically important topic of blood pressure medications on keto – which is where the real safety concerns live. If you’re on antihypertensives, don’t skip that section.

Jump to a section:

• Does Keto Actually Lower Blood Pressure?
• How Keto Affects Blood Pressure
• What the Research Actually Shows
• The Sodium Paradox on Keto
• Keto and Blood Pressure Medications
• Potassium and Magnesium’s Role
• Who Should Be Cautious
• Monitoring Your Blood Pressure on Keto

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Does Keto Actually Lower Blood Pressure?

The short answer: in most studies, yes – but it isn’t as simple as “ketosis lowers blood pressure.” The majority of the blood pressure reduction seen on keto appears to come from weight loss, with some additional contribution from improved insulin sensitivity and the natural diuretic effect of carbohydrate restriction.

A 2024 meta-analysis pooling 23 randomized controlled trials and 1,664 participants found that the ketogenic diet reduced systolic blood pressure by 0.87 mmHg and diastolic by 0.11 mmHg compared to control diets – neither of which reached statistical significance.1A 2024 GRADE-assessed meta-analysis of 23 RCTs (1,664 participants) found keto diets did not significantly reduce systolic BP (WMD: -0.87 mmHg, 95% CI: -2.05 to 0.31) or diastolic BP (WMD: -0.11 mmHg, 95% CI: -1.14 to 0.93) compared to control diets. That might sound disappointing, but context matters here. The comparison was against other diets, not against no treatment. Many of the control groups were also losing weight, which independently lowers blood pressure.

When you look at the absolute blood pressure changes within the keto groups themselves – rather than versus controls – the picture looks better. Individual studies have documented reductions of 5 to 10 mmHg systolic, which is clinically meaningful. The issue is that other diets also produce reductions when they cause weight loss, so the question becomes: is there something special about keto beyond the weight loss? The evidence is mixed, and I think being honest about that matters more than overclaiming.

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How Keto Affects Blood Pressure

3. Reduced Sympathetic Nervous System Activity

Hyperinsulinemia also drives increased sympathetic nervous system activity, which raises blood pressure through vasoconstriction and increased heart rate.4A 2023 review in Biomedicines detailed how hyperinsulinemia promotes hypertension through increased sympathetic nervous system activity, renal sodium retention, and vascular smooth muscle proliferation – and how reducing insulin resistance through low-carb diets produces “considerable and unanticipated improvements in blood pressure.” Beta-hydroxybutyrate (BHB), the primary ketone body, has been shown to have a suppressive effect on sympathetic activity. So keto may offer a two-pronged approach: lower insulin reducing one driver of sympathetic activation, and ketones themselves providing an additional dampening effect.

4. Natural Diuresis

When you start keto, your body burns through its glycogen stores within the first few days. Every gram of glycogen is stored with 3-4 grams of water, so depleting glycogen means releasing a substantial amount of fluid. This initial diuresis reduces blood volume and can produce noticeable blood pressure drops within the first week or two. For people on blood pressure medication, this is important to be aware of – the combination can sometimes push pressure too low, too fast.

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What the Research Actually Shows

Rather than cherry-pick studies that make keto look amazing (or terrible) for blood pressure, let me walk you through the most relevant data we have.

The Meta-Analysis View

The most rigorous overall assessment comes from the 2024 meta-analysis I mentioned earlier: 23 RCTs, 1,664 people, and the conclusion was that keto didn’t produce statistically significant blood pressure reductions compared to control diets. An earlier 2012 meta-analysis of 17 controlled trials in obese patients did find reductions of 4.81 mmHg systolic and 3.10 mmHg diastolic, but those were absolute reductions rather than comparisons against control diets.5A narrative review in Nutrients cited a 2012 meta-analysis of 17 controlled trials (1,141 obese patients) showing absolute reductions of -4.81 mmHg systolic and -3.10 mmHg diastolic on ketogenic diets, and a 2009 study showing Atkins dieters achieved -7.60 mmHg systolic and -4.40 mmHg diastolic at 20 months.

The takeaway: keto lowers blood pressure in absolute terms, but when compared to other diets that also produce weight loss, the advantage narrows. The blood pressure benefit of keto appears to track with its weight loss advantage rather than being an independent effect of ketosis.

The MHERO Trial: Keto vs DASH

This is one of the most interesting studies for anyone debating between keto and the traditional blood pressure diet. A 2023 randomized trial directly compared a very low carbohydrate diet against the DASH diet in 94 adults with hypertension who also had prediabetes or type 2 diabetes.6The MHERO trial (2023, Annals of Family Medicine) randomized 94 adults with hypertension and prediabetes/type 2 diabetes to very low carb vs DASH diets for 4 months. The VLC group had greater systolic BP reduction (-9.77 vs -5.18 mmHg, p=.046), weight loss (-19.14 vs -10.34 lb, p=.0003), and HbA1c improvement (-0.35% vs -0.14%, p=.034).

The results favored the very low carb approach across the board:

Outcome	Very Low Carb	DASH Diet
Systolic BP reduction	-9.77 mmHg	-5.18 mmHg
Weight loss	-19.14 lb	-10.34 lb
HbA1c change	-0.35%	-0.14%
BP meds reduced/stopped	31-44%	5-13%

That’s a meaningful difference – nearly double the systolic reduction and nearly double the weight loss. But I want to be careful about overgeneralizing from a single study with 94 people. These were specifically people with both hypertension and metabolic disease (prediabetes or type 2 diabetes), which is a population where insulin-lowering interventions tend to shine. The results might not be as dramatic in someone with hypertension but normal blood sugar.

Real-World Primary Care Data

A UK primary care study followed 154 patients with type 2 diabetes or impaired glucose tolerance on a carbohydrate-restricted diet for an average of two years. They saw a mean systolic reduction of 10.9 mmHg and a diastolic reduction of 6.3 mmHg, along with 9.5 kg of weight loss. Perhaps most notably, the group experienced a net reduction of 35 antihypertensive medication prescriptions – a 21.5% decrease in total blood pressure prescriptions across the cohort.7An observational study of 154 patients in UK primary care found a low-carbohydrate diet produced mean reductions of -10.9 mmHg systolic and -6.3 mmHg diastolic over 24 months, with 9.5 kg weight loss and net deprescribing of 35 antihypertensive medications (21.5% of total prescriptions). That last point matters a lot in practice – the blood pressure reductions were substantial enough that doctors felt comfortable taking patients off medications they had been on for years.

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The Sodium Paradox on Keto

That said, sodium sensitivity varies between individuals. Some people’s blood pressure responds much more to sodium than others, and if you have salt-sensitive hypertension, you should be more cautious. The practical approach is to monitor your blood pressure at home (we’ll cover how below), add sodium gradually rather than all at once, and work with your doctor to find the right balance for your body. For a deeper look at managing all your electrolytes on keto, our electrolytes guide covers the full picture.

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Keto and Blood Pressure Medications

This is the most important section in this article if you’re currently on antihypertensive medication.

Keto can lower blood pressure through multiple pathways at once – weight loss, reduced insulin, natural diuresis, and reduced sympathetic activity. When you’re also taking medications designed to lower your blood pressure, these effects stack. The result can be blood pressure that drops too low, too fast, causing dizziness, lightheadedness, fainting, or in serious cases, dangerous hypotension.

A 2025 review on ketogenic diet contraindications put it bluntly: “The high efficacy of the KD may necessitate adjusting (lowering) the dosage of antihypertensive drugs or weaning them off altogether, if clinically indicated. Otherwise, a potential risk of hypotension arises.”9A 2025 review on ketogenic diet contraindications warned that the blood pressure-lowering efficacy of keto may necessitate reducing or discontinuing antihypertensive medications to prevent dangerous hypotension, and that this drug-diet interaction has not yet been thoroughly researched.

In the MHERO trial, 31-44% of participants on the very low carb diet had their blood pressure medications reduced or discontinued over just four months. Compare that to only 5-13% in the DASH diet group. In the UK primary care study, 21.5% of total antihypertensive prescriptions were eliminated over two years.

Here’s what you need to do if you’re on blood pressure medication and starting keto:

• Tell your doctor before you start. This isn’t optional. Your doctor needs to know so they can plan medication adjustments.
• Monitor your blood pressure daily, especially during the first four to eight weeks when the diuretic effect and weight loss are most dramatic.
• Watch for symptoms of low blood pressure: dizziness when standing up, lightheadedness, visual changes, feeling faint, unusual fatigue. These are signs your medication dose may need to come down.
• Never stop or adjust your medication without your doctor’s guidance. The adjustments need to be managed medically – you can’t do this safely on your own.
• Diuretic medications deserve extra attention. Keto itself acts as a mild diuretic. Combining it with prescribed diuretics (hydrochlorothiazide, furosemide, etc.) can compound fluid and electrolyte losses, increasing the risk of dehydration and electrolyte imbalances.

The good news here is clear: many people on keto are eventually able to reduce or eliminate blood pressure medications under medical supervision. That’s a truly life-changing outcome. But the transition period requires careful monitoring. For a broader look at how keto affects heart health, our dedicated article covers the full cardiovascular picture.

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Potassium and Magnesium’s Role

Magnesium

Magnesium helps relax blood vessels, and deficiency is associated with higher blood pressure. It’s also one of the most commonly depleted minerals on keto, especially early on. A meta-analysis of 34 randomized controlled trials found that magnesium supplementation (median dose: 368 mg/day) reduced systolic blood pressure by 2.00 mmHg and diastolic by 1.78 mmHg.11A meta-analysis of 34 double-blind, placebo-controlled RCTs (2,028 participants) published in Hypertension found magnesium supplementation at a median dose of 368 mg/day for a median of 3 months reduced systolic BP by -2.00 mmHg (95% CI: -0.43 to -3.58) and diastolic by -1.78 mmHg (95% CI: -0.73 to -2.82). Those reductions are modest in isolation, but they’re additive – if you’re already getting blood pressure benefits from weight loss and reduced insulin, fixing a magnesium deficiency stacks another couple of points of reduction on top.

Magnesium glycinate or magnesium citrate are the best-absorbed forms. A dose of 200-400 mg per day is a reasonable target for most people. Keto-friendly food sources include dark leafy greens, pumpkin seeds, macadamia nuts, and dark chocolate (in moderation). For the full rundown on electrolyte management on keto, that guide covers sodium, potassium, and magnesium together.

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Who Should Be Cautious

Keto can be really helpful for many people with high blood pressure, but there are situations where extra caution or medical supervision is essential:

• Anyone on antihypertensive medications. As covered above, the combination of keto’s blood pressure-lowering effects with existing medications can cause hypotension. Medical supervision during the transition is non-negotiable.
• People with resistant hypertension. If your blood pressure isn’t well-controlled even on multiple medications, dietary changes alone are unlikely to solve the problem. Work with your doctor before making any changes.
• People with chronic kidney disease. The kidneys play a central role in blood pressure regulation, and keto changes how the kidneys handle sodium, potassium, and fluid balance. If your kidneys are already compromised, these shifts need to be monitored carefully. Our article on keto risks covers kidney considerations in more detail.
• People on potassium-sparing medications. ACE inhibitors, ARBs, and potassium-sparing diuretics (spironolactone, amiloride) already increase potassium levels. Adding potassium-rich foods or supplements without monitoring can lead to dangerous hyperkalemia.
• People with salt-sensitive hypertension. About 25-50% of people with hypertension are salt-sensitive, meaning their blood pressure responds more to sodium intake. If you know you’re in this group, the standard keto advice to increase sodium needs to be adjusted in consultation with your doctor.
• Pregnant or breastfeeding women with hypertension. This is a population where blood pressure management is critical and dietary experiments carry real risk. Consult your OB/GYN before making dietary changes.

If none of these apply to you and you’re interested in using keto to help manage mild to moderate hypertension alongside (not instead of) medical care, the evidence suggests it’s a reasonable approach. The standard keto diet with 20-30g net carbs, adequate protein, and plenty of vegetables gives you the metabolic benefits while keeping your nutrient intake well-rounded.

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Monitoring Your Blood Pressure on Keto

If you have high blood pressure or are on medication for it, monitoring at home isn’t optional when you start keto. Here’s a practical framework:

Get the Right Equipment

Buy an upper-arm (not wrist) blood pressure monitor. Wrist monitors are convenient but less accurate, especially if your arm isn’t positioned correctly. Look for a monitor validated by the Association for the Advancement of Medical Instrumentation (AAMI) or equivalent. They cost $30-$60 and are a worthwhile investment.

When to Measure

• Measure at the same times each day – morning before eating and evening before bed are ideal
• Sit quietly for five minutes before measuring
• Take two readings one minute apart and average them
• Keep a log (many monitors have memory, or use a simple notebook)

What to Watch For

Situation	Action
Systolic consistently below 100 or you feel dizzy/lightheaded	Contact your doctor – medication may need reducing
Systolic consistently above 140 despite weight loss	Check sodium intake, potassium/magnesium status, and consult your doctor
BP drops more than 20 mmHg when you stand up (orthostatic hypotension)	Increase fluid and sodium intake, contact your doctor about medication adjustment
Gradual decline in BP over weeks with weight loss	This is the expected positive pattern – share your log with your doctor

The first four to eight weeks on keto are the highest-risk period for blood pressure swings, especially if you’re on medications. After that, your body generally stabilizes into a new equilibrium. Use our keto calculator to dial in your macros properly from the start – getting the right balance of fat, protein, and carbs helps avoid unnecessary metabolic stress during the transition.

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Key Takeaways

• Keto can lower blood pressure, but most of the benefit appears to come from weight loss rather than ketosis itself. A meta-analysis found roughly 1 mmHg systolic reduction per kilogram lost, regardless of diet type.
• Reduced insulin levels on keto decrease renal sodium retention, reduce sympathetic nervous system activity, and improve endothelial function – all of which contribute to lower blood pressure.
• One RCT found a very low carb diet reduced systolic BP by 9.8 mmHg over four months – nearly double the DASH diet comparison. But this was in people who also had metabolic disease, and it was a single study.
• The extra sodium recommended on keto replaces what your body is actively excreting through insulin-driven natriuresis. It isn’t the same as adding salt to a standard diet. Still, people with salt-sensitive hypertension should monitor closely.
• If you’re on blood pressure medication, keto can push your pressure too low. Up to 31-44% of participants in one study needed medication reductions. Never adjust medications without your doctor.
• Potassium (2,500-3,500 mg/day from food) and magnesium (200-400 mg/day supplemented) both contribute modest but meaningful blood pressure reductions and are commonly depleted on keto.
• Home blood pressure monitoring is essential during the first four to eight weeks of keto, especially if you’re on medications.

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Frequently Asked Questions

Does the keto diet lower blood pressure?

In most studies, yes, but the reduction tracks closely with weight loss. Every kilogram lost reduces systolic pressure by about 1 mmHg. Since keto often produces greater weight loss than other diets, it frequently leads to real BP improvements. A 2023 RCT found a very low carb diet reduced systolic BP by 9.8 mmHg – nearly double the DASH diet comparison. However, a 2024 meta-analysis of 23 RCTs didn’t find a statistically significant difference when keto was compared directly against control diets.

Can I stay on my blood pressure medication while doing keto?

Continue your medication, but talk to your doctor about monitoring. Keto can lower blood pressure through weight loss and diuresis, and the combination with existing medications can push pressure too low. In one study, 31-44% of very low carb participants needed their antihypertensive medications reduced or discontinued. Never adjust doses on your own. Monitor daily and report any dizziness, lightheadedness, or fainting to your doctor.

Does the extra sodium on keto raise blood pressure?

Not in the way you might think. Keto causes your kidneys to excrete more sodium because lower insulin reduces sodium reabsorption. Adding 1-2 grams of extra sodium replaces what your body is flushing rather than accumulating on top of normal levels. Research shows that even participants consuming 6,100 mg of sodium daily on keto showed urinary sodium levels similar to baseline. For people with salt-sensitive hypertension, cautious monitoring is still warranted.

Is keto better than the DASH diet for high blood pressure?

One head-to-head RCT in people with hypertension and prediabetes or type 2 diabetes favored the very low carb approach – 9.8 mmHg systolic reduction versus 5.2 mmHg for DASH, along with nearly double the weight loss. But this is a single study in a specific metabolic population. The DASH diet has decades of evidence for blood pressure and works well for many people. Both are legitimate options, and the best diet is the one you’ll stick with long-term.

How long does it take for keto to lower blood pressure?

Some blood pressure reduction can happen within the first one to two weeks, driven by the diuretic effect of glycogen depletion and falling insulin levels. One observational study found a systolic reduction of about 10.5 mmHg within the first three months, with no further notable changes after that. The initial drop tends to be fast; sustained improvements depend on ongoing weight loss. If you’re on blood pressure medication, monitor from day one because the early changes can be substantial.

Sources

• Effect of Ketogenic Diet on Blood Pressure: A GRADE-Assessed Systematic Review and Meta-Analysis of Randomized Controlled Trials – Nutrition, Metabolism and Cardiovascular Diseases (2024)
• Influence of Weight Reduction on Blood Pressure: A Meta-Analysis of Randomized Controlled Trials – Hypertension (2003)
• Comparing Very Low-Carbohydrate vs DASH Diets for Overweight or Obese Adults With Hypertension and Prediabetes or Type 2 Diabetes: A Randomized Trial – Annals of Family Medicine (2023)
• Substantial and Sustained Improvements in Blood Pressure, Weight and Lipid Profiles from a Carbohydrate Restricted Diet – International Journal of Environmental Research and Public Health (2019)
• Insulin Resistance, Obesity, Hypertension, and Renal Sodium Transport – International Journal of Nephrology (2011)
• Insulin Resistance and Hypertension: Mechanisms Involved and Modifying Factors for Effective Glucose Control – Biomedicines (2023)
• Ketogenic Diet, Physical Activity, and Hypertension: A Narrative Review – Nutrients (2021)
• Effects of Hypocaloric Low-Fat, Ketogenic, and Ketogenic and Ketone Supplement Diets on Aldosterone and Renin – The Journal of Clinical Endocrinology & Metabolism (2023)
• The Ketogenic Diet Is Not for Everyone: Contraindications, Side Effects, and Drug Interactions – Nutrients (2025)
• Effects of Magnesium Supplementation on Blood Pressure: A Meta-Analysis of Randomized Double-Blind Placebo-Controlled Trials – Hypertension (2016)
• Magnesium and Potassium Supplementation for Systolic Blood Pressure Reduction in the General Normotensive Population – Nutrients (2024)
• The Ketogenic Diet and Cardiovascular Diseases – Nutrients (2023)

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Medical Disclaimer

This article is for informational purposes only and is not medical advice, diagnosis, or treatment. High blood pressure is a serious cardiovascular condition that requires professional medical management. If you’re experiencing a hypertensive crisis (systolic above 180 or diastolic above 120), seek emergency medical care immediately. Don’t start, stop, or adjust blood pressure medications based on information in this article. Any dietary changes should be discussed with your healthcare provider, especially if you’re taking antihypertensive medications, have chronic kidney disease, have resistant hypertension, or are pregnant. The information here is intended to help you have a more informed conversation with your doctor – not to replace that conversation.