Intro: The ketogenic diet (a.k.a. keto) is a high-fat, low-carb eating plan that’s caught fire for promising rapid weight loss and improved metabolic health. But as the popularity of keto grows, some experts are raising a big question: could keto be putting more people at risk for high blood pressure (hypertension)?

High blood pressure isn’t something to mess with. It’s one of the main risk factors for cardiovascular disease, strokes, and a host of other serious health problems. Nearly half of U.S. adults have it, so understanding what causes it—and what makes it worse—is critical. Given the surge in keto devotees, researchers are digging into how this fat-heavy diet might impact hypertension.

The Great Keto Debate: Heart Health Hero or Hypertension Trigger? Research is all over the map when it comes to keto and blood pressure. Some studies suggest keto could lower blood pressure by helping people lose weight and boost insulin sensitivity. On the other hand, other studies argue that keto might increase blood pressure due to its high-fat content, especially saturated fats, and higher sodium levels common in low-carb processed foods.

The problem? Conflicting data makes it hard to know which side is right. That’s why a group of researchers decided to dive into 11 years of data from the National Health and Nutrition Examination Survey (NHANES) to see if there’s a real link between keto and hypertension.

The Study in Plain English:

  • Researchers analyzed a massive database covering the diet and health status of tens of thousands of people.
  • They focused on adults and looked specifically at their blood pressure, dividing people into two groups: those with hypertension and those without.
  • They calculated something called the “Dietary Ketogenic Ratio” (DKR), which is basically a formula to see how “keto-friendly” a person’s diet is based on their fat, protein, and carb intake.
  • They considered other factors like age, lifestyle, BMI, physical activity, and underlying health conditions, which are known to influence blood pressure.

What They Found: The results might make keto fans a little uneasy. A higher DKR (meaning a stricter keto diet) was associated with a greater risk of hypertension. And while this link was significant for middle-aged and older adults, young people under 40 didn’t show the same pattern.

Here’s the kicker: the association between keto and high blood pressure was stronger in people aged 40 and up, with the sharpest risk increase happening in the 40–60 age group. In other words, as people got older, sticking to a keto-heavy diet seemed to correlate more with higher blood pressure.

Why Might Keto Raise Blood Pressure? A few potential culprits could be at play here:

  1. Sodium Imbalance: Many keto followers lean on processed meats, cheeses, and other low-carb foods that can be sodium-heavy. Excess sodium is a big no-no for blood pressure.
  2. Potassium Deficit: High-fat, low-carb diets may be lacking in potassium-rich foods (like fruits and some vegetables), and low potassium can make high blood pressure worse.
  3. Weight and Insulin Factors: Keto is famous for quick weight loss and improved insulin sensitivity in the short term, but the long-term effects on blood pressure and insulin remain murky. Some studies even hint that prolonged keto might mess with insulin resistance.
  4. Chronic Inflammation: The jury’s still out, but some researchers suspect that high-fat diets might encourage a little too much inflammation, leading to stiffening of blood vessels, which can mean higher blood pressure.

Does This Mean You Should Quit Keto? Not necessarily. But if you’re over 40 and sticking to keto, it might be worth a conversation with your doctor about blood pressure. Even small tweaks—like choosing leaner proteins, reducing sodium, and balancing your diet with a bit more potassium—could go a long way.

The Takeaway: While keto might still be a solid choice for some, this study shows it’s not a one-size-fits-all solution. High blood pressure risk is real, especially as you get older. So, if you’re on keto and want to keep your heart in check, consider tailoring your plan to avoid hypertension pitfalls. Because, in the end, the best diet is the one that keeps your whole body—heart included—in peak condition.

Qu X, Liu Y, Huang L, Wan F. Ketogenic diets are associated with an elevated risk of hypertension: Insights from a cross-sectional analysis of the NHANES 2007-2018. Int J Cardiol Cardiovasc Risk Prev. 2024 Oct 10;23:200342. doi: 10.1016/j.ijcrp.2024.200342. PMID: 39484088; PMCID: PMC11525463.