【When Medication Alone Isn’t Enough】What to Eat for Resistant Hypertension, How to Tackle Hidden Salt, Sugar, and Gut Health, and Tips for the DASH Diet

“I’m taking my blood pressure medication properly, so why won’t my blood pressure come down at all…”

“I’ve been told my blood pressure is high for over 10 years. Even with more medication, nothing changes, and I don’t know what to do anymore…”

“I thought I was careful about salt, so why isn’t my blood pressure improving?”

Taking blood pressure medication but still not seeing your numbers come down, or not being able to get them stable, is actually a very common situation.

Medically, this is called “resistant hypertension” (also known as treatment-resistant hypertension).

One often-overlooked reason medication doesn’t work is “problems with diet.”

The more you feel “I’m cutting back on salt, but it still won’t come down,” the more worthwhile it is to take a close look at what’s actually in your meals.

In this article, I’ll explain in detail the deep connection between resistant hypertension and eating habits, and the dietary approach that’s key to improving blood pressure.

Please note: never reduce or stop your blood pressure medication on your own, and make changes to your diet while consulting your doctor.

What Is “Resistant Hypertension,” When Blood Pressure Medication Stops Working Well?

Resistant hypertension is a condition in which blood pressure doesn’t reach the target (generally below 140/90 mmHg) despite taking three or more types of blood pressure medication at appropriate doses.

Blood pressure is the force with which blood pumped out by the heart pushes against the walls of your blood vessels; if you compare it to a garden hose, it’s the “water pressure.”

If the hose gets stiff or the amount of water flowing through it increases, the water pressure keeps rising.

In Japan, there are said to be about 43 million people with high blood pressure, and some estimates put the share diagnosed with resistant hypertension at 10 to 30% of them.

That’s a pretty large number of people.

Main Reasons Medication Doesn’t Work

Resistant hypertension involves many intertwined causes.

Secondary hypertension is when blood pressure rises because of another illness.

In this case, treating the underlying illness takes priority, so it’s very important to tell your doctor honestly that “my blood pressure won’t come down even with medication.”

Over-the-counter drugs such as painkillers, Kampo (traditional Japanese herbal) medicines containing licorice root, and some supplements can also affect blood pressure, so tell your doctor or pharmacist about everything you take.

Medication adherence means “whether you’re taking your medication as prescribed,” and if you often miss doses, the medication can’t work as intended.

Of these, “dietary problems” are very often something people aren’t aware of themselves.

You may think you’re cutting back on salt when you actually haven’t cut back enough, or eating habits other than salt may be pushing your blood pressure up.

Also Check for “White Coat Hypertension” and “Masked Hypertension”

There are also conditions like “masked hypertension,” where your blood pressure is normal at the clinic but high at home, and, conversely, “white coat hypertension,” where it goes up at the clinic.

Recording your numbers every morning and evening with a home blood pressure monitor is the first step to getting an accurate picture.

If you show your notebook or app screen at your appointments, it will be easier for your doctor to adjust your medication.

Never cut back on or stop your medication on your own because “it isn’t working”; your blood pressure could rise suddenly and lead to a stroke or heart disease.

The Reality: “Hidden Salt” Is Getting in the Way of Lowering Your Blood Pressure

The first thing you hear about diet for high blood pressure is “cut back on salt,” but many people who aren’t succeeding at cutting salt are overlooking “hidden salt”.

Even if you say “I don’t use salt in my cooking,” when you add up the salt in processed foods, eating out, and condiments, the total is surprisingly high.

When you take in too much salt, your body holds on to water to dilute the salt concentration in your blood, so the very amount of water flowing through the hose increases.

Typical Sources of Hidden Salt

The average Japanese person is said to take in about 10 g of salt a day, while dietary guidelines for high blood pressure set a target of less than 6 g.

That works out to nearly double the salt.

Tips for Cutting Salt You Can Start Today

It’s easier to stick with if you think of cutting salt not as “putting up with bland food” but as “adding flavor from things other than salt.”

Your taste buds gradually get used to lighter flavors as you keep at it, so think of the first few weeks as the make-or-break period.

If you share meals with your family, it’s easier to keep going if you start with tweaks that don’t require changing everyone’s seasoning, such as using less condiment on your own portion after serving.

Eating Habits Other Than Salt That Raise Blood Pressure

In fact, salt isn’t the only problem.

One eating habit that’s been getting attention in recent years for getting in the way of improving high blood pressure is eating too many refined carbs (white rice, sugar, sweets).

Eating large amounts of carbs advances insulin resistance, which promotes the reabsorption of sodium (salt) in the kidneys and makes blood pressure more likely to rise.

What’s more, chronic high blood sugar and high insulin levels cause inflammation and stiffening of the blood vessels, and as the vessels lose their flexibility, blood pressure rises even further, creating a vicious cycle.

Just as a once-soft hose becomes rock-hard with age, stiffened blood vessels can no longer release the pressure.

A Disrupted Gut Environment Can Also Cause High Blood Pressure

You might be thinking, “High blood pressure and gut health? Is there really a connection?” But this is a topic attracting attention in the latest research.

Several papers have reported research findings that an imbalance of gut bacteria (dysbiosis) raises the risk of high blood pressure.

The Surprising Link Between Your Gut and Blood Pressure

When gut bacteria ferment dietary fiber, they produce “short-chain fatty acids (SCFAs).”

These short-chain fatty acids work to widen blood vessels and help the kidneys excrete sodium.

But when you keep eating a diet high in processed foods, sugar, and refined carbs and low in fiber, the balance of your gut bacteria breaks down and SCFA production decreases.

As a result, your body becomes one whose blood pressure is harder to bring down.

You could say gut bacteria are like “little factories” that take in fiber as feed and make substances that are kind to your blood vessels.

If the feed doesn’t reach the factories, the substances that protect your blood vessels stop being made.

Getting fiber from vegetables, seaweed, mushrooms, beans, mochi mugi (sticky barley), and similar foods, and combining them with fermented foods like natto (fermented soybeans) and yogurt, is the shortcut to keeping your gut’s factories healthy.

Alcohol and Blood Pressure

Alcohol also has a big effect on blood pressure.

A small amount of alcohol temporarily widens blood vessels, but it’s known that habitual drinking stimulates the sympathetic nervous system and keeps blood pressure elevated.

Sleep and Stress Also Affect Blood Pressure

When lack of sleep or heavy stress continues, the sympathetic nervous system, which puts your body on alert, takes over, your blood vessels constrict, and your blood pressure becomes more likely to rise.

Simply putting your phone away before bed to protect your sleep time, or taking a long soak in the bath, can help ease your body’s tension.

If you snore loudly or feel very sleepy during the day, ask your doctor whether sleep apnea might be hiding behind it.

Which Eating Patterns Are Effective for Improving Blood Pressure?

So what kind of diet is effective for improving blood pressure?

The eating pattern known worldwide as having the strongest evidence is the “DASH diet” (Dietary Approaches to Stop Hypertension).

The Basic Structure of the DASH Diet

Research has reported that following the DASH diet lowers systolic blood pressure by about 8 to 14 mmHg.

It’s even said to match the effect of one type of blood pressure medication, which reminds me just how powerful food can be.

Potassium Is a “Natural Blood Pressure Reducer”

Especially important in the DASH diet is getting enough potassium.

Potassium helps your body excrete sodium, so it can be expected to lower blood pressure naturally.

Think of it as a “mover” that carries excess salt out of your body.

Foods rich in potassium include avocados, spinach, sweet potatoes, bananas, and beans.

However, if your kidney function is reduced, you need to be careful not to get too much potassium, so add it while consulting your doctor.

Some blood pressure medications also affect potassium levels, so always check with your doctor before taking potassium supplements.

A Sample DASH Menu Using Japanese Food

The DASH diet is a Western eating pattern, but by making the most of Japanese food’s strengths, it becomes easier to bring to the Japanese table.

Simply cutting back a little on how often you have tsukemono (Japanese pickles), tsukudani (foods simmered in soy sauce and sugar), and miso soup can keep salt, the weak point of Japanese food, in check.

Fruit is rich in potassium, but turning it into sweet juice leads to too much sugar, so it’s best to eat it fresh whenever possible.

Remember that the DASH diet isn’t about “lowering blood pressure with any single food”; it’s an approach that protects your blood vessels through the balance of your whole diet.

“How You Eat” and Meal Timing: What People With Resistant Hypertension Should Review

Just as much as what you eat, “how you eat” and “when you eat” also affect blood pressure.

Here are some points about how you eat that are worth reviewing before you change what’s in your meals.

Stop Eating Fast and Overeating

When you eat fast, you overeat before the signal that you’re full reaches your brain, which makes your weight and blood sugar more likely to rise.

Just putting your chopsticks down after each bite, chewing well, and taking about 20 minutes to eat will naturally bring your portions down.

Losing weight lightens the load on your heart and blood vessels, so for people with obesity, it’s a big help in lowering blood pressure.

Avoid Late-Night Meals

When you eat right before bed, your body can’t rest because it’s busy digesting, your sleep quality drops, and this tends to affect your blood pressure the next morning.

Aim to finish dinner at least 3 hours before bed, and on days when it gets late, keep the meal light.

Securing time without food in the evening also leads directly to building in a comfortable fasting period.

How to Choose When Eating Out or at Convenience Stores

Pair Your Home Blood Pressure Readings With a Food Log

If you jot down a line about what you ate that day alongside your morning and evening blood pressure, you’ll start to see your own patterns, such as “it’s high the morning after eating out.”

Blood pressure also tends to change with the seasons and temperature, and it’s known to read higher in winter.

Instead of getting excited or discouraged over a single day’s number, looking at changes in your average over 1 to 2 weeks will take the pressure off.

This record also becomes important information when your doctor decides whether to adjust your medication or your lifestyle habits.

Get Moving Along With Changing Your Diet

Something to add alongside reviewing your diet is light aerobic exercise such as walking.

Moving your body helps your blood vessels regain their flexibility and helps insulin work better, so it gives a boost to the benefits of improving your diet.

Even just walking around your neighborhood for 10 to 15 minutes after a meal helps curb a sharp blood sugar spike.

However, exercises where you hold your breath, such as lifting heavy objects, can raise blood pressure suddenly, so talk to your doctor before you start.

FAQ: Resistant Hypertension and Improving Eating Habits

Balance Your Blood Pressure at the Root Through Eating Habits, and Aim for a Body That Doesn’t Over-Rely on Medication

If your blood pressure isn’t stable even though you’re taking blood pressure medication, the first thing to review is “the quality of your diet.”

By reviewing not just salt but also the quality of your carbs, your gut environment, and even the timing of your meals, there are cases where blood pressure that wouldn’t budge with medication alone improves.

Knowing about the dangers of metabolic syndrome, where high blood pressure, obesity, and blood sugar problems set off a chain reaction will boost your motivation to improve even further.

3 Steps to Better Blood Pressure You Can Start Today

Personally, since making fasting a habit, my body feels better overall, and I have the sense that my blood pressure numbers have become more stable too.

I remember being amazed that simply narrowing my eating window could make such a difference.

However, if you take blood pressure medication and suddenly eat much less, your blood pressure may drop too far and cause dizziness or lightheadedness, so don’t let your guard down.

When you start fasting, it’s safest to tell your doctor and try a short fasting period of about 12 hours while checking your blood pressure at home.

Even when you build in fasting periods, if what you eat during your eating window is all processed or salty food, you can’t expect much improvement in your blood pressure.

Think of continuing fasting together with a low-salt, vegetable-focused diet as the fastest way to give your blood vessels a rest.

Even if your blood pressure starts to come down, remember that whether to reduce your medication is always for your doctor to decide.

Taking the perspective that resistant hypertension isn’t “something to manage with medication alone” but “something you can fundamentally rethink through your eating habits, alongside your medication” is the first step toward improvement.

Start by changing today’s meals, little by little.

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