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    Everything these days is rising: temperatures, the cost of living, the number of social media influencers, and with them, possibly your blood pressure. 

    Maybe at your last physical, your numbers were a little higher than usual, and because high blood pressure runs in your family, all the ups and downs over the past few years have you worried.

    Blood pressure on the rise? Join the movement toward better health with intermittent fasting. Discover the potential to bring those numbers back down. Your heart will thank you!

    You’ve heard about some of the possible health benefits of intermittent fasting and may have some questions like? — does fasting lower blood pressure, or could it help blood pressure stay within normal limits? Or does fasting raise blood pressure? Just how can not eating affect your blood pressure? If I already have high or low blood pressure, is intermittent fasting safe for me?

    You’re in luck! You came to the perfect place to find out about all things fasting and blood pressure.

    Key takeaways

    • If you are already taking medication for blood pressure, check in with your doctor before starting an intermittent fasting blood pressure plan.  
    • High blood pressure makes your heart work harder, possibly causing worsening heart health over time.
    • Intermittent fasting could be a good fit for you if you are looking to lower blood pressure or prevent it from getting high. 
    • Eating a diet high in fiber and low in sodium and saturated fats is the best nutrition to support a healthy heart and healthy blood pressure.

    Fasting’s effect on your blood pressure and heart health

    Before we get into how can fasting lower blood pressure, let’s go over some blood pressure basics.

    What is blood pressure anyway? 

    Your heart pumps blood through your body to provide oxygen, energy, and nutrients to your cells. On the return flow, it removes cellular waste and takes it to the organs that get rid of it. The force of your blood against the walls of your veins is your blood pressure.

    How does blood pressure work? 

    Blood pressure is represented by two numbers, like this: 120/80. The first number (120) is your systolic blood pressure and measures the maximum pressure during a heartbeat. The second number (80) is your diastolic blood pressure and measures the minimum pressure in your arteries between beats.

    A normal blood pressure falls between 90/60–120/80. There are a range of factors that can influence blood pressure ranges including age, gender, and different medical guidelines. Being consistently either above or below this range can lead to serious complications such as stroke, heart disease, kidney disease, and circulation problems.[1] 

    What’s the difference between high and low blood pressure?

    High blood pressure, or hypertension, is when blood is forcefully pumped through the arteries. Over time, this can lead to damaged blood vessels.[2] You can kind of think of it like beach erosion from the force of storm waves.

    When blood needs to be pumped with extra force, the heart has to work harder. There is some good in working your heart, like with exercise, but with hypertension, the heart gets overworked, increasing the risk of heart failure. 

    Low blood pressure, or hypotension, is a sign that the heart is not pumping well. This can cause poor blood flow to major organs and lead to symptoms like dizziness and fainting.[3]

    What affects blood pressure?

    Weight 

    Excess body fat has long been shown to have an effect on blood pressure.[4] It can increase resistance to blood flow in the vessels. Increased fat tissue surrounding the blood vessels — and the inflammation and insulin resistance that may come with excess body fat — can also hinder vasodilation (the flexibility of the blood vessels), making it harder for blood to flow. This resistance in blood flow forces the heart to pump harder. 

    Exercise

    During exercise, muscles need more oxygen and energy, so blood pressure increases to get them what they need. Over time, with consistent physical activity, the heart becomes stronger and more efficient at pumping.[5] The blood vessels also respond by becoming more flexible and less resistant to changes in blood volume. Both changes lead to improved blood pressure numbers.[5] 

    Sleep

    Poor sleep and sleep disorders can affect blood pressure. Sleep disorders like obstructive sleep apnea mean the body is not getting enough oxygen throughout the night. Blood pressure will increase while you’re sleeping to try to get more oxygen to organs that are trying to recover from the day.[6] 

    Improvements in all these factors are potential intermittent fasting benefits. If all of this sounds good to you, learn more about them and the different intermittent fasting schedules in our breakdown on intermittent fasting for beginners; then take our SIMPLE quiz to match with your best schedule.

    Hydration

    Chronic dehydration can lead to hypertension.[7] When you’re not drinking enough water, blood volume is low, and the heart has to pump harder to work with the blood it does have. Dehydration can also make the blood thicker, making it more resistant to flow (think trying to pour a smoothie vs. a glass of juice). 

    Fasting and blood pressure 

    Every bite of this heart-y breakfast gets us thinking: Did you know that intermittent fasting might be a key to managing blood pressure, even without weight loss?

    Let’s get to our big question — does intermittent fasting lower blood pressure directly?

    It was thought that the central connection between how fasting lowers blood pressure was weight loss and other metabolic changes. However, a recent study has shown that fasting to lower blood pressure in men with pre-diabetes— even without weight loss — is possible![8]

    If you want to find out whether or not does not eating during certain windows, to lower your  blood pressure is for you, get the green light from your doctor first, then use our guide to put together an intermittent fasting meal plan to help you eat well, maintain your weight, and potentially get your blood pressure down!

    Other fasting benefits for your cardiovascular system

    We now know that healthy blood pressure is key for a healthy heart and that fasting can help you maintain it, but fasting does more for your heart than just lowering blood pressure, like:

    • Weight loss — specifically fat loss, and especially around the belly. Belly fat is a good indicator of visceral fat (fat around the major internal organs).[9] Reducing body fat makes the heart’s job a little easier.[10]
    • Reducing LDL cholesterol. LDL is also known as “bad” cholesterol, and that increases your risk for atherosclerosis (a build-up of fats and cholesterol in the blood vessels) and heart disease.[11]
    • Increased insulin sensitivity. Intermittent fasting helps the body switch energy sources from carbohydrates to fat. That “metabolic switch” helps the body use insulin more efficiently, reducing the risk of type 2 diabetes.[12] 

    All of these factors lead to a healthier, less stressed heart. 

    Can you strengthen your heart by fasting?

    There’s no evidence that directly shows you can strengthen your heart by intermittent fasting (that tends to be exercise’s domain), but, as we’ve seen, there’s plenty that shows how fasting can support a healthy heart.  

    You can increase this beneficial effect on heart health even more by eating heart-healthy foods, like berries, whole grains, leafy green veggies, and oily fish, during your eating window. 

    Should you follow an intermittent fasting schedule? 

    If you’re interested in fasting for blood pressure or any of the other benefits we mentioned, chat with your doctor about it first, to make sure it’s safe for you.  

    The best way to know if intermittent fasting is a good fit for you is to give it a try! Take our SIMPLE quiz to get started with a fasting schedule that suits your needs, and we’ll hold your hand while you get comfy. Our in-app articles will show you the ropes so you can feel confident, start making progress, and not get thrown off track by any rookie intermittent fasting mistakes!

    What if I have hypotension? 

    If you have hypotension (i.e., low blood pressure), fasting may not be the right fit for you. Talk about any plans to change your diet with your doctor before you start anything new.

    Even with normal blood pressure, some intermittent fasting side effects can look similar to hypotension symptoms, such as dizziness, headaches, and fainting. If you try fasting, listen to your body and pay attention to any signals it gives you. If side effects like these don’t go away after a few days, go see your doctor and get them checked out.

    Tips on starting intermittent fasting for better blood pressure

    Gathering around the table, sharing heart-healthy delights, and reimagining our food choices with intermittent fasting! Who said eating for better blood pressure couldn’t be a delightful communal experience?

    Plan your meals

    Knowing what to eat during intermittent fasting can help you optimize the benefits while limiting the risks.

    Eat more heart-healthy foods

    Include generous amounts of fruits, vegetables, whole grains, and healthy fat (e.g., avocado, fatty fish, olive oil, nuts and seeds). Heart-healthy foods are considered so because they contain minerals and electrolytes like magnesium, potassium, and calcium. They are essential to supporting a healthy and well-functioning heart.

    Lower your salt intake

    Sodium is the fluid balance mineral. Too much, and your body will hold onto water, increasing your blood volume. Too high a blood volume can put extra pressure on your organs and blood vessels.[13]

    Lower your salt intake by eating more fresh foods and avoiding adding salt during cooking or at the table.

    Who should avoid intermittent fasting? 

    Intermittent fasting is generally safe for healthy adults, but for some people, fasting carries a higher risk. Check with your doctor before starting if:

    • you’re pregnant, breastfeeding, or trying to conceive
    • you have a body mass index (BMI) < 18.5
    • you have (or are at risk of having) an eating disorder or have a history of one
    • You have type 1 diabetes
    • you take prescription medications 
    • you’re under 18 years old, or 80 years old or more
    • you’re extremely active

    SIMPLE’s expert opinion and final thoughts 

    Hypertension is often known as “the silent killer” because the damage can happen without you knowing. While we need more research on intermittent fasting and its direct relationship to blood pressure, there are some positives already in play. 

    Intermittent fasting has been proven to improve metabolic health markers like cholesterol and blood sugar levels and can also help with weight loss.[14,15] All of these support a healthy blood pressure. 

    If you’re ready to give fasting to lower blood pressure a try — and it’s safe for you to do so — take our SIMPLE quiz to get started! 

    Frequently asked questions about what to eat when fasting

    How long do you have to fast to reduce blood pressure? 

    Fasting’s impact on blood pressure varies among individuals and depends on factors like the type and duration of fasting. Short-term fasting may lead to temporary blood pressure reduction.[16] However, individual responses differ, and consistency in dietary and lifestyle changes is crucial. Always consult a healthcare provider before starting any fasting regimen, especially if you have existing medical conditions or take medications.

    Is fasting the quickest way to lower blood pressure? 

    Fasting is not the quickest way to lower blood pressure and may not be safe for you if you are on blood pressure medications. Talk to your doctor before trying fasting or making any significant changes to your diet.

    Does caffeine raise blood pressure? 

    It is possible for caffeine to raise blood pressure [17], but everyone is different. If it does, usually the increase is short term. If you’re fasting for blood pressure reasons, talk to your doctor about whether you need to limit caffeine and read our guide to learn what you can drink while intermittent fasting.

    Does drinking water lower blood pressure? 

    Drinking water can support lower blood pressure.[7] Proper hydration helps support healthy blood volume and keeps your blood flowing. Drinking too much water can also be risky. Be sure to check with your doctor or dietitian about how much is enough for you.

    What time of the day is blood pressure highest? 

    The time of day that blood pressure is the highest is usually midday or when you are most active.[18] Blood pressure should drop to its lowest while you are resting at night. Having uncontrolled hypertension or poor sleep quality can affect that.

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