The ketogenic diet is known as a high-fat, low-carbohydrate diet that can incorporate a lot of meat and cheese, not to mention (high-quality) salt.
So how is it that people are reporting healthy blood pressure levels and even an improvement in blood pressure on a keto diet?
Aren’t these foods supposed to be terrible for you?
High blood pressure is a risk factor for a handful of serious conditions related to your heart, brain, and kidneys. Learning how to manage and prevent high blood pressure is an essential part of keeping your whole body happy and healthy.
But there’s a right way and a wrong way to use the keto diet to improve your blood pressure.
If you’re wondering what the best eating plan is for optimal blood pressure, read on to learn how food and lifestyle affect this crucial aspect of your health.
As your heart beats, it pumps blood that circulates throughout your body.
This process is what pumps oxygen and nutrients to every tissue and organ in your body, making sure that everything is running properly.
Your blood travels throughout your body in blood vessels. And the vessels moving blood away from your heart and to the rest of your body are called arteries.
As your blood runs through your arteries, it naturally pushes against the sides of them; this exerts a pressure on your arteries which is called your blood pressure.
Your blood pressure is a combination of the force and rate of your heartbeat, and the elasticity of the walls of your arteries.
When your heart beats, it contracts and relaxes in a rhythmic manner.
This ebb and flow of contraction and relaxation is how blood keeps pumping through your body. Each time your heart contracts it raises the pressure of your blood a bit, and when it relaxes, it lowers it a bit.
These two rhythms of the heart are measured to determine your overall blood pressure. They’re called:
- Systolic blood pressure: Taken while the heart is contracting and pumping blood into your blood vessels
- Diastolic blood pressure: Taken while the heart is relaxing and refilling with blood[*]
Blood pressure is measured in units called millimeters of mercury (mmHg), and represents both your systolic and diastolic blood pressure.
Results are read as: systolic/diastolic mm Hg.
For example, if your systolic blood pressure is 138 and diastolic is 85 it would read; 138/95 mm Hg.
Below is a breakdown from the American Heart Association of what blood pressure values mean in terms of your risk for high blood pressure (also called hypertension).
Healthy blood pressure is a systolic reading of 120 mm Hg or less, and a diastolic reading of 80 mm Hg or less.
When your blood pressure becomes slightly elevated, you are at risk for developing high blood pressure; this is a good time to implement diet and lifestyle prevention.
High blood pressure is broken down into stage 1 and stage 2, these are the stages where medication is usually prescribed.
If your reading is higher than 180/120, this is considered a hypertensive crisis. At this point, you should contact your doctor immediately or go to the hospital.
You may be wondering what the big deal is with blood pressure. So your blood is moving through your body faster and a little more aggressively — what could possibly go wrong?
But there are some pretty serious risks that come with chronic high blood pressure.
Risks of High Blood Pressure
Some of the risks associated with high blood pressure include[*]:
Cardiovascular Disease (CVD): High blood pressure can cause your blood vessels (arteries) to harden due to sustained stress; this results in a thickening of the artery walls, which can decrease the blood flow to your heart while raising blood pressure even more. This combination can result in heart disease.
Heart Failure: Your heart can no longer pump enough blood and oxygen to your other organs.
Heart Attack: Blood flow to the heart is blocked, and your heart muscle begins to die due to lack of oxygen.
Stroke: High blood pressure can burst or block arteries that send blood and oxygen to your brain. A lack of oxygen to your brain is considered a stroke, and without adequate oxygen, brain cells can start to die.
Chronic Kidney Disease (CKD): Hypertension is a risk factor for CKD and is associated with a more rapid progression.
The most common way of measuring your blood pressure is using a blood pressure cuff that straps to your upper arm.
The cuffs are pretty straightforward to use; you simply strap it on to your upper arm, and follow the directions, the automatic blood pressure readers do most of the work.
However, here are some tips to make sure you’re getting an accurate reading:
- Sit still: Try to relax as much as possible, don’t exercise or drink caffeinated beverages 30 minutes before you take your measurements.
- Seating position: Make sure your back is straight and your feet are on the ground, legs uncrossed. Your arm should be supported, with your upper arm at heart level.
- Measure at consistent times: You want to get an understanding of your blood pressure over a few days, not just one reading. It’s best to measure at the same time each day to see what your fluctuations are day to day (if any).
- Take multiple readings: When measuring your blood pressure, take two or three readings at a time, a couple of minutes apart to make sure you’re getting an accurate read.
Several different lifestyle and diet factors can lead to hypertension. Here are some of the most common causes of high blood pressure:
#1 Too Much Salt (Sodium)
Sodium is an essential mineral that your body needs to function properly. It has an intimate relationship with potassium, and these two minerals work together to balance the fluid and blood volume in your body.
But problems occur when there’s an imbalanced ratio of potassium to sodium.
The Standard American Diet is very sodium-rich and much lower in potassium. This is one of the reasons that so many people in the U.S. experience high blood pressure[*][*]. It’s also why your doctor likely told you to cut down on the salt.
These two minerals are involved in an intricate dance in your body, but to put it plainly; sodium makes your body hold onto more fluid. This means a higher volume of blood and water in your body.
Under optimal circumstances, your kidneys will help your body excrete extra fluids and maintain a healthy balance. When you have too much sodium and not enough potassium, your kidneys hold on to more water.
This extra stored water increases your blood pressure (more blood means more pressure), and puts a strain on your heart, arteries, kidneys, and brain[*].
When you’re under stress, your sympathetic nervous system, also known as your “fight or flight” response is activated.
Hundreds of years ago when our hunter-gatherer ancestors were roaming around the forests looking for food, this fight or flight response served us very well.
You’re out hunting for dinner, and a hungry lion sneaks up on you out of nowhere.
In this scenario, you don’t really want to sit there and think about your options. There’s no time for thoughtful contemplation.
Instead, your sympathetic nervous system gets switched on, and you’re in fight or flight mode. Your heart starts beating faster, increasing your blood pressure, and your blood starts flowing to your arms and legs so you can bolt[*].
Unfortunately, this ancient survival adaptation is still very much in play today when more modern-day “lions” pop up. Things like traffic, unruly children, demanding bosses, work deadlines, etc.
So stress turns on your sympathetic nervous system, and your sympathetic nervous system increases your blood pressure. This is why doctors say that stress literally kills — high blood pressure from chronic stress leads to heart disease[*][*].
#3 High Levels Of Insulin (Insulin Resistance)
Insulin resistance and hypertension have a cause and effect relationship. High levels of insulin can increase the reabsorption of sodium by your kidneys.
Elevated levels of insulin can also activate your sympathetic nervous system, which drives up your blood pressure[*].
#4 Excess Fructose Consumption
Simple sugars and blood sugar both play a role in hypertension.
There is a direct correlation with the rising levels of fructose consumption in the Western world and the rise in hypertension[*].
Animal studies indicate that high fructose diets can lead to hypertension in a couple of different ways[*]:
- Fructose may upregulate sodium transporters, resulting in a higher level of sodium in the body, which raises blood pressure.
- Fructose may activate vasoconstrictors (compounds that constrict blood vessels) and inactivate vasodilators (compounds that expand blood vessels). This leads to blood vessel constriction, which increases the pressure of blood in your vessels.
- Fructose may activate your sympathetic nervous system, which stimulates an increase in blood pressure.
#5 Adrenal Disorders
Some adrenal disorders can lead to hypertension. Specifically, if your adrenals are secreting excessive amounts of the male sex hormone aldosterone, you can end up with too much sodium retention.
Smoking can increase both your heart rate and blood pressure, largely due to the nicotine found in most cigarettes.
One of the many reasons people can become so addicted to cigarettes is due to the effect they have on your nervous and vascular systems.
Nicotine increases blood pressure by increasing cardiac output (heart beats faster), while simultaneously increasing vascular resistance — this makes it harder for your blood to push through your blood vessels[*].
At the same time, nicotine activates your sympathetic nervous system, which plays its own role in waking you up and getting your blood pressure moving[*].
- Over the counter NSAIDS (nonsteroidal anti-inflammatory drugs)
- MAO inhibitors (antidepressants)
- Birth control pills
- Antidiabetic drugs
- Steroid drugs
Always consult with your health care practitioner before starting or stopping any medications.
#1 Eat Low-Carb To Manage Insulin
Cleaning up your diet can have a profound effect on your blood pressure, with the two main blood pressure culprits in your diet being sugar and salt.
Researchers performed a systematic review and meta-analysis including 14 studies with over 1000 participants to determine the role of blood sugar in the management of high blood pressure.
The results of the analysis revealed that a lower glycemic diet (a diet that keeps blood sugar low), is correlated with lower levels of blood pressure[*].
These results are not surprising given that blood sugar stimulates insulin, and insulin stimulates your kidneys to reabsorb sodium, and more sodium leads to higher blood pressure[*].
A low glycemic diet keeps your blood sugar low by limiting the amount of carbohydrates that you absorb at one time. Most low-carb diets fall into the category of low-glycemic, including the ketogenic diet.
#2 Lower Your Salt Intake To Balance Your Sodium/Potassium Ratio
The ratio of sodium and potassium in your body is a crucial factor in blood pressure control. When you retain too much sodium your fluid levels rise, increasing the volume of blood in your blood vessels and leading to hypertension[*].
To maintain this delicate balance you need to increase high potassium foods while limiting foods that contain excess sodium.
Many heavily processed foods are full of sodium for taste and preservation purposes. Focusing on a diet full of whole food options like fresh meat and vegetables will help shift this balance.
Some foods with a high potassium content include spinach, swiss chard, avocado, salmon, radishes, whey protein, and turkey[*].
#3 Decrease Fructose Intake
There’s a strong correlation between the increase in fructose consumption in the Western world and the increase in the incidence of hypertension.
Fructose consumption may increase blood pressure by increasing sodium retention, activating your sympathetic nervous system, and causing a restriction of your blood vessels[*].
Avoid foods like high fructose corn syrup, fruit juices, candy, maple syrup, and other food containing high levels of fructose to help lower your blood pressure[*].
When you exercise your heart rate increases, which will cause a short-term increase in your blood pressure.
Over the long run, however, physical activity can actually help lower your blood pressure and enhance your heart health. The exact mechanism by which exercise reduces blood pressure and risk for hypertension is not yet understood, but there are a few strong theories.
Exercise may benefit hypertension by[*]:
- Enhancing kidney health
- Increasing insulin sensitivity
- Decreasing body weight
- Increasing parasympathetic response (therefore decreasing sympathetic response)
- Reducing emotional stress
- Improving the strength of your heart
#5 Weight Loss
Being overweight or obese us a huge risk factor for high blood pressure.
Research shows that your blood pressure rises as your body weight increases, and losing even 10 pounds can have a significant effect on your blood pressure if you’re overweight or obese[*].
One of the primary complications of being overweight is metabolic syndrome, a group of symptoms that increase your risk of type 2 diabetes and heart disease.
By decreasing your body weight, you lower your risk of metabolic syndrome — and with that the risk factors for heart disease like hypertension[*].
Choosing the right foods is essential to managing your blood pressure — even if you’re on medication. And a low-carbohydrate or keto diet can help.
Here are just a few ways a low-carb diet can support healthy blood pressure:
Keto Supports Heart Health
If you have some weight to lose, cutting down on your carbs may not only help you shed pounds, but it can also support heart health[*].
Keto Balances Blood Sugar
When you’re following a keto diet, you automatically cut down on foods that cause a rise in blood sugar and insulin.
It’s Low in Sugar
While it’s true that salt can undoubtedly play a role, there’s good reason to believe that sugar may actually be more impactful on blood pressure than salt[*]
As you learned earlier, insulin can cause sodium retention and stimulate your sympathetic nervous system — ultimately leading to hypertension. By following a diet that’s low in sugar, you avoid the potential pitfalls that come with high levels of insulin in your body[*][*]. Keto is also low in fructose, which can raise blood pressure[*].
Some research even suggests that following a low-fat diet that’s high in carbs may increase your risk for high blood pressure and metabolic syndrome[*].
The Takeaway: Is a Keto Diet Good For Your Blood Pressure?
Following a healthy keto diet is a great way to help manage your blood pressure.
Keto not only keeps your insulin in check, but it helps you avoid certain foods that can increase your risk for hypertension like high fructose corn syrup and other refined carbohydrates.
One area of caution: Many keto-friendly foods also fall under the category of processed food. Make sure you’re watching your intake of processed meats, cheese, and other low-quality packaged foods that contain excessive amounts of sodium.
If you’re just starting keto, or need a little guidance on how to follow a clean keto diet check out this kickstart guide for tips and lists of foods to eat and avoid.