Fasting and Feasting for Lower Blood Pressure
How diet and intermittent fasting fights back against hypertension
High blood pressure, or hypertension, is the leading modifiable risk factor for death worldwide. In Canada, medication is commonly prescribed to the one in four Canadians who suffer from high blood pressure. We explore the combined roles of intermittent fasting, dietary changes, and natural health products in changing that reality.
When we talk about fasting, most people assume we’re talking about it in relation to managing weight. But the surprising news is that research is beginning to show other health benefits of a systematic fasting regimen.
What’s new about fasting?
How long do you usually go from your last bite of food at night to your first bite the next day? In my experience, many people tend to go between eight and 10 hours.
When you occasionally push that “no food” window closer to 16 hours, though, you enter the realm of what has come to be known as intermittent fasting. The interest surrounding intermittent fasting and human health is increasing as research into its benefits continues to accumulate.
When we engage in varying degrees of intermittent fasting, several physiological changes relevant to blood pressure take place. Scientists believe that one such change is the increased production of a protein known as BDNF, or brain-derived neurotrophic factor.
BDNF is known to stimulate brain cells to release a compound known as acetylcholine, which has two blood pressure-related effects on the body:
- It reduces heart rate.
- It expands the blood vessels.
In concert, these changes contribute to lowering blood pressure as part of the body’s parasympathetic or “relaxation” response in the nervous system.
For this reason, researchers are increasingly intrigued by intermittent fasting as a potential mechanism to prevent hypertension in the broader population. A recent study of 60 people living with hypertension found that intermittent fasting had the potential to contribute to lower blood pressure scores throughout the day.
While this study alone does not provide indisputable evidence that fasting should be a primary treatment option for hypertension, it contributes valuable insight into what will surely continue to be a closely followed area of study.
Did you know?
High blood pressure, also known as hypertension, is the leading modifiable risk factor for death worldwide. Approximately one in four Canadians are living with high blood pressure, which is commonly referred to as the “silent killer,” both for its pervasiveness and the fact that it is accompanied by no obvious signs or symptoms.
What is blood pressure?
Blood pressure, just like it sounds, is a measure of how forcefully the blood flowing through the body presses against the veins and arteries that carry it. When this force remains chronically high, the blood vessels are at increased risk of damage, which contributes to an increased risk of death and disease.
A healthy blood pressure reading is considered 120/80, but what do those numbers actually mean?
Systolic blood pressure
The top number, known as systolic blood pressure, is a measure of the force exerted by blood when the muscles of the heart are contracting (beating).
Diastolic blood pressure
The bottom number, known as diastolic blood pressure, is a measure of the force exerted by blood when the muscles of the heart are relaxing (between beats).
When is it hypertension?
Although it’s up to a medical professional to formally diagnose hypertension, generally a blood pressure reading creeping toward 140/90 will be enough to get you there.
Causes of high blood pressure
High blood pressure is caused by several factors, including genetics, stress, and dietary choices. Excessive sodium intake, which is a massive problem in North America, is responsible for nearly one in three cases of hypertension.
Sodium in the Canadian diet
Given these startling figures, it should come as no surprise that sodium reduction is a key step toward preventing and managing hypertension.
Check out this list of the Top 6 Sodium Culprits according to Health Canada.
Fight back with potassium
Sufficient dietary potassium is important in preventing and managing hypertension, because it counters the effect of excess sodium intake on blood pressure. Make some of these six very high-potassium foods a regular part of your diet:
- lentils
- avocado
- banana
- pumpkin seeds
- sweet potato
- Swiss chard
Taking charge against hypertension
Dietary modification, natural supplementation, and novel approaches such as intermittent fasting all have potentially important roles to play in improving human health and in the prevention and management of conditions such as high blood pressure.
The supervision and advice of your health care professional should always be respected. High blood pressure is a serious health concern, and in some individuals, medication may be necessary for either the short or long term to reduce the risk of negative health consequences.
Here are a few things to consider when deciding to on a fasting regimen.
The natural route
Given that blood pressure-reducing medications are among the top five most frequently prescribed in Canada, it should come as no surprise that Canadians are interested in alternative or complementary means of blood pressure management.
Dietary changes and intermittent fasting are both promising options, and many people also turn to natural health products as the third prong in their fight against hypertension.
- Cod liver oil is known for its potent anti-inflammatory effects due to high omega-3 content.
- Garlic contains protective organic sulphur-based compounds not found in many other foods.
- Coenzyme Q10 is a naturally occurring coenzyme with potential cardiovascular benefits.
A version of this article was published in the February 2020 issue of alive Canada with the title “Fasting and Feasting for Lower Blood Pressure.”
Andy is a private practice dietitian and 11x published author from Toronto, Canada. He combines his love for one on one interaction with a broader passion to be involved in content creation via his writing and social media use. Having been a generalist early in this career, Andy has spent the last several years focusing on the fatty liver space given the broad prevalence and significant health implications of this increasingly common condition.
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