According to the CDC, almost half of all adults in the US have high blood pressure, also known as hypertension. Excess body weight is one of many factors that increase the risk of developing hypertension. Because of that, losing weight is often one of the recommendations for the treatment of hypertension. But how does losing weight lower blood pressure? And how much weight do you have to lose to see a change in your blood pressure?
Hypertension: What Is It?
Hypertension is diagnosed when your blood pressure is consistently higher than normal. Blood pressure refers to the pressure at which your blood pushes against the walls of your arteries (the vessels carrying your blood away from your heart and to the rest of your body). High blood pressure is a problem because over time it increases the risk of more serious problems like having a heart attack or stroke.
When measuring blood pressure, there are two numbers:
Systolic blood pressure is the top number in a blood pressure reading, and represents the pressure in your arteries when your heart beats.
Diastolic blood pressure is the pressure in your arteries when your heart relaxes in
between beats. It is recorded as the bottom number in a blood pressure reading.
The most recent guidelines from the American College of Cardiology and the American Heart Association say that a diagnosis of hypertension should be made when your systolic blood pressure is 130 mmHg or greater OR your diastolic blood pressure is 80 mmHg or greater (based on an average of ≥ 2 careful readings obtained on ≥ 2 separate occasions).
Hypertension: What Causes It?
There are two types of hypertension – primary and secondary. Primary hypertension is the most common type, and it is caused by a combination of genetics and environmental factors. Secondary hypertension is less common and the result of a medical condition or medication.
There are several risk factors for the development of essential hypertension. Some of them are within our control while others are not. Modifiable risk factors include a high-salt diet, physical inactivity, excess body weight (especially weight in the midsection), tobacco use, and alcohol use. Non-modifiable risk factors that increase hypertension risk include family history/genetics, age, male gender, and race.
Many chronic diseases, such as obstructive sleep apnea, high cholesterol, and diabetes mellitus, also increase the risk of hypertension. While these may be out of our control, they can often be improved with healthy eating habits, regular physical activity, and weight loss.
How Are Obesity and Hypertension Related?
Excess body weight is considered a major risk factor for the development of high blood pressure with studies showing a correlation between increasing body weight and increasing blood pressure. The reasons for this are still being investigated, but likely involve a combination of the following:
- Excess body weight increases central nervous system activity through elevated insulin and leptin levels. This increase in the activity of the central nervous system increases blood pressure.
- Excess body weight increases sodium reabsorption in the kidneys, which increases blood volume and the pressure on the walls of the arteries.
- Inflammation and abnormal function of the arteries is associated with excess body weight. This leads to hardening and narrowing of the arteries, increasing blood pressure.
The good news is that science supports that losing weight or maintaining a healthy body weight can be effective for blood pressure management. Weight loss is usually the first treatment recommendation when high blood pressure is diagnosed, and can also prevent the progression to higher blood pressure readings over time.
High Blood Pressure Treatments
The goal of hypertension treatment is to reduce blood pressure in order to reduce the risk of serious conditions like heart attack and stroke. There are a number of things you can do to improve your blood pressure, including:
- Eat a heart-healthy diet with less salt – Research shows that a diet rich in fruits, vegetables, whole grains, and lean protein with less saturated fat can reduce blood pressure and the risk for heart disease. Additionally, lowering salt consumption by at least 1000 mg per day can help to reduce blood pressure.
- Participate in regular physical activity – Regular physical activity helps with weight management and lowering blood pressure, regardless of whether or not you lose weight.
- Lose weight if you have excess body weight – One of the best things you can do to improve your blood pressure is to lose weight. You can expect to lower your blood pressure by about 1 point for each 2.2 pounds of weight you lose.
- Limit alcohol consumption – Men should aim to consume no more than 2 standard drinks per day and women no more than 1 standard drink per day. A standard drink is 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of distilled spirits. Limiting alcohol consumption is also helpful in weight management, so it can have a positive effect on blood pressure in this way as well.
- Quit smoking – If you smoke or use tobacco products, quitting alone can reduce blood pressure.
- Medications – If your blood pressure is significantly elevated, you are at high risk for heart disease, or your blood pressure does not improve with a trial of healthier habits and weight loss, your doctor may recommend a medication to lower your blood pressure. Some classes of medications used to treat hypertension include:
- Angiotensin-converting enzyme (ACE) inhibitors
- Angiotensin II receptor blockers (ARBs)
- Calcium channel blockers
- Beta blockers
Lower Blood Pressure with Weight Loss & Lifestyle Changes
The combination of lifestyle changes and weight loss can have a big impact on lowering your blood pressure, ultimately reducing the number of medications you take and the risk of serious conditions like heart attack and stroke. While there is no best diet for weight loss, there have been studies to suggest that eating a diet high in fruits, vegetables, whole grains, and lean protein and low in saturated fat, salt, and alcohol work well for both weight loss and blood pressure reduction. One such diet is the Dietary Approaches to Stop Hypertension (DASH) diet. But any healthy eating plan that reduces calories can be an effective approach. And doing this in combination with physical activity can have even greater benefits. Both aerobic and resistance training and high and low intensity exercise have all been shown to provide benefits for weight loss and blood pressure.
Making these healthful lifestyle changes can lower your blood pressure and reduce your risk of heart disease independent of weight loss. However, when you also achieve weight loss, the benefits are even greater. And it doesn’t have to be much – studies show that losing even 5% of your body weight can significantly lower your blood pressure.