This article is the third and final installment in our series on blood pressure management. The July-August issue of Food Insight featured Part I, “Dietary Approaches to Stop Hypertension—A Little DASH Will Do,” which discussed the importance of the DASH Diet for managing blood pressure. Part II, “Potassium: Milligrams Can Help Manage Millimeters of Mercury,” appeared in the October issue and focused on the role of potassium in a heart-healthy diet. Part III will examine other evidence-based diet and lifestyle approaches to managing blood pressure.
What is Hypertension? Classification and Explanation of the Range of Blood Pressure
The first step in managing blood pressure is getting it checked. Knowing your numbers is an essential component to good health. Blood pressure is expressed with two numbers in millimeters of mercury (mmHg), systolic over diastolic pressures. But what do these numbers mean?
- Systolic pressure (the top number in a blood pressure reading) denotes the force that blood exerts on the arteries as the heart muscle contracts.
- Diastolic pressure (the bottom number in a blood pressure reading) is the force that blood puts on the arteries between contractions when the heart relaxes. Diastolic pressure is always lower than the systolic pressure.
Every individual falls into one of four blood pressure classifications (low, normal, moderate, or high).
- Low blood pressure is the least discussed of the four categories. Nonetheless, it is a condition that should be monitored carefully.
- Normal blood pressure is defined by an average reading of 120/80 mmHg or less.
- Moderate blood pressure levels occur between 120-139 mmHg systolic pressure and 80-89 mmHg of diastolic pressure. This may also be referred to as prehypertension.
- High blood pressure is indicated with an average reading at or above 140 mmHg of systolic pressure or equal to and above 90 mmHg of diastolic pressure. Chronic high blood pressure is known as hypertension and can be further classified into three stages (Stage 1, Stage 2, or Hypertensive crisis)
Why Understand Hypertension? Cardiovascular Disease Risk—Achieving Health through Knowledge and Action
High blood pressure is a condition that affects 67 million Americans according to recent statistics from the Centers for Disease Control and Prevention (CDC). In other words, almost 1 in 3 US adults has high blood pressure. Unfortunately, more than 20% of those with high blood pressure are not aware that they are living with the condition. Being unaware or neglecting to control high blood pressure can negatively impact health. Among the most severe effects of failing to control high blood pressure are increased risk for heart disease and stroke, kidney damage, and loss of vision.
Clearly, not only knowing your numbers, but actively managing blood pressure is something to take seriously. The good news is that there are a variety of ways this can be done and many can begin today. The National Heart, Lung and Blood Institute (NHLBI) has published seven sets of clinical practice guidelines related to high blood pressure management dating back to 1976. The eighth set of guidelines is currently under development and due to be released early in 2013. These guidelines, otherwise known as the Joint National Committee for the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC), are primarily established for use by health professionals.
However, some of the information within these guidelines can be very beneficial to consumers. For example, did you know that there are five different lifestyle modifications that can help improve blood pressure? See the list below for more information on the actions you can begin taking today.
1. Weight Loss
a. Maintaining a healthy weight (BMI 18.5-24.9) helps maintain appropriate blood pressure. To find out your BMI, use NHLBI’s BMI calculator. If you are overweight (BMI ≥25) or obese (BMI ≥30), losing weight can reduce systolic blood pressure.
2. Following the DASH (Dietary Approaches to Stop Hypertension) diet
a. Adhering to a DASH-style eating plan can also lower systolic blood pressure. The DASH diet encourages consumption of fruits, vegetables, fat-free or low-fat milk and milk products, whole grains, lean meats (such as fish and skinless poultry), and nuts—making this diet rich in potassium, magnesium, calcium, fiber, and protein. Rather than focusing on the effects of individual nutrients, the DASH diet illustrates the combined positive effect that dietary patterns have on blood pressure and overall health.
3. Reducing sodium consumption
a. The average American consumes more than 3400 mg of sodium per day. The 2010 Dietary Guidelines recommend consuming no more than 2300 mg of sodium per day and specific populations are recommended to further reduce consumption to 1500 mg per day. While the impact of sodium reduction on blood pressure can vary between individuals, reducing sodium in the diet can be an important part of an effective blood pressure management strategy.
4. Physical activity
a. Being physically active is a critical component of good health. There are many benefits associated with leading an active lifestyle and one of the most important is maintaining proper blood pressure. Including 30 minutes of aerobic physical activity into a daily routine can help reduce systolic blood pressure.
5. Moderation of alcohol consumption
a. It may come as no surprise that limiting the intake of alcohol can have a positive effect on health, but did you know that it can help lower blood pressure as well? Lower blood pressure can be achieved by following recommendations to consume no more than two drinks per day for males and one drink per day for females or lighter weight individuals.
The Final Numbers
Blood pressure can be a confusing topic to comprehend and a frustrating one to manage. It’s been deemed the “silent killer” because its effects are generally not outwardly apparent and this may contribute to the tendency of many to leave high blood pressure uncontrolled. Of the 67 million Americans who have high blood pressure, 53 million are aware of the condition—about 4 out of 5. Of those 53 million, 47 million are being treated for the condition—or roughly 7 out of 8. Of the 47 million being treated, only 31 million have the condition under control (systolic under 120 mm Hg and diastolic under 80 mm Hg)—or nearly 2 in 3.
These statistics may not sound alarming, but consider this—more than half of the population with high blood pressure, don’t have it under control. Additionally, more than 40% of those who know they have high blood pressure have yet to get it under control.
Blood pressure reduction is a major public health problem and one that is critical to the health of our nation. The answer to the dilemma may be more readily available than we think. Experts agree that a key strategy to effective blood pressure reduction involves a comprehensive approach—one that focuses on more than just one element known to positively affect blood pressure. While the impact of one lifestyle modification can be impressive, addressing multiple lifestyle modifications is likely to be the most successful route to achieving desirable blood pressure levels.