DASH Diet For Dummies. Sarah Samaan

to your tender blood vessels.

      The human body is built to be resilient, but over time, the nonstop strain of high blood pressure can cause the following:

       Abnormal thickening and stiffness of the heart muscle, which can lead to heart failure

       Microscopic tears, stiffening, and scarring in the arteries of the heart and brain, raising the risk for heart attack, stroke, and dementia

       Irregularity of the heart rhythm, which may also raise the risk for stroke

       Damage to the blood vessels that feed the kidneys, leading to kidney failure and, in severe cases, dialysis

       Weaknesses in the walls of the blood vessels of the eyes, causing blurry vision or even blindness

      

Some of these problems can be stabilized or even reversed if they’re caught early. But why put yourself in harm’s way? Don’t ignore your high blood pressure. Follow the treatments prescribed by your doctor. High blood pressure can almost always be treated safely and effectively. Even better, it can often be prevented.

      How DASH can help

      High blood pressure usually develops over time, starting with a condition known as pre-hypertension, an important health issue we tell you more about in Chapter 6. Note that these numbers are lower than they used to be. The High Blood Pressure Guidelines were modified in 2017. Picture-perfect blood pressure is pegged at around 115/75. Doctors don’t classify blood pressure as hypertensive until the systolic blood pressure (the top number) gets to 130 to 139 or the diastolic blood pressure (the bottom number) hits 80 or above (see Chapter 6). In between, you have elevated blood pressure when your blood pressure is running at about 121 to 129 over 80. As many as 50 percent of Americans, fit this profile. More concerning is that about 20 percent don’t even realize they have hypertension, so it’s important to get your blood pressure checked regularly.

      When you’re living in the pre-hypertensive zone, you carry a higher risk for heart disease and stroke than someone whose pressure is normal. To be more precise, every 20-point rise in systolic blood pressure or 10-point rise in diastolic blood pressure doubles the risk of heart disease and stroke. In this range, medications aren’t recommended. Instead, pre-hypertension is a wake-up call to get working on a healthy way of life. Say hello to DASH.

      

DASH is often thought of as a high blood pressure diet, but it was designed to help people with pre-hypertension as well. In order to get into the study, a blood pressure higher than 120/80 was required. If you’re pre-hypertensive, you can expect to drop your systolic blood pressure by a very respectable 7 points. For many people with pre-hypertension, that’s enough to move back into the normal range.

      How does DASH work its magic on blood pressure? For starters, it’s abundant in fruits and vegetables. Plants provide a wealth of health-boosting vitamins, antioxidants, and phytochemicals (see Chapter 5 for more about these disease-fighting substances), and they’re loaded with blood pressure–friendly potassium. Potassium works in opposition to sodium, lessening its effect on blood pressure. It may also have beneficial effects on the tone and health of your blood vessels. A potassium bonanza, DASH provides twice the amount of potassium found in a typical Western diet. Of course, it’s also low in sodium.

      DASH also promotes consumption of low-fat dairy, and research has found that a diet rich in low-fat dairy products such as yogurt and low-fat milk and cheese has consistently been linked to lower blood pressure. In the National Heart, Lung, and Blood Institute’s Family Heart Study, those with the greatest intake of dairy products were about one-third less likely to have hypertension. Not only do these foods provide a great source of calcium, which helps keep your arteries strong and flexible, but with DASH, they also replace less-healthy saturated fats and processed foods.

Wondering whether you can pop some potassium and calcium supplements and get the same effect as if you were eating foods rich in these nutrients? Forget it! Your body is an expert at extracting nutrients from food, but unless you have a medical deficiency, supplements won’t do the same job. In addition, DASH promotes modest weight loss, which also leads to lower blood pressure. You can’t expect to eat a burger and fries followed by a potassium chaser and get the same effect.

DASH and Cholesterol

      Your doctor, your family, and even your TV set are always nagging you about cholesterol. Why do they care, and what exactly is the stuff, anyway? Cholesterol is a waxy substance that comes from your diet but is also made by your body. Although it’s often lumped in with fats, it’s technically a lipid, a broader category that also includes fats. There’s a lot of confusion between dietary cholesterol and the cholesterol made by your body, so we want to clear things up.

      

Everyone’s body creates some cholesterol. Some people are genetically super-producers; others naturally manufacture pretty meager amounts of the stuff. That’s why cholesterol in the diet doesn’t have a huge influence on the cholesterol level in the blood. It’s the type of fat in the diet that you want to focus on. Metabolic studies have long determined that a high level of saturated fat in the diet leads to higher cholesterol levels in the blood. Always check out the amount of saturated fat on the food label. Fiber also helps reduce blood cholesterol levels, especially the soluble fiber found in plant foods. Total recommended fiber intake (insoluble and soluble) is 25 to 35 grams per day. Eating 5 to 10 grams of soluble fiber (barley, oats, quinoa, beans, legumes, vegetables, fruits) a day has been shown to reduce cholesterol by 5 to 10 points or more. Learn more about fiber in Chapter 12.

      Why cholesterol matters

      The two types of cholesterol circulating around in your blood that you need to concern yourself with are low-density lipoprotein (LDL) and high-density lipoprotein (HDL).

       LDL is the “bad” cholesterol because it’s the one that clogs up arteries. You need a little bit of it to keep your cell membranes healthy, your brain working smoothly, and your hormones at healthy levels, but most people’s bodies make far more than they need. Most of the LDL swimming through your bloodstream is generated in your liver, a highly creative organ that can make cholesterol out of just about any sort of food. Dump in a load of saturated fat (coconut oil, animal fats) and it goes to town. Trans fat (found in partially hydrogenated oils, especially hard margarine and shortening, and many processed baked goods) revs up the liver’s cholesterol-creation system even more. Carrying around some extra body fat, especially the type that collects around your tummy, also boosts LDL production. Smoking does too.

       HDL is the good stuff that works to protect your blood vessels. It works in opposition to LDL, pulling bad cholesterol out of the arteries and taking it back to the liver to be processed and eliminated. In general, the higher the HDL the better. Monounsaturated fats (from olive oil, avocados, and nuts), exercise, and alcohol in moderation raise HDL. Think “H is for happy; L is for lousy” if you have trouble remembering which cholesterol is which.

      If your LDL level is high, then you may be more likely to suffer a heart attack or stroke, whereas high levels of HDL may help protect you. The optimal levels vary, depending on your other risk factors. These include hypertension, diabetes, smoking, and whether you’ve already started to develop cholesterol plaque in your