Hippocrates said, “Let food be thy medicine and medicine be thy food.” Most people have gotten the message that high sodium foods raise blood pressure. But the story is more complex. Many studies have identified that minerals such as potassium, magnesium and calcium work to lower blood pressure. Taking the advice of our ancient Greek doctor, what role do foods play in the blood pressure story?
A unique feature of the DASH study was that dietary patterns rather than single nutrients were being tested. The diet was designed to include foods that provide liberal amounts of key nutrients such as potassium, magnesium and calcium. By limiting foods high in saturated fats and cholesterol, the diet pattern shifts to one of plant foods over animal foods thereby also lowering sodium intake. The DASH diet reduced blood pressure by 6 over 3 points (top number 6, bottom number 3) in pre-hypertensive people and by 11 over 6 points in those with hypertension. These improvements occurred with no change in weight.
Pre-hypertension is defined as a consistent blood pressure between 120/80 and 139/89. A consistent blood pressure of 140/90 or higher is reason to take medication in order to reduce risk of heart attack, stroke and heart failure. If you take blood pressure medicine, do not stop taking it without your doctor’s advice. Some blood pressure medications cause changes in our need for potassium. Ask your doctor or pharmacist if you should take potassium supplements or limit high potassium foods.
So, improving blood pressure is not just about eating less salt and high sodium foods. By choosing foods rich in potassium, magnesium and calcium, we are altering what happens at the cellular level to improve blood pressure.
Increasing our intake of fruits, vegetables, whole grains and low-fat dairy foods will improve mineral intake. Many fruits and vegetables like oranges, tomatoes, potatoes, avocados, dark greens, sweet potatoes are rich in potassium. Whole grains like brown rice, cereals with 5g/serving fiber and 100% whole grain breads are rich in magnesium. Choosing reduced fat dairy foods for calcium means limiting cheese, choosing a reduced fat milk and including yogurt and kefir more frequently.
Limiting salty foods like cheese, bacon, ham, sausage, sandwich meats, many canned foods and salty snacks will lower blood pressure. Remember that meats and dairy foods are higher in sodium than vegetables and fruits. To limit sodium, begin by reducing how often you consume these foods.
Gradual changes are easier to make and are more likely to become a habit. Consider designating meatless days. Make a decision to eat more fruit. Have a bowl of whole grain cereal every day for breakfast. Eating out less frequently significantly lowers sodium intake. Tomatoes and avocados are two foods that go well together and are rich in potassium and many other nutrients. This month’s recipe is a simple and delicious salad that goes with any meal. By making a few small changes we can significantly improve basic health such as blood pressure. Let’s grow old gracefully and enjoy our favorite salads with those we love.
Tim Scallon is a registered dietitian nutritionist with many years’ experience practicing nutrition therapy in local hospitals and clinics, teaching nutrition and developing healthy recipes. He helped create the popular TV show Memorial Cooking Innovations celebrating the world of food and health. Memorial Cooking Innovations is produced by St. Luke’s Health and the City of Lufkin. It currently runs in 62 cities and is locally available on Sudden Link cable TV channels and online at www.chistlukeshealthmemorial.org.