- Diseases, Disorders & Conditions
Potassium and Lower Blood Pressure
How much do you know about potassium? You might remember it from chemistry class as the element symbolized by the letter K. You might also recall that it’s a soft, silvery metal that’s never found alone in nature – it’s always part of ionic salts. Your chemistry teacher might have amazed the class by showing how potassium burns in water. Actually, I think that’s one of the few things I remember from chemistry class, as my interests were more in the literature and writing department. Your science instructor might not, however, have impressed upon you and your classmates the importance of this element. Potassium is essential for plants and animals – their cells can’t function without these ions. Luckily, this element is found almost everywhere – in the soil, in plants, in seawater, and in several minerals. We humans need potassium for important body functions, including brain function, muscle control, nerve function, and heart function. It’s also responsible for helping maintain the right balance between electrolytes and body fluids in relation to fluid inside the cells. That’s why potassium plays an important role in blood pressure.
Lower Blood Pressure
There’s a link between potassium and blood pressure. In many cases, potassium can lower blood pressure. How does that work? First, you need to understand what blood pressure is. It’s the amount of pressure placed on the walls of the blood vessels. The more fluid you have in your body, the higher your blood pressure is going to be.
Think of your blood vessels as a water balloon. When you add a cup of water to the balloon, the walls of the balloon are still pliable and aren’t under undue strain. As you add more water to the balloon, however, the wall becomes tighter and tighter as it strains to accommodate the added volume of fluid. That’s sort of the same thing that happens with your vessels with high blood pressure.
The key to lower blood pressure is reducing the volume of fluid. That’s where potassium comes in. It has the ability to pump out sodium from cells, thereby reducing the amount of fluid. The excess fluid is excreted by the kidneys.
Doctors and scientists think that sodium can lower blood pressure by other means, too. For one thing, it seems to cause blood vessels to relax, so that there’s less pressure on the vessel walls. Another popular theory is that potassium has the ability to counteract substances that cause the blood vessels to contract.
Foods High In Potassium
Sources of potassium include several different categories of foods, as well as potassium supplements. If you eat a wide variety of foods, you’re probably getting enough potassium. Potassium rich foods are easy to obtain, and you have lots of choices. Below are some foods high in potassium, so make sure you include these in your diet.
Fruits: tomato juice, fresh tomatoes, bananas, orange juice, oranges, grapefruit, prunes, prune juice, dried apricots, apricots, nectarines, raisins, papaya, pears, cantaloupe, currants, avocados, figs, melons, dates, kiwi
Vegetables and legumes: asparagus, broccoli, artichokes, Jerusalem artichokes, mushrooms, white beans, lima beans, acorn squash, Hubbard squash, butternut squash, zucchini, Brussels sprouts, cabbage, carrots, carrot juice, beets, beet greens, spinach, collards, kale, chard, bamboo shoots, black-eyed peas, chick peas, kidney beans, parsley, lentils, soybeans, pinto beans, parsnips
Dairy: dried milk, skim milk, yogurt
Meats and fish: tuna, mackerel, cod, flounder, pompano, trout, salmon, sardines, clams, chicken, pompano, herring, halibut, turkey, pork, beef, veal
Nuts: almonds, peanuts, pistachios, Brazil nuts
Other: potatoes, sweet potatoes, chocolate, molasses, wheat bran, salsa, ketchup, tomato paste, tomato sauce, spaghetti sauce
The DASH Diet
Are you familiar with the dash diet? DASH stands for Dietary Approaches to Stop Hypertension, and one thing it focuses on is a healthy amount of potassium. It’s a healthy eating plan with lots of benefits. It has the potential to lower blood pressure, to decrease the level of “bad” LDL cholesterol, to help maintain normal blood glucose, and to lower the risk of cardiovascular disease. The diet might also help prevent certain types of cancers and slow the harmful effects of kidney disease. If you need to shed some extra pounds, DASH can help with that, too.
What’s included in the DASH diet? Lots of fruits and veggies – four or five servings of each per day – are recommended, along with seven or eight servings of grains, three of which must be whole grains. Two to three servings of fat free or low fat dairy products are allowed. One or two servings of lean meat, poultry, or fish are allowed. Dried beans and other legumes can be eaten four or five times per week. Fats, fatty foods, and sugar are limited to small amounts.
Notice the amounts of fruits and vegetables suggested as part of the dash diet. That means that dieters will get plenty of potassium, with lower amounts of sodium. They’ll also get lower amounts of fat and higher amounts of fiber, vitamins, calcium, antioxidants, and magnesium. The DASH diet can sometimes lower blood pressure in just two weeks, and it’s recommended by many doctors, the Mayo Clinic, the American Heart Association, and even the U.S. Department of Health and Human Services. That’s pretty impressive.
The DASH Diet:
How Much Potassium Do You Need?
Most doctors agree that healthy adults need 4,700 milligrams of potassium every day, and that includes pregnant women. Women who are breastfeeding, however, need more – 5,100 milligrams daily. Bodybuilders and other athletes might need more, too. Too much potassium can be deadly, but going slightly over the recommended daily amount is usually safe. If, however, you consume several times the amount of recommended potassium, you could experience hyperkalemia. Hyperkalemia is the term used to describe a high concentration of potassium in the blood, which is a serious condition. In fact, if the potassium is concentrated enough, it’s considered a medical emergency and can be fatal. How? By causing cardiac arrhythmia. You might not realize this, but a form of potassium, potassium chloride, is used in lethal injection executions in the U.S. Too much potassium can also be dangerous for people with certain medical conditions, especially kidney disease, and for those on certain medications. It’s always best to talk to your doctor before taking any type of dietary supplements, and that includes potassium tablets.
It’s interesting to note that even though foods high in potassium are everywhere, there are still Americans who don’t get enough of this vital element. In fact, it’s estimated that about 20% of patients admitted to American hospitals have low potassium levels. It’s hard for me to imagine what these folks are eating.
If you’re trying to lower blood pressure, you don’t need to concentrate only on getting enough potassium. You also need to lower your intake of sodium. Most processed foods are high in sodium and low in potassium. Natural whole foods are often just the opposite – low in sodium with plenty of healthy potassium. Another easy way to reduce sodium and add potassium is to use Lite Salt, which is a combination of regular table salt and potassium chloride. It has the same texture as regular salt, and I can’t tell any difference in taste, either.
Most healthy people don’t need potassium supplements, but there are some exceptions. For example, athletes who exercise hard and sweat a lot might need to take potassium tablets. Also, people on some diuretics might need extra potassium. Diuretics help the kidneys excrete more sodium from the body, and sometimes potassium is lost along with the sodium. Not all diuretics, however, cause potassium loss, so don’t turn to potassium supplements just because you take a diuretic. Talk to your health care professional first. Too much potassium can cause a host of problems, including dangerously low blood pressure, weakness, an irregular heartbeat, paralysis, and even death.
So-called “starvation diets” that provide under 800 calories a day can play havoc with your potassium and sodium balance, so you need to watch that. If you have a viral infection, a bacterial infection, or some other condition that causes severe vomiting and/or diarrhea, you might be losing too much potassium. Alcoholics and untreated diabetics can have this problem, too. If you take a lot of laxatives, you’re probably flushing a lot of potassium down the drain, so to speak.
If you’re taking potassium supplements, you need to be aware of the danger signs of hyperkalemia. They include nausea, vomiting, weakness, and fatigue. Symptoms of hyperkalemia might also include breathing difficulties, pins-and-needles sensations, numbness, or tingling. Heartbeat might become slow or irregular, sometimes accompanied by weak pulse. It’s also important to note that sometimes this dangerous condition has no symptoms at all.
Potassium citrate is a salt made from citric acid and potassium carbonate or potassium bicarbonate. Molecularly speaking, it’s made up of potassium, carbon, hydrogen, and oxygen. The salt is alkaline, so it’s often used to neutralize highly acidic substances. For example, people with urinary tract infections might find that urinating is painful, so potassium citrate is sometimes prescribed to make the urine les acidic. This makes urinating less painful.
This salt is often used in the treatment of kidney stones, too, along with gout. For patients who have cardiac arrhythmia caused by a potassium deficiency, potassium citrate is often used as a treatment. Research and experiments involving laboratory rats with kidney disease showed that this salt had a positive effect on kidney function.
Potassium supplements are often in the form of potassium citrate. In some states, it can be purchased over the counter, in tablets or in a powder. There are lots of medications that can interact with this supplement, however, so you need to discuss your medications with your doctor before taking it.
Potassium bicarbonate is a salty compound in the form of crystals or a grainy white powder. You’ve probably consumed potassium bicarbonate lots of times without even knowing it. The compound has several uses. Sometimes it’s added to bottled water to improve the taste, and it’s also used in winemaking and in the production of club soda. It might also be in your fire extinguisher and in the buffered coating on some of the pills you take. If you grow vegetables organically, you might have used this compound to control powdery mildew or to neutralize growing soils that were too acidic.
Sometimes the compound is used in potassium supplements. The tablets are dropped into a glass of water, where they dissolve with an effervescent action. Some of the brand names of these supplements are K-vescent, effervescent potassium, and K-effervescent. Because this substance can cause nausea and upset stomach, it’s best to take it with milk or with food. Potassium bicarbonate can interact with aspirin, ibuprofen, ACE inhibitors, steroids, beta-blockers, and some diuretics.
Potassium iodide is a salt comprised of potassium and iodine. If you use iodized salt, you’re most likely consuming this compound. It’s often found in liquid form, called saturated solution of potassium iodide, or SSKI. The solution is made by dissolving the crystals in water. Because it has a very bitter taste, it’s often added to juice or to a cube of sugar.
Unlike potassium citrate and potassium bicarbonate, potassium iodide is not used as potassium supplements. It’s perhaps best known for its association with nuclear accidents and nuclear bombs. More specifically, it’s used against a form of radioactive iodine that threatens the thyroid. Remember the Chernobyl disaster? After the nuclear power plant accident, SSKI was given to millions of adults and children. Some of the recipients lived in the USSR, but many lived in Poland, which is hundreds of miles from the site of the accident. Did it work? According to follow-up studies, the potassium iodide did work. For those receiving the medication, no thyroid cancer was found. For people living in the threatened area who did not receive the protective measure, thyroid cancer reached epidemic proportions. In that respect, it’s pretty obvious that potassium iodide saved a lot of lives.