High Potassium Foods

Epidemiological studies are often quoted to show the advantages of different diets. The only problem is that these studies can never show cause and effect. All they can do is show an association.

An association is a great starting point though. It can give you a hypothesis. For example, the Tarahumara Indians do not die of cardiovascular disease (CVD). They have a great many associated characteristics. Among possible associations is their game of kickball in which they run up to 200 miles over several days. They also eat a lot of corn and beans. Or maybe they have unique genetics. These are all associations from which to form a hypothesis. But none of these characteristics can be considered the cause of their lack of heart disease until many other studies are done.

A Framework Is Needed For Understanding

Often an epidemiological study is presented as if it proved whatever the researchers propose as an explanation (hypothesis). However, a single study needs to be put into a framework of other studies so it can be understood. The other studies should include basic related cell biology and other laboratory studies at the tissue, organ and organism levels. At the organism levels it can include other epidemiological studies, as well as experimental studies on humans.

For studies of the health effects of the potassium to sodium ratio of ingested food, the studies would include how potassium and sodium affect the cell, various tissues and organs, and how different potassium sodium ratios affect people. A great many such studies have been done for the potassium sodium ratio. These studies provide a logical framework into which the many studies fit perfectly.

Cellular, Tissue And Organ Studies Are Needed

At the cellular level, it is well understood how potassium and sodium flow in and out of the cell, and the effect of the ions on the various membranes and surfaces within the cell. There are multiple studies on the effect on calcium and other ions, and effect within various cellular compartments.

At the tissue and organ level, the relationship of the two ions has been extensively studied for its effects on muscle, nerve, and bone. The effect on kidneys and adrenals and the interaction with aldosterone, angiotensin and renin, as well as multiple other hormones, has been well established.

Experimental And Epidemiological Studies Are Needed

There have been multiple short term experimental studies on the effect of potassium and sodium on humans. These have shown how these ions influence hypertension, CVD, stroke, osteoporosis and kidney stones.

More and more long term studies are being reported. This blog discussed some studies showing the effect of changing the ratio in the food of Finland here.

Historical studies of primitive civilizations, as well as studies of present day native populations have shown the type of diet consumed before the modern diet. The potassium and sodium content of these diets is relatively accurately estimated. Estimates of the age and type of disease these populations had are also excellent. These studies confirm the importance of the potassium to sodium ratio.

In future posts we will try to discuss each of these major areas in more detail. Many theoretical diets are based on only one or two of these major areas of study. The importance of the potassium sodium ratio has support in all these areas to give a consistent and clear story of why it influences so many areas of health.

Two recent studies are getting a lot of popular attention online. Both studies showed that vegetarians had lower mortality than nonvegetarians. The studies join a large number of similar studies. Although vegetarians as a group do have a lower mortality than nonvegetarians, it probably is not because they exclude all animal products, which is the usual implication. It is most likely because vegetarians have a higher potassium to sodium ratio in the foods they eat.

These two articles are excellent examples of how individual articles need a framework so they can be understood in context. The first article (1) was out of England. The study included a larger number of vegetarians than most studies. Over 15,000 of the over 44,000 participants were vegetarians. This meant that the authors were able to compare vegetarians and nonvegetarians with similar other characteristics such as exercise, smoking, and alcohol consumption. They showed that the vegetarians were less likely to be hospitalized or die from ischemic heart disease.

The second article (2) was a Seventh Day Adventist study of 73,308 subjects and studied various degrees of vegetarianism. They compared nonvegetarian, semi-vegetarian, pesco-vegetarian, lacto-ovo-vegetarian and vegan. The conclusion was that vegetarian diets are associated with lower mortality. The implication is that avoidance of meat is desirable. However, the lowest mortality was found in the pesco-vegetarians. If animal products are the source of worse mortality, this group should not have the lowest mortality. Vegans should have lower mortality than those with any animal products.

A pair of reports (3) we discussed previously had similar findings. One report showed that vegetarians had a lower mortality than nonvegetarians. The second report showed that pesco-vegetarians and lacto-ovo-vegetarians had a lower mortality than pure vegans. What was interesting in these reports is that both reports were on the same group of people. The researchers simply divided the data differently in the two reports.

Processed Meat Clue

Another recent study (4) gives a clue about what goes on with these large population studies. This particular study included more than 448,000 people. They found a mortality correlation with processed meat. The higher the processed meat consumption, the worse the mortality.

Red meat eaters tended to also eat processed meat and thus did worse. But eliminating the processed meat effect for the red meat eaters eliminated their higher mortality. Poultry consumption did not lead to higher mortality.

Processed meat has a very high ratio of sodium to potassium. Other factors in meat processing may also contribute to the problem, such as nitrosamines, and aromatic hydrocarbons and amines. But neglected in the majority of studies is the ratio of sodium to potassium in the diet. Processed meat consistently has a horribly poor ratio of sodium to potassium. See the sausage and processed meat table here.

Emerging Areas Of Knowledge

There is increasing knowledge concerning phytochemicals, antioxidants, AGEs and other substances in our food. The relationship of genetics to nutrition (nutrigenomics) is slowly emerging. Eventually this knowledge can be put into a framework to show the relative importance of each of these factors. At present their relative importance is unclear.

Potassium To Sodium Ratio Has Clear Effects

However, there is a very clear framework for the relation of sodium to potassium in our food and how it affects our body. Until they can be placed in a framework, the studies of these other components remain isolated bits of information. But the evidence for the role of food’s potassium to sodium ratio in hypertension, cardiovascular disease, osteoporosis and kidney stones is strong. It presents a clear, consistent story.

Next post we will present an overview of the framework for the potassium to sodium ratio that has been assembled by researchers throughout the world. Putting the research done on how potassium and sodium affect the cell, the organs, and hormones together with large epidemiologic and historical studies gives a very clear framework into which many otherwise unclear studies can be placed.

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1. Risk of hospitalization or death from ischemic heart disease among British vegetarians and nonvegetarians: results from the EPIC-Oxford cohort study. Crowe FL, Appleby PN, Travis RC, Key TJ. Am J Clin Nutr. 2013 Mar;97(3):597-603. doi: 10.3945/ajcn.112.044073. Epub 2013 Jan 30.

2. Vegetarian Dietary Patterns and Mortality in Adventist Health Study 2. Michael J. Orlich, MD; Pramil N Singh, DrPH; Joan Sabaté, MD, DrPH; Karen Jaceldo-Siegl, DrPH; Jing Fan, MS; Synnove Knutsen, MD, PhD; W. Lawrence Beeson, DrPH; Gary E. Fraser, MBchB, PhD. JAMA Intern Med. 2013;():1-8. doi:10.1001/jamainternmed.2013.6473. Published online June 3, 2013

3. http://www.highpotassiumfoods.org/high-potassium-foods/fish-dairy-or-just-vegan-diet-you-decide

4. Meat consumption and mortality–results from the European Prospective Investigation into Cancer and Nutrition. Rohrmann S, Overvad K, Bueno-de-Mesquita HB, Jakobsen MU, Egeberg R, Tjønneland A, Nailler L, Boutron-Ruault MC, et al. BMC Med. 2013 Mar 7;11:63. doi: 10.1186/1741-7015-11-63.

Prehypertension is being recognized as the early warning sign of cardiovascular disease. It was recognized officially 10 year ago in The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7)(1), which is a guideline for physicians who treat hypertension. However, many people do not realize they have hypertension or prehypertension.

Prehypertension

Prehypertension is systolic blood pressure between 139 and 120, and diastolic blood pressure between 89 and 80. It is associated with an increased risk of stroke and cardiovascular disease (CVD) (1,2,3). The risk is not as much as when systolic is over 140 or diastolic over 90, but it is twice as much as those who are below the prehypertensive levels.

Giving these blood pressure levels a name and recognizing that there is greater risk with these levels is a step forward. But as pointed out in the last post, for diastolic blood pressure, lower is better to at least 70.

For those between ages 40 and 70 every increase of 20 mm Hg in systolic blood pressure or every increase of 10 mm Hg diastolic will increase the risk of CVD twofold (2). This is true for all blood pressure between 115/75 and 185/115. So if your blood pressure is 135/85, you have twice the risk of getting CVD than if your blood pressure is 115/75. If your blood pressure is 155/95, it is 4 times as much risk. If 175/105, it is 8 times as much.

Why Prevention Is Important

One problem is that if the blood pressure gets to the point it requires treatment, the treatment is not all that effective. By the year 2000, only 34% of patients had achieved adequate control of their blood pressure. This was mostly because patients did not change lifestyle or because the medications failed. Many times medication failure is related to medication side effects.

In both lifestyle change and medication failure, motivation plays a big part. If the medications make you feel weak, feel dizzy, lose mental focus or lose sexual response, you lose motivation to prevent a stroke in the distant future. It is difficult to maintain motivation for the months on end it takes to see blood pressure changes from exercise and weight loss.

If You Are Hypertensive, You Must Stay On Your Medications

There is no question that if you are on medications you must stay on them. Only as your blood pressure improves and your doctor decides to reduce your medications should you change medications. The reduction in stroke and cardiovascular disease in those with lowered blood pressure from medication is dramatic.

But if medications can be reduced, side effects should improve. And if medications can be stopped, it would be best of all. For my wife’s osteoporosis (another disease that can be improved by a high potassium diet), it took several months for her physician to lower my wife’s thiazide diuretic and then take her off it. Expect your physician to be cautious.

How To Prevent Hypertension And Prehypertension

It would be far better to prevent hypertension and prehypertension in the first place. This can be done through lifestyle changes. Lack of lifestyle changes play a big part in hypertensive medication failure. Control of weight, alcohol consumption, physical activity and diet are as important for prevention as they are for treatment.

If your blood pressure is “normal” or prehypertensive, begin to incorporate high potassium foods into your diet. It is the easiest way to begin reducing your blood pressure. A high ratio of potassium to sodium in your diet is the quickest way to see results.

Other lifestyle changes will add even more improvement, but will take longer to show results. Keeping alcohol consumption under 1 to 2 drinks per day, losing weight and increasing physical activity are lifestyle changes that will help most hypertensives.

Reducing weight and increasing physical activity both should be done slowly to allow the body to adapt. If you are overweight, reducing weight will improve systolic blood pressure 5 to 20 mm Hg for every 22 pounds you lose above normal (3). Increasing your physical activity can reduce systolic blood pressure by 4 to 9 mm Hg.

If on the usual American diet, a high potassium foods diet can be expected to reduce blood pressure by 5 to 22 mm Hg.

Tables Of High Potassium Foods

To find tables that have potassium and sodium content of foods in various food groups, click here. It lists many of the posts on this website. Those with tables have “table” in the link. Or you can have a PDF with tables sent to you by signing up below.

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The Seventh Report of the Joint National Committee on
Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC7)

1. full report – http://www.nhlbi.nih.gov/guidelines/hypertension/jnc7full.pdf

2. short report – http://www.nhlbi.nih.gov/guidelines/hypertension/express.pdf

3. physician card – http://www.nhlbi.nih.gov/guidelines/hypertension/phycard.pdf

Last post we discussed that below 120/80 is considered normal blood pressure. However, even though less than 80 diastolic is labeled “normal,” it does not mean there is no benefit from having lower than “normal” diastolic blood pressure.

A graph (1) based on data from the Society of Actuaries and Association of Life Insurance Medical Directors of America 1979 report shows that lower is better. Many medical research studies since then have confirmed these findings.

Lower is better!

No Threshold

A study (2) 23 years ago showed that there is no “threshold” below which the benefits of lower diastolic blood pressure level off. The study examined diastolic blood pressures down to 70 and showed that the lower the diastolic blood pressure the less the risk of stroke and heart attack. So as the graph shows, it is better to have a diastolic of 70 than of 75.

Recent studies, such as (3), continue to show that stroke risk from higher blood pressure is increased in the “prehypertensives.” Those with diastolic between 85 and 89 were at 79% increased risk. Even those with diastolic between 80 and 85 had an increased risk of 22%.

Complications, Complications, Complications

Some of the discussion (4) among doctors treating hypertension is whether to lower the treatment threshold being used today to less than 90 diastolic. Study after study has confirmed the value of getting the blood pressure lower than “normal”. The benefit continues to increase to at least 70 diastolic.

The only reason for having the discussion of how much to lower someone’s blood pressure is because of the side effects of the drugs that treat hypertension. You have to weigh the side effects and complications of treatment against the risk of stroke and cardiac disease that results from the higher blood pressure.

Avoid Complications

If you can lower blood pressure without using drugs, the side effects and complications are no longer part of the discussion. There is no side effect from getting a higher potassium to sodium ratio. Yes, you have to have good kidneys and not have one of the rare and unusual diseases that require a low potassium intake. Otherwise, getting more potassium and less sodium will only improve your health and longevity.

All of the studies mentioned used medication to lower blood pressure. But multiple other studies have shown how to lower blood pressure without medications, using diet and lifestyle changes. Lowering the amount of sodium or increasing the amount of potassium in the diet will lower blood pressure and reduce associated health problems.

Doing both will improve the potassium to sodium ratio even more. The higher the ratio, the better the blood pressure will be.

You can find links to tables of foods that are high in potassium and low in sodium on the list of posts page. Pick some high potassium substitutes in each category of food you include in a meal and you will improve your health.
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1. Society of Actuaries and Association of Life Insurance Medical Directors of America. Blood Pressure Study 1979. Society of Actuaries & Association of Life Insurance Med. Directors of America (1980).

2. Blood pressure, stroke, and coronary heart disease. Part 1, Prolonged differences in blood pressure: prospective observational studies corrected for the regression dilution bias. MacMahon S, Peto R, Cutler J, Collins R, Sorlie P, Neaton J, Abbott R, Godwin J, Dyer A, Stamler J. Lancet 1990 Mar 31;335(8692):765-74.

3. Effects of intensive blood pressure lowering on cardiovascular and renal outcomes: a systematic review and meta-analysis. Lv J, Neal B, Ehteshami P, Ninomiya T, Woodward M, Rodgers A, Wang H, MacMahon S, Turnbull F, Hillis G, Chalmers J, Perkovic V. PLoS Med. 2012;9(8):e1001293. doi: 10.1371/journal.pmed.1001293. Epub 2012 Aug 21

4. Presence of baseline prehypertension and risk of incident stroke: a meta-analysis. Lee M, Saver JL, Chang B, Chang KH, Hao Q, Ovbiagele B. Neurology. 2011 Oct 4;77(14):1330-7. doi: 10.1212/WNL.0b013e3182315234. Epub 2011 Sep 28.

Hypertension is a cellular disease. It is not just high blood pressure. And it is not just because of the pressure pounding against the arteries that people get health problems – a common misconception. But before we discuss the more complex aspect of the cellular disease, let’s discuss the difference between the disease hypertension and the finding of high blood pressure.

Hypertension

Hypertension is a disease, either primary (sometimes called essential) or secondary (caused by another disease). Approximately 95% of hypertension is primary. Only about 5% is caused by a separate disease. It is important that the doctor determines whether or not you are in the 5%. If you are, the underlying disease needs to be treated.

Most patients and doctors think of hypertension and high blood pressure as being the same thing. Because so many people think of them as the same thing we do not usually distinguish between them on most of the posts on this website. In this post we are distinguishing because in the next few posts we will be discussing the disease when the blood pressure is normal or “prehypertensive”.

Primary hypertension is a cellular disease in which the potassium and sodium, inside and outside the cells, are out of balance. Hypertension has effects that go beyond an elevated blood pressure. We will be discussing this in more detail in future posts.

Also, hypertension is not coronary artery disease, cardiovascular disease, arteriosclerosis, or hardening of the arteries. And it is not a nervous tension – being “hyper”.

There is some overlap between these diseases because coronary disease and vascular disease have some aspects in common with hypertension. You can have hypertension without coronary disease and can have coronary disease without hypertension. But there is an association. Hypertension leads to an increased chance for coronary disease, stroke, and other vascular diseases.

High Blood Pressure

High blood pressure (1) is determined by your doctor when the numbers on the test he runs are too high. Almost everyone is familiar with the blood pressure cuff around the arm, and the inflation and slow deflation while the arm is listened to with a stethoscope.

The pressure registered by the cuff when the blood first begins to run into the arm again is the systolic blood pressure. This is the pressure produced when the heart contracts. It gives the number that is “over” the other number.

The diastolic pressure is the pressure when the doctor no longer can hear the blood running in the vessel. This is the pressure in the artery when the heart relaxes between beats. It is the number that is “under” the other.

High blood pressure is a sign (something the doctor notices when he examines you) that something is not right. Most people are unaware that they have high blood pressure in the earliest stage. It does not produce any symptoms that the patient is aware of. As the pressure goes higher and higher it can begin to cause symptoms (something abnormal that the patient notices). By the time it causes symptoms that the patient is aware of, it is far advanced.

Previously, anything below 140 systolic was considered normal and anything below 90 diastolic was considered normal. After insurance companies noticed that people with diastolic pressures in the high 80s had more chance of stroke, heart attack and death, some new criteria began to evolve.

Prehypertension

So although today above 140/90 is still considered hypertension, blood pressure readings between 120 and 140 systolic, and between 80 and 90 diastolic are considered prehypertension instead of normal. Below 120/80 is considered normal.

If above 140/90 is measured on a consistent basis, the doctor will usually prescribe medications. If the pressure is below those numbers, he usually will not. For the 95% of hypertensive patients that have primary hypertension, a high potassium foods diet will usually be helpful in reducing the blood pressure. It may lead to reducing or possibly eliminating the need for medication.

For those in the prehypertensive range, a high potassium foods diet may help stave off the need for blood pressure medication.

You can find links to tables of high potassium foods with the amount of potassium they contain here.

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1. Medline Plus, High Blood Pressure, http://www.nlm.nih.gov/medlineplus/highbloodpressure.html

We have been discussing how Finland was the first to show a dramatic change in a nation’s stroke and cardiovascular disease (CVD) rate by improving blood pressure through diet. An article from 2005 (1) by some of the Finnish researchers was an excellent review of the literature on the role of sodium and potassium to improve blood pressure.

The crux of the article was to make suggestions for governments to change regulations to encourage the food manufacturers to substitute other salts for sodium salt as a preservative. This was what resulted in the biggest change in diet in Finland. In other industrialized nations this would also result in improving blood pressure and reducing the stroke and cardiovascular disease rates.

IOM Report

The Institute of Medicine (IOM) released a report in 2010 (2, 3) that calls for a solution similar to that in Finland. They call for food manufacturers and restaurants to reduce the sodium in their food products. The reduction is to be slow so consumers do not notice the gradual change in taste of the food.

Although it is a step in the right direction this solution will take many years to get results, just as it did in Finland. It also is only half a solution. It ignores the half that can make an even bigger difference – an increase in potassium in the diet.

As shown in the Finland study and multiple others since, the change in the potassium to sodium ratio is all important. Potassium is not addressed in the IOM report, although IOM has addressed it in other reports.

But by changing food manufacturing processes the increasing amount of sodium in the diet may be stopped. An important part of the IOM report is a graph showing just how much sodium intake in the U.S. has increased since 1971. The increase in sodium intake for men has increased from about 2700 mg to over 4000 mg daily in 2006. Similar increases are seen for women and children.

You Can Improve Blood Pressure Quicker Than The American Population

Although it may take decades for the American population to reverse its sodium to potassium ratio, you can do it in days. All you have to do is learn what foods are high potassium foods in each of the major food groups. Learn what cooking methods preserve potassium in the food item. Then plan foods to substitute for the high sodium alternatives in your meals.

Where To Find Food Tables

It is a simple and safe way to improve blood pressure, reverse osteoporosis, and reduce multiple health risks. You can do all this by increasing your potassium to sodium ratio to more than 3 to 1. A high potassium foods diet is the simple key. The high potassium foods can be found in multiple tables on the list of posts page. Click on the posts indicating a table in the desired food group. There are tables on vegetables, fruit, poultry, dairy and all major food groups.

How To Start

There are also posts explaining how to start a high potassium diet, as well as some sample meals. By using high potassium foods and avoiding foods high in sodium, you can quickly change your potassium to sodium ratio. You can get more than 4700 mg of potassium and less than 1500 mg of sodium a day, as shown here.

It has been estimated that for more than 90% of those with hypertension, such a diet will result in a fall in blood pressure. That means fewer blood pressure medications or even none.

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1. Why and how to implement sodium, potassium, calcium, and magnesium changes in food items and diets? Karppanen H, Karppanen P, Mervaala E., J Hum Hypertens. 2005 Dec;19 Suppl 3:S10-9.

2. Summary of: Strategies-to-Reduce-Sodium-Intake-in-the-United-States. 2010

3. Full report of: Strategies-to-Reduce-Sodium-Intake-in-the-United-States. 2010

In the 1960s Finland’s men had the highest amount of CVD in the world and among the highest prevalence of hypertension. In the 1970s the government started a long term public health project to improve the CVD and stroke rate. Within 20 years they had brought down the number of strokes and heart attacks considerably through blood pressure reduction. They had done this by doing a public awareness campaign and by changing the amount of sodium in some of the food supply.

How Finland Reduced Blood Pressure

They used a shotgun approach utilizing both a change in food manufacture and an attempt to change lifestyle. Some of the manufactured foods had lowered amounts of sodium and an increase in potassium. Some of the sodium in table salt and the salt used in food manufacture was replaced with potassium. There also was a public education program to try to change lifestyle. The program encouraged eating more fruits and vegetables. Along with trying to reduce the amount of smoking and alcohol consumption, the program tried to lower blood cholesterol and increase exercise.

Fewer Strokes And Heart Attacks

Twenty years later the stroke and heart attack rate was markedly reduced, and the daily sodium intake had been much reduced. Even more remarkably, the sodium to potassium ratio had improved significantly. These improvements were achieved despite an increase in obesity, an increase in smoking in women and an increase in alcohol consumption in men. The ratio and the amount of sodium and potassium consumed still had a long way to go. And today it continues to have a long way to go. At present, the sodium to potassium ratio in Finland is about the same level as it is in the U.S. As discussed in a 2001 article (1), the change in sodium consumption came from public education and from food manufacturers’ changes. The most educated women had the greatest drop in sodium intake and greatest improvement in the sodium to potassium ratio (2). However, the program in Finland, as in the U.S. at present, focused on reducing sodium without any emphasis on potassium. Manufacturers of table salt replaced some of the sodium with potassium, magnesium and lysine. This helped with the initial drop in sodium consumption. But more changes will be needed to improve in the future.

Finland Still Has A Way To Go

The food group consumption pattern changed quite a bit at first. In the past 10 years it has changed only slightly in Finland. The initial improvement in blood pressure seen in the 20 year study has slowed recently, as has the stroke rate. In the early years the incidence of stroke decreased by 60%. The stroke incidence continues to go down, but now strokes are only decreasing by 13 to 23% (3). The salt consumption went down a lot at first and then slowed. Added salt went from 3.8 gm/da to 2.6 gm/da at first, and then to 2.3 gm/da. Manufacturers of salt added some potassium salt to the normal table salt, so there was less sodium consumed even when salt was added to the food. The main source of sodium now is from meat products. Meat products contribute a higher percentage of sodium than previously. Most meat products in Finland are manufactured products and there has not been a change in the sodium content used in the curing process of meat. Since meat is still a major portion of the food consumed, sodium from meat is the leading source of sodium in the diet.

Changes In Food Group Proportions Are Needed

After the first 20 years, there has been little change in the food groups consumed in Finland. Sausage, egg and meat products are contributing more sodium to the diet. Catered food is also contributing more sodium. The major changes in diet have been a reduction in sodium from bread, fish and fat spreads. So although improvements are slowing in Finland, the Fins gave us the first hint at how to prevent hypertension, cardiovascular disease and strokes. Other population studies, as well as lots of basic science studies have put together a compelling story for the importance of increasing potassium and reducing sodium.

A List Of Food Tables With Potassium And Sodium Amounts

For a list of posts that includes tables with potassium and sodium content of common foods, see here.

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1. J Nutr Health Aging. 2001;5(3):150-4. Nutrition and cardiovascular disease in Finland since the early 1970s: a success story. Pietinen P, Lahti-Koski M, Vartiainen E, Puska P.

2. Eur J Clin Nutr. 2006 Oct;60(10):1160-7. Epub 2006 Apr 26. Sodium in the Finnish diet: II trends in dietary sodium intake and comparison between intake and 24-h excretion of sodium. Reinivuo H, Valsta LM, Laatikainen T, Tuomilehto J, Pietinen P.

3. PERFECT – Stroke PERFormance, Effectiveness, and Costs of Treatment Episodes in Stroke. Atte Meretoja, 2011

One of the earliest studies (1) to clinically show that improving the potassium to sodium ratio can reduce the incidence of high blood pressure, cardiovascular disease and stroke was started in the 1970s. It has been an ongoing study since then.

Finland – Coronary Heart Disease Capital Of The World

In the 1960s Finland’s men had the worst rate in the world of coronary heart disease mortality and among the highest rates of high blood pressure (hypertension). Along with other interventions felt to be helpful at the time, the government sought to reduce sodium intake in the diet. By screening and educating the public, and getting food manufacturers to reduce the sodium in some of their products, they were able to reduce hypertension, cardiovascular disease and stroke in Finland.

The public education also included exercise, weight reduction, smoking cessation, alcohol reduction, and saturated fat and salt reduction. But during the first 20 years the obesity rate increased, alcohol consumption in men increased and smoking in women increased. Despite that, during the 20 year period they were able to bring down blood pressure by 10 mm Hg and reduce the stroke rate by 60%.

Fewer Strokes With Salt Reduction

Salt reduction in the diet is felt to be an important contributor to the lowering of blood pressure and the number of strokes. The sodium consumed did go down and the ratio of sodium to potassium improved.

At the time the study started there was no emphasis on potassium in the diet by the medical community. Because a mixed potassium salt was substituted for some of the sodium salt, there was a greater lowering in the diet of sodium than of potassium. So even though the Fins lowered the amount of potassium they got, sodium was lowered more. This resulted in the ratio of sodium to potassium in the diet improving.

Only 30 More Years To Go

The Finnish diet did not improve much beyond the ratio improvement. And although they have had dramatic improvement in their salt intake and their rate of cardiovascular disease and stroke, researchers estimate it will be over 30 years until the salt intake gets down to the recommended level.

Similar to the U.S. the Finnish government advice to reduce sodium has resulted in people adding less salt to their meals. But manufactured food still contributes a lot of sodium to the diet. Only some foods have less sodium. Food that does not have a reduced amount of sodium is still a major part of the diet. The shift to more vegetables and fruits and less meat has been minimal.

More recent studies from Finland show that there are limits to what can be achieved by reducing sodium in the diet without increasing the proportion of high potassium foods. We will discuss some of the more recent studies next post.

For lists of high potassium foods, click here and look for the food group you are interested in.
1. Karppanen H, Mervaala E. Adherence to and population impact of non-pharmacological and pharmacological antihypertensive therapy. J Hum Hypertens. 1996 Feb;10 Suppl 1:S57-61.

There have been many medical research papers showing a strong improvement in blood pressure, stroke and cardiovascular disease from eating high potassium foods. Recently one (J. Am. Coll. Cardiol. 2011;57;1210-1219) compiled a group of eleven papers that were done in a high quality manner, prospectively with at least 4 years of follow-up. It included 247,000 people.

The study first looked through over 3200 papers mentioning potassium intake and stroke or cardiovascular disease. It eliminated papers until it found those that were prospective and that included enough information to evaluate.

Six of the studies were on Americans, and five came from other countries. None came from the countries that are traditionally those having the highest potassium intake.

The papers looked at strokes and cardiovascular events, and correlated these events with potassium intakes. They found that those with the highest intakes of potassium had a 21% lower risk of stroke or cardiovascular events.

These particular studies did not estimate sodium, so it is impossible to say if changes in sodium intake occurred also. Because of the many studies on sodium showing that a reduction in sodium reduces strokes and cardiovascular disease, it would have been nice to know if it played a role in the present study.

The study was able to correct for some of the other factors influencing strokes and cardiovascular events, such as obesity and hypertension. They were able to show that potassium had an influence separate from these other factors.

Together with many other basic science and epidemiological studies, the evidence for the benefits of potassium in the diet are becoming ever stronger. There are probably multiple mechanisms that potassium uses to improve health, but for those who do not need to restrict potassium, the more foods high in it, the better.

More and more studies are pointing to the advantages of a high potassium diet to reduce blood pressure, stroke and cardiovascular disease. This one was particularly worthwhile because of the quality of the studies it assessed, and the large number of people included in the study.

When you are not getting enough potassium, symptoms are often absent. Although technically not symptoms, hypertension and bone loss are two of the most common effects of not getting enough potassium in the diet. High potassium foods are the best preventive for these two problems, as well as for prevention of kidney stones. Because of the type food that high potassium foods are, it is also the best diet for lowering your chance of heart disease and stroke.

Energy loss and fatigue are common symptoms of potassium lack. But fatigue can occur from so many factors that it is not a reliable way to tell if you are lacking potassium. Statistically, though, odds are that at least some of your fatigue is from inadequate potassium intake. Most Americans consume less than half the recommended amount of potassium. So if energy loss is from inadequate potassium intake, it will improve on a diet of high potassium foods.

Sodium and potassium balance each other out. Sodium and potassium are like the yin and yang of our body’s fluid system. They influence what is kept in our body and in our cells, and what is thrown out. When we get lots of sodium it tells the kidneys to get rid of sodium. Calcium always accompanies the sodium. So the calcium comes out of the bones, leading to osteoporosis with less dense and more fragile bones, and goes into the urine where it can form the most common kind of kidney stones.

Calcium movement also affects our nerve cell and muscle cells. When a nerve cell fires or a muscle cell contracts (including the heart muscle cells and the smooth muscle cells in the blood vessels), it does so because sodium goes from outside the cell to inside the cell and potassium goes the opposite way.

Calcium runs in with the sodium. However getting the calcium out of the cell is not so easy. The calcium has to be exchanged for sodium. There are several pumps and exchangers in our cell membranes to do this. But if there is too much sodium and not enough potassium, not enough calcium gets pushed out.

If not enough calcium gets out of the cell, the muscle cells do not relax fully. When the smooth muscle cells of our blood vessels do not relax, our blood pressure rises and we become hypertensive. When the muscles of our body, such as those in our neck and back, do not relax, we feel tenser and tire more easily.

So the symptoms are subtle and often unnoticed in the early stages. High blood pressure often is unnoticed until there is a stroke or heart attack. Osteoporosis is often unnoticed until a bone is broken. Fatigue and tiredness can be caused by so many things, that we don’t notice how much is due to inadequate potassium.

There are ways to check on whether we are getting enough potassium in our diet. But what you might think is the most obvious – the blood test for potassium – is not the way to check. Potassium is so important that the blood level is kept normal even when our diet is seriously lacking. A normal blood level of potassium is meaningless in terms of diet.

Since high blood pressure is usually without symptoms, you will need to get your blood pressure measured. If blood pressure is high or high normal, lack of potassium in the diet may be the culprit. You can often go to a pharmacy and they will check your blood pressure, or you can get a home blood pressure unit for little money.

If your blood pressure is high or high normal, you may want to try a high potassium diet to see if you can lower it. For those on medication for hypertension, often the dose can be reduced or even eliminated.

For osteoporosis, there is a scan to check bone density. The DEXA scan will check how strong your bones are. This test is usually ordered by your doctor. It can show early bone loss, osteopenia, before there are any symptoms, and before the loss becomes osteoporosis.

Another way for your doctor to check if you are losing too much calcium is by checking the calcium in your urine. This will detect calcium loss even before the bone loss will show up on a DEXA scan.

But the best way to determine if you are getting enough potassium in your diet is to count the potassium and sodium you consume in a day. Keep track of all the food you eat in a day, including the approximate weight of the food items. Then look up the amount of potassium and sodium they contain in the multiple tables here on the website. If you are getting 4700 mg of potassium and less than 1500 mg of sodium, you are eating like the healthiest people on the planet.