POTASSIUM. The Facts. compiled by the Nestlé Research Center

Transcription

1 POTASSIUM The Facts compiled by the Nestlé Research Center

2 A public health concern? Studies have shown that a diet high in sodium or low in potassium is linked with a higher risk for elevated blood pressure and hypertension 1. Elevated blood pressure and hypertension are, in turn, major preventable risk factors for cardiovascular diseases, especially coronary heart disease, stroke and heart failure, as well as renal failure 2.

3 Why do we need potassium? How much potassium is recommended? Potassium is an essential nutrient which may be found within all living cells of the human body. Primarily, potassium functions to regulate water and mineral balance 3. It also plays an important role in electrolyte regulation, nerve signaling, muscle contraction and the tone of blood vessels 4. Daily requirements for potassium can be affected by climate and physical activity, the use of diuretics, and the intake of other electrolytes, notably sodium 4. In adults, depending on age, gender and country, usual recommendations for daily potassium intakes range between 2,000 and 4,700 mg. The World Health Organization (WHO) currently suggests a potassium intake of at least 3,510 mg per day in adults; whereas in children, this amount needs to be adjusted downward based on the energy requirements of children relative to those of adults 5.

4 How much potassium do we consume? What are potassiumrich food sources? Global data suggest that, in many countries, actual potassium consumption is below current recommendations. In countries spread across North America, Europe, Asia and Oceania, the mean potassium intakes range between 1,700 mg (China) and 3,700 mg (Northern Europe) per day 6. Potassium is commonly found in a variety of foods, especially fruits and vegetables, such as leafy green vegetables, tomatoes, cucumbers, zucchinis, eggplants, pumpkins and root vegetables, like potatoes. Potassium is also moderately abundant in beans and peas, tree fruits such as apples, oranges and bananas, as well as milk, yoghurts and meats.

5 Does potassium impact blood pressure? Does potassium impact cardiovascular disease risk? Consistent evidence from a large number of supplementation studies and meta-analyses of these studies indicates that increased potassium intake leads to a decreased blood pressure in both children and adults 7-8. Potassium can also mitigate the negative effects of elevated sodium consumption on blood pressure at least partially through increased renal excretion of sodium First of all, there is a well-established relationship between elevated blood pressure and increasing risk of cardiovascular diseases 12. Moreover, several large cohort studies have found an inverse association between potassium intake and risk of stroke 13. Specifically, in hypertensive people not taking medication for their condition, recent evidence has shown that the reduction in blood pressure following potassium supplementation is not only influenced by the potassium dose, but also by the hypertensive status of the subjects, as well as the sodiumto-potassium ratio of their diet 11.

6 Benefits beyond blood pressure? Can too much potassium be detrimental? Potassium may protect against stroke and other cardiovascular diseases by mechanisms, which are in fact not only related to blood pressure 14. Increasing potassium intake may have other beneficial effects, such as lower urinary calcium excretion, hence reducing the risk of kidney stones and contributing to prevent bone demineralisation 15. Emerging evidence also suggests that potassium could be directly beneficial to the overall vasculature, hence contributing to support the healthy function of highly irrigated organs, such as the heart, the brain, and the kidneys 16. In individuals without impaired kidney function, the body is able to efficiently adapt when consumption of potassium exceeds needs and to excrete excess amounts, mainly through urine 4. Although in some situations, individuals may be more vulnerable to potential adverse effects of potassium (e.g. strenuous activities leading to dehydration, diabetes mellitus, impaired kidney function, drug treatment or other conditions affecting potassium balance), moderate increase in dietary potassium intake to reach recommended levels (e.g. WHO) is considered safe in general for a healthy population 17.

7 Potassium in the context of the overall diet? Overall consideration of the evidence? Increased intake of potassium-rich foods (especially fruits, vegetables, and dairy products including lowfat yogurts and milk) is necessary to reach the current recommendations. Those foods also include many other nutrients that may be beneficial for cardiovascular health, as best illustrated by studies that have assessed the effects of overall dietary pattern such as the DASH (Dietary Approaches to Stop Hypertension) diet 18. Increasing potassium intake is likely to be broadly beneficial to populations around the world 5 given the high prevalance of hypertension in adults globally (about 40% in adults aged 25 and over), the relatively low potassium intake in most populations (well below recommendations) and the clear benefit of increased potassium intake in individuals with high blood pressure. Moreover, WHO considers that a public health intervention aimed at increasing potassium intake from food could be a cost-effective strategy to reduce the disease burden of noncommunicable diseases including cardiovascular diseases 5.

8 REFERENCES 1 Cook NR, Obarzanek E, Cutler JA, Buring JE, Rexrode KM, Kumanyika SK, Appel LJ, Whelton PK; Trials of Hypertension Prevention Collaborative Research Group (2009). Joint effects of sodium and potassium intake on subsequent cardiovascular disease: the Trials of Hypertension Prevention follow-up study. Arch Intern Med. 169(1): WHO (2011). Global atlas on cardiovascular disease prevention and control: policies, strategies, and interventions. World Health Organization, Geneva 3 Young DB (2001). Role of potassium in preventive cardiovascular medicine. Boston, Kluwer Academic Publishers. 4 IOM (2004). Dietary Reference Intakes for Water, Potassium, Sodium, Chloride, and Sulfate. Institute of Medicine. Food and Nutrition Board. National Academies Press, Washington, DC 5 WHO (2012). Guideline: Potassium intake for adults and children. World Health Organization, Geneva 6 van Mierlo LA, Greyling A, Zock PL, Kok FJ, Geleijnse JM (2010). Suboptimal potassium intake and potential impact on population blood pressure. Arch Intern Med. 170(16): Houston MC (2011). The importance of potassium in managing hypertension. Curr Hypertens Rep. 13(4): Aburto NJ, Hanson S, Gutierrez H, Hooper L, Elliott P, Cappuccio FP (2013). Effect of increased potassium intake on cardiovascular risk factors and disease: systematic review and meta-analyses. BMJ. 346:f Whelton PK, He J, Cutler JA, Brancati FL, Appel LJ, Follmann D, Klag MJ (1997). Effects of oral potassium on blood pressure. Meta-analysis of randomized controlled clinical trials. JAMA. 277(20): Binia A, Jaeger J, Hu Y, Singh A, Zimmermann D (2015). Daily potassium intake and sodium-to-potassium ratio in the reduction of blood pressure: a meta-analysis of randomized controlled trials. J Hypertens Jun 2 12 Lewington S, Clarke R, Qizilbash N, Peto R, Collins R, for the Prospective Studies Collaboration (2002). Age-specific relevance of usual blood pressure to vascular mortality: a meta-analysis of individual data for one million adults in 61 prospective studies. Lancet 360: Hunt BD, Cappuccio FP (2014). Potassium intake and stroke risk: a review of the evidence and practical considerations for achieving a minimum target. Stroke. 45(5): He FJ, MacGregor GA (2008). Beneficial effects of potassium on human health. Physiol Plant. Aug;133(4): Lambert H, Frassetto L, Moore JB, Torgerson D, Gannon R, Burckhardt P, Lanham-New S (2015). The effect of supplementation with alkaline potassium salts on bone metabolism: a meta-analysis. Osteoporos Int. 26(4): Oberleithner H, Callies C, Kusche-Vihrog K, et al (2009). Potassium softens vascular endothelium and increases nitric oxide release. Proc Natl Acad Sci U S A. 106(8): EFSA (2005). Opinion of the Scientific Panel on Dietetic products, nutrition and allergies [NDA] related to the tolerable upper intake level of sodium (Request EFSA-Q ). The European Food Safety Authority Journal, 2005, 193: Appel LJ, Moore TJ, Obarzanek E, Vollmer WM, Svetkey LP, Sacks FM, Bray GA, Vogt TM, Cutler JA, Windhauser MM, Lin PH, Karanja N (1997). A clinical trial of the effects of dietary patterns on blood pressure. DASH Collaborative Research Group. N Engl J Med. 336(16): Rodrigues SL, Baldo MP, Machado RC, Forechi L, Molina Mdel C, Mill JG (2014). High potassium intake blunts the effect of elevated sodium intake on blood pressure levels. J Am Soc Hypertens. 8(4):