High dietary sodium/potassium ratio linked to increased risk of cardiovascular disease

Tuesday, May 08, 2012 by: Helmut Beierbeck
Tags: potassium, sodium, cardiovascular disease

(NaturalNews) For decades now we have been warned against the evils of eating too much salt; an excess of dietary sodium supposedly raises the risk of heart disease. The 2010 Dietary Guidelines for Americans (1) tell us to limit our daily sodium intake to 2,300 mg; even lower values are recommended for older adults and patients with preexisting conditions.

Yet, there has never been any sound basis for these recommendations. For example, a recent meta-analysis (2) of seven studies involving patients with normal and those with elevated blood pressure found no strong evidence of any connection between salt intake and risk of death from cardiovascular disease.

There is, however, a correlation between the dietary sodium/potassium (Na/K) ratio and cardiovascular disease (3). Investigators followed more than 12,000 adult Americans for nearly 15 years, estimated their sodium and potassium intakes from dietary information, and ascertained causes of deaths among study participants. The researchers found that those in the highest Na/K quartile (the 25% with the highest Na/K ratio) were 1.46 times as likely to die from cardiovascular disease and 2.15 times as likely to die from ischemic heart disease as those in the lowest Na/K quartile.

Potassium is the principal cation (positively charged ion) inside cells, and sodium is the main cation outside the cells (4). The proper Na/K gradient across the cell membrane, the so-called membrane potential, is critical for nerve impulse transmission, muscle contraction and heart function. It is not surprising therefore that the dietary sodium/potassium mix should play an important role in our health; the greater the dietary Na/K imbalance, the more difficult it is for the body to optimize its membrane potential.

Just how problematic is today's dietary Na/K mix? The Na/K ratio in the modern diet is about 4 : 1; in primitive diets it's the reverse (4)! Our reliance on processed foods not only increases our sodium intake - they are notoriously over-salted - but it also decreases the consumption of fruits and vegetables, our best sources of potassium.

So, eat your fruits and veggies. It's a simple and safe way to reduce your risk of heart disease, stroke, osteoporosis, and kidney stones, and generally improve your health.

Sources:

2010 Dietary Guidelines for Americans.

http://www.dietaryguidelines.gov/Publications/DietaryGuidelines/2010/PolicyDoc/ExecSumm.pdf" target=_blank>http://www.dietaryguidelines.gov

Taylor RS,Ashton KE, Moxham T et al, Reduced dietary salt for the prevention of cardiovascular disease: a meta-analysis of randomized controlled trials (Cochrane Review), Am J Hypertension 2011;24:843-853.

http://dx.doi.org/10.1038/ajh.2011.115" target=_blank>http://dx.doi.org/10.1038/ajh.2011.115 [Abstract]

Yang Q,Liu T,Kuklina EV et al, Sodium and potassium intake and mortality, prospective data from the third National Health and Nutrition Examination Survey, Arch Intern Med 2011;171(13):1183-1191.

http://archinte.ama-assn.org/cgi/content/abstract/171/13/1183" target=_blank>http://archinte.ama-assn.org/cgi/content/abstract/171/13/1183 [Abstract]

Micronutrient Information Center, Linus Pauling Institute

http://lpi.oregonstate.edu/infocenter/" target=_blank>http://lpi.oregonstate.edu/infocenter/

About the author:
Helmut Beierbeck has a science background and a strong interest in all scientific aspects of health, nutrition, medicine, weight loss, or any other topic related to wellness. You can follow his ruminations on his blog http://healthcomments.info and leave comments on this or any other health-related topic.