The Relationship between Sodium Consumption and Hypertension

High blood pressure, or hypertension (defined as a blood pressure equal to or greater than 140/90 mm Hg), is a prevalent problem in America. Americans tend to consume excessive amounts of dietary sodium, with men consuming more than women [1,2]. Sodium consumption is purported to be an important factor in the incidence of hypertension [3,4]. However, the exact role that sodium plays in hypertension is not clear [3,5]. The independent effect of sodium in hypertension is difficult to denote when many other factors affect hypertension, such as bodyweight, genetics, age, and stress levels [3,5]. Preventing and reducing hypertension is an important public health concern, as hypertension increases the risk of stroke and a variety of cardiovascular dysfunctions [2,3,6].

According to a variety of research, it appears that certain individuals are more susceptible to developing hypertension due to excessive sodium consumption than others. Obesity, older age, and sodium sensitivity are all factors that increase the likelihood of developing hypertension as a result of excessive sodium consumption, and individuals with those characteristics will benefit from limiting dietary sodium [3,5,7]. Those who are younger, at a healthy weight, and not sodium sensitive are less likely to develop hypertension as a result of excessive sodium consumption, and these individuals do not need to be overly concerned with limiting dietary sodium [3,5,7].

Sodium sensitivity and sodium resistance are phenomena that are at least partially regulated by the renin-angiotensin-aldosterone system (RAAS), as the hormones renin and aldosterone play an important role in the blood pressure response due to sodium consumption [7]. However, there is no definite conclusion on what underlies sodium sensitivity [7]. The RAAS response can vary between individuals [7]. Sodium resistant individuals’ RAAS responds with a significant decrease in renin and aldosterone levels when excessive sodium consumption occurs, while sodium sensitive individuals have a markedly lesser reduction in renin and aldosterone in the same scenario [7].

Hypertension increases the risk of stroke and cardiovascular dysfunction, and these risks are even greater in obese people with hypertension [2,3,6]. Obesity also appears to play a role in the RAAS response to excessive sodium consumption [3]. Obesity makes the body more sodium sensitive, placing obese people who consume sodium excessively at a greater risk for hypertension and therefore cardiovascular dysfunction [3].

There is a clear positive correlation between age and hypertension, and older adults tend to be more susceptible to sodium induced hypertension [2,5]. Interestingly, older adults tend to experience greater reductions in high blood pressure as a result of limiting dietary sodium compared to younger people [8].

Dietary sodium limitation is beneficial in preventing and reducing hypertension in those with any or all of the following factors: obesity, older age, and sodium sensitivity [3,5,7]. Dietary sodium limitation is not overly important in those who are normal weight, younger, and sodium resistant [3,5,7].


References

1.) Morris, M. J., Na, E. S., & Johnson, A. K. (2008). Salt craving: the psychobiology of pathogenic sodium intake. Physiology & behavior, 94(5), 709-721.

2.) du Cailar, G., Ribstein, J., & Mimran, A. (2002). Dietary sodium and target organ damage in essential hypertension. American journal of hypertension, 15(3), 222-229.

3.) He, J., Ogden, L. G., Vupputuri, S., Bazzano, L. A., Loria, C., & Whelton, P. K. (1999). Dietary sodium intake and subsequent risk of cardiovascular disease in overweight adults. Journal of the American Medical Association, 282(21), 2027-2034.

4.) Dahl, L. K., & Love, R. A. (1957). Etiological role of sodium chloride intake in essential hypertension in humans. Journal of the American Medical Association, 164(4), 397-400.

5.) Law, M. R., Frost, C. D., & Wald, N. J. (1991). By how much does dietary salt reduction lower blood pressure? I--Analysis of observational data among populations. British Medical Journal, 302(6780), 811.

6.) National High Blood Pressure Education Program. (2004). The seventh report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure.

7.) Shin, S. J., Lim, C., Oh, S. W., & Rhee, M. Y. (2014). The unique response of renin and aldosterone to dietary sodium intervention in sodium sensitivity. Journal of Renin-Angiotensin-Aldosterone System, 1470320314526437.

8.) Law, M. R., Frost, C. D., & Wald, N. J. (1991). By how much does dietary salt reduction lower blood pressure? III--Analysis of data from trials of salt reduction. British Medical Journal, 302(6780), 819.


Disclaimer: The information on this website is not intended to replace or supersede medical recommendations given to you by your physician. Please consult with your physician before making any significant changes to your diet or physical activity levels, especially if you have any preexisting conditions.