Faryal Tahir  ( 4th Year Students, Dow University of Health Sciences, Karachi, Pakistan )
Zainab Majid  ( 4th Year Students, Dow University of Health Sciences, Karachi, Pakistan )
Laila Tul Qadar  ( 4th Year Students, Dow University of Health Sciences, Karachi, Pakistan )

Cardiology/American Heart Association (ACC/AHA) 2017 guidelines, blood pressure (BP) in adults can be categorized as normal (<120/<80 mm Hg), elevated (120- 129/<80 mm Hg), or hypertension (HTN) stage 1 (130-139 or 80-89 mm Hg) or HTN stage 2 (> 140 or ? 90 mm Hg). ¹ Because prevention is better than cure, one should emphasize more on the risk factors associated with increased BP rather than various treatment strategies. It is found that populations with low intake of dietary zinc (Zn) have an increased prevalence of HTN, indicating a potential for inverse relation between serum Znlevels and BP. ²  Znis required by human body in very small amounts. Too much or too little of it can affect the body's ability of maintaining BP in its normal range. Zn deficiency has been recently reported as an independent risk factor for the development of HTN by a study published in American Journal of Physiology-Renal Physiology. ³ This study has revealed the role of Zn bioavailability in regulating BP. Findings of the study have concluded that Zn contributes to the adjustment of BP by modulating sodium transport through kidney. ³ It has been demonstrated that there is increased reabsorption of renal sodium because low levels of Zn directly promote sodium-chloride cotransporter (NCC)-mediated sodium reabsorption in the distal convoluted tubules (DCT) of kidney and subsequently causes elevation in BP. ³ So, Zn deficiency directly upregulates renal NCC. ³ Interestingly, reversal of these effects has been noticed with the repletion of dietary Zn. ³ This is how a direct link between dys regulated renal sodium transport and Zn deficiency induced HTN has been established for the first time. ³ Zn deficiency, being a modifiable risk factor for HTN, can be easily overcome. People with gastrointestinal (GI) diseases, vegetarians, pregnant and lactating women, older infants who are exclusively breastfed, sickle cell disease and alcoholics are high risk entities for Zn deficiency. Comparatively, oysters contain more Zn than any other food but red meat and poultry are the most widely consumed sources. ⁴Interpretation of certain mechanisms by which Zn deficiency leads to increased BP may have a vital impact on the management strategies of HTN in chronic disease settings. For instance, physicians should evaluate Zn deficiency promptly and consider it as a separate entity to be managed appropriately. Adequate level of Zn plays a vital role in maintaining BP and ultimately reducing the incidence of devastating sequelae.

Disclaimer: None to declare.

Conflict of Interest: None to declare.

Funding Sources: None to declare.

References

1. Whelton PK, Carey RM, Aronow WS, Casey DE, Collins KJ,

Himmelfarb CD, etal. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults: a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2018; 138:e426- 83.

2. Kunutsor SK, Laukkanen JA. Serum zinc concentrations and incident hypertension: new findings from a population-based cohort study. J Hypertens. 2016; 34:1055-61.

3. Williams CR, Mistry M, Cheriyan AM, Williams JM, Naraine MK, Ellis CL, et al. Zinc Deficiency Induces Hypertension by Promoting Renal Sodium Reabsorption. Am J Physiol Renal Physiol. 2019; 316:F646-53.
4. US Department of Agriculture, Agricultural Research Service. 2011. USDA National Nutrient Database for Standard Reference, Release 24. Nutrient Data Laboratory. [Online] [Cited 2019 February 27]. Available from: URL: doi:10.5455/JPMA.34640