Selenium and heart disease


Epidemiological evidence supporting the possible role of low selenium levels in the development of cardiovascular disease comes from ecological observations, comparisons in the case-control and prospective research.

Regrettably, research and cross-case control approaches suffer from their inherent bias and have contributed little to our understanding of selenium and its relation to atherosclerosis in the development of heart disease (24).

In this same review, we found differences between the findings of epidemiological research, with three of them suggest the existence of a relationship between low selenium levels and increased the chances of heart disease, while two others conclude that there is no such relationship.

However, it has been concluded that the research conducted in Scandinavia do not rule out the hypothesis of an inverse association between trace mineral concentration in blood serum and the risk of ischemic heart disease in conditions of low intakes of selenium, indicated by average selenium levels in blood and serum, with 60 and less than 45 ug / liter, respectively (25).

Research carried out in two countries with low levels of selenium, England and New Zealand, could not find any correlation between traditional risk factors for cardiovascular disease and blood selenium levels or activity of glutathione peroxidase , which is another indicator of the level of selenium (26).

Some very positive effects of selenium on heart problems stem from a number of studies of interventions. The effect of selenium supplementation has been tested on 81 patients with acute myocardial infarction in a double-blind, placebo-controlled study. Patients were randomly divided into two treatment groups who were administered rich in selenium yeast (100 ug / day) or placebo in addition to conventional pharmacological therapy for a period of 6 months. During treatment, the mean serum selenium concentration increased from 82 ug / 122 ug / I (p <0.001) in the group supplemented with selenium, and was unchanged in the placebo group of 83 ug / l) . During the follow-up period of 6 months, there were 4 deaths of cardiac origin in the placebo group, whereas none of the patients in the selenium group died during the follow-up period. Furthermore, there was no fatal reinfarction 2 in the placebo group and non-fatal reinfarction in the selenium group. These results indicate the effectiveness of antioxidants in the prevention and therapy of acute myocardial infarction (27).

One of the first and most pronounced signs of selenium deficiency syndrome is impairment of mitochondrial respiration. Possible explanations for this phenomenon include the membrane disruption as a result of the accumulation of lipid peroxide, ubiquinone (coenzyme Q10) deficiency and damage respiratory enzymes in iron. It is also known, of course, that high levels of selenium nutritional optimize the function of mitochondria. This was confirmed in a study in which a combination of selenium and vitamin E, with intakes of 100 ug and 400 IU per day, respectively, produced substantial symptomatic improvement in angina during a double-blind trial (28).

In a normal human group, the serum levels of selenium in dependence was found in both age and sex. The reasons for these differences are complex and it is impossible to generalize about them, but it is interesting to note that women showed serum levels significantly higher than men in the age groups of 41-50 and 51-60 years. The average selenium concentration of 1083 nmol / L. in a group of men of 41-50 years of age was similar to that observe in the average value of 900 nmol / L in the experimental animals. In patients with leg general arteriosclerosis were observed at significantly lower levels of selenium in serum than in healthy controls (p <0.05), demonstrating that these patients are selenium deficient. No correlations were found between vitamin E and selenium concentrations and activity of glutathione peroxidase in patients with arteriosclerosis general or localized.

In patients hospitalized with acute myocardial infarction, the serum selenium values ​​were significantly lower than in the control group, although they were higher than in patients with atherosclerosis. It should be mentioned, however, an inverse correlation was observed between serum selenium concentrations and mortality rates of patients with myocardial infarction. These facts lead the authors to conclude that selenium treatment could be beneficial for patients with myocardial infarction (29).

It is of interest that the first sign of the relationship between low selenium intake and heart disease is from research conducted in China on populations living in areas of low selenium soils. There is a specific heart condition called Keshan disease which can be prevented completely and, in some cases, be cured by simple dietary supplementation with selenium. This approach can be expected to be beneficial in other cardiac problems associated with low and protracted selenium intakes (30).

Source: Dr Leonard Mervyn - Lamberts

24. Electrolytes Health Elernent DO .. 4. p.7-10. 1990. Salonen, J. T. and HM-JOIN, J.K. Selenium in cardiovascular disease, Ann.Clin.Res.; 13. p.30-35. 1986.
25. Salonen, J. T. and others. Association Between cardiovascular death and myocardial infarction in a seruniselenium asid mat-ched-pair longitudinal study. Lancet, July 24, 1982, p.175-9.
26. ELMS, N. and others. Selenium and Vitamin In relation the risk factors for coronary heart disease. J. Clin Pathol .. 37. p.200-6, 1984.
27. KORPF, LA, H. and others. Effect of Selenium Supplementation acule alter myocardial infarction. Res.Comrn. in Chemical Pathology and Pharmacology, 65 (2), p.249-253, 1989.
28. FROST, D.V. and Lish, P.M. Ann.New.Pharm .. 18. p.259-84. 1975.
29. KOEHLER, H. and others. Cardiology and Angiology Selenium iii. Biol.Trace.Elent.Res .. 15. p.I57-166. 1988:
30. YANG. G. and others. The role of selenium in Keshan disease. Adv.Nutr.Res., 6, p.203-31. 1984.

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