What makes selenium and Coenzyme Q10 a good heart health combination supplement? Here, of course, we are talking about supplementation of individuals who have low selenium and CoQ10 blood levels.
Selenium and the Elderly
About selenium status in the elderly, not much is known. Therefore, data from the recently published Newcastle 85+ study are of interest. The researchers assessed the selenium status of 85-year-olds living in the Northeast of England. They measured serum selenium concentrations, selenoprotein P (SELENOP) concentrations, and glutathione peroxidase 3 (GPx3) activity levels [Perri 2024 Mar].
In addition, the researchers studied the relationships between each of those three biomarkers of selenium status. They observed that there was a linear relationship between serum selenium and serum SELENOP concentrations. On the other hand, they found nonlinear relationships between serum selenium levels and GPx3 activity and between serum SELENOP levels and GPx3 activity [Perri 2024 Mar].
Selenium and Good Health
Selenium is an essential trace element for good health. If we are to survive and reproduce, we need some selenium in our diets. Not much but some. The reason is that our bodies cannot synthesize the selenium we need. Many of us live in a region of the world with low selenium content in the soil and in the regionally grown food products. Accordingly, it is difficult for us to get enough selenium in our diet.
For example, Alexander et al point out that mainland Europe and Scandinavia are regions with a low intake of selenium. North America, by contrast, is a region with much higher selenium intake. There is considerable variation in the selenium content of locally cultivated food products around the world. Consequently, daily selenium intake varies considerably. Depending upon the region we live in, we may be at risk of sub-optimal selenium intakes or selenium deficiency [Alexander 2024].
Sex Differences in Selenium Metabolism
Sex differences in selenium metabolism played a considerable role in the heart health outcomes of the KiSel-10 study. In that randomized controlled trial, the researchers administered 200 mcg/day selenium and 200 mg/day Coenzyme Q10 or matching placebos to elderly Swedish study participants with low selenium status. The combined supplementation significantly improved heart function and reduced cardiovascular mortality [Alehagen 2013].
Note that, on average, the baseline selenium status in the KiSel-10 study participants was at a deficiency level, 67.1 mcg/L. The elderly citizens’ CoQ10 level was only borderline satisfactory, 0.82 mg/L at the study start. Prof. Urban Alehagen and the KiSel-10 research team knew that a low selenium intakes and an aging-related decline in CoQ10 bio-synthesis are associated with increased risk of cardiovascular disease [Alehagen 2013; Alehagen 2020].
Selenium and Heart Failure and Immune Function
Selenium has beneficial effects on the prevention and treatment of heart failure. Higher serum selenium levels are associated with a lower risk of new-onset heart failure and with a lower risk of mortality. Now, data from a 2024 cohort study suggest that strengthened immune system function may be a mechanism that explains the positive effect of selenium [Al Mubarak 2024].
In the study, Al Mubarak et al analyzed the data from a cohort of 2,328 patients diagnosed with heart failure. Heart failure is the medical term to describe patients with a heart muscle that cannot pump as much blood out to the tissues and organs as it should. The heart is too weak or too stiff to fill up with blood and pump out blood optimally. Heart failure is frequently associated with a build-up of fluid in the lungs – causing shortness of breath – and in the lower extremities. The bottom line is that heart failure can be life-threatening [Mayo Clinic Staff 2025].
Selenium and Kidney Function
Higher blood levels of the selenoprotein Glutathione Peroxidase-3 (GPx3) are positively associated with good renal function and are inversely associated with cardiovascular and all-cause mortality. Those are the main findings of a sub-analysis of data from the Swedish KiSel-10 study. The KiSel-10 study researchers investigated the effect of combined selenium and coenzyme Q10 supplementation on mortality in elderly community-living individuals low in selenium [Alexander 2024].
GPx3 is a member of a family of eight known glutathione peroxidase antioxidant enzymes. GPx3 catalyzes the conversion of hydrogen peroxide into water. Accordingly, it reduces the extent of oxidative damage to cells. In addition to its oxidoreductase role, GPx3 plays a role in metabolism regulation, in cell growth, in apoptosis, and in signal transduction. In some cancers, it may act as a tumor suppressor [Zhang 2024].
Selenium and Coenzyme Q10 Supplementation for Senior Citizens
In senior citizens, and delayed aging and longevity are associated with the antioxidant and anti-inflammatory protection derived from daily supplementation with selenium and Coenzyme Q10 [Alehagen 2023].
The KiSel-10 Study was a randomized, double-blind, placebo-controlled clinical trial of the effect of combined selenium and CoQ10 supplementation of senior citizens on cardiovascular mortality.
Researchers administered 200 micrograms of selenium in a selenium-rich yeast preparation and 200 milligrams of Coenzyme Q10 in the ubiquinone form or matching placebos to community living senior citizens daily for 48 months [Alehagen 2013].
Summary of Statistically Significant KiSel-10 Study Outcomes
- reduction of cardiovascular mortality in the active treatment group vs. the placebo group (5.9% vs. 12.6%) and better cardiac function observed on echocardiograms in the active supplementation group compared to the placebo group [Alehagen 2013]
- reduction of plasma levels of the N-terminal natriuretic peptide (NT-proBNP), a bio-marker for increased risk of heart failure [Johansson 2013]
- improvement of health-related quality of life and fewer days in hospital [Johansson 2015]
- reduction of cardiovascular mortality in senior citizens with low serum selenium status [Alehagen 2016a; Alehagen 2016b]
- reduction of cardiovascular mortality that persisted after 10 and 12 years in the supplemented group and in subgroups with diabetes, hypertension, ischemic heart disease, and reduced functional capacity due to impaired cardiac function [Alehagen 2015a; Alehagen 2018]
- reduction of plasma levels of two bio-markers for oxidative damage [Alehagen 2015c]
- reduction of plasma levels of six bio-markers for systemic inflammation [Alehagen 2015b; Alehagen 2019b]
- reduction of serum levels of seven bio-markers for fibrosis [Alehagen 2017b]
- reduction of plasma levels of bio-markers for endothelial dysfunction [Alehagen 2020c]
- increase in plasma levels of insulin-like growth factor-1, attenuating an age-related decline in IGF-1 concentrations [Alehagen 2017a]
- reduction of fructosamine concentration compared with the concentration in the placebo group, which tended to increase, important because fructosamine concentration is positively associated with incidence of diabetes and increased blood glucose level [Alehagen 2020b]
- improvement of renal function in elderly citizens deficient in selenium [Alehagen 2020a]
- prevention of an increase in D-dimer levels, which are associated with increased risk of thrombotic disorders [Alehagen 2021]
- association with significant changes in metabolic profiles and with significant changes in the pentose phosphate, the mevalonate, the beta-oxidation, and the xanthine oxidase pathways [Alehagen 2019a]
- association with significant changes in circulating microRNA [Alehagen 2017c]
- structural equation modelling that shows that antioxidant and anti-inflammatory effects are the primary underlying biological mechanisms to explain the success of the KiSel-10 study [Alehagen 2022b]
- decrease in concentrations of fibroblast growth factor 23 (FGF-23) [Alehagen 2022a]
- less shortening of leukocyte telomere length [Opstad 2022]
- increase in serum SIRT1 concentrations [Opstad 2023]
- improvement in serum free thiol levels, supporting a reduction in systemic oxidative stress [Dunning 2023]
- positive effects on five age-related blood biomarkers – ICAM-1, adiponectin, leptin, stem cell factor, and osteoprotegerin – indicating an anti-aging direction compared to placebo [Alehagen 2023].
Conclusion: Delayed aging and longevity associated with Selenium and Coenzyme Q10 for senior citizens
Professor Urban Alehagen and Professor Jan Aaseth have explained an important biological interrelationship between selenium and Coenzyme Q10 and pointed to a theoretical advantage in using both substances in an intervention if there are deficiencies within the population [Alehagen 2015d].
Selenium and Systemic Oxidative Stress
Oxidative stress. A new study shows that selenium supplementation together with Coenzyme Q10 supplementation reduces the levels of systemic oxidative stress in the body. In the study, the reduction of systemic oxidative stress is significantly associated with a reduction in the risk of death from cardiovascular diseases [Dunning & Alehagen 2023].
Oxidative stress: An imbalance of harmful free radicals vis-à-vis protective antioxidants leads to oxidative damage to DNA, lipids, and proteins in the body and to a disruption of redox signaling processes in the cells [Dunning & Alehagen 2023].
In a 2023 KiSel-10 sub-analysis, Prof. Urban Alehagen and his research colleagues investigated the level of free thiols in the serum of elderly study participants taking 200 mcg of selenium and 200 mg of Coenzyme Q10 daily for 48 months [Dunning & Alehagen 2023].
Selenium Supplementation Increases Serum Sirtuin1 Concentrations
Daily supplementation with 200 mcg of selenium and 200 mg of Coenzyme Q10 for four years has resulted in significant increases in serum SIRT1 concentrations. In the parallel placebo group, the serum SIRT1 concentrations decreased significantly [Opstad, Alehagen 2023].
This is the latest evidence from the KiSel-10 Study in which researchers randomly assigned elderly community-living Swedish men and women, average age: 76 years, 49% female, to a combined selenium and Coenzyme Q10 treatment group or to a placebo group [Alehagen 2013].
In earlier papers, the KiSel-10 Study researchers have reported beneficial effects of the combined supplementation of the elderly Swedish citizens with low baseline selenium levels [Alehagen 2022; Opstad 2022]:
Antioxidant Action of Selenium and Selenoproteins
Antioxidants. Several selenoproteins play important roles as antioxidant enzymes in the protection of the cells and the mitochondria against the oxidative damage caused by harmful free radicals. Prominent among the antioxidant seleno-enzymes are the glutathione peroxidases and the thioredoxin reductases [Alehagen 2022].
In many regions of the world, notably in much of Europe and the Middle East, there is selenium-poor soil and selenium-poor foodstuffs. In Sweden, for example, the average daily intake of selenium among senior citizens
is approximately 35 mcg/day, well below the amounts (110–150 mcg/day) needed for an optimal expression of the selenoprotein antioxidants [Alehagen 2022].