Summary The recommended dietary allowance (RDA) of vitamin C has traditionally been based on the prevention of the vitamin C deficiency disease, scurvy. While higher intakes of vitamin C may exert additional health benefits, the limited Phase III randomized placebo-controlled trials (RCTs) of vitamin C supplementation have not found consistent benefit with respect to chronic…
Summary The increased production of reactive oxygen species plays a role in the etiology of hypertension, but the effects of antioxidants on blood pressure are controversial. However, antioxidants possibly lower blood pressure in elderly patients with hypertension, because vascular aging is also closely related to oxidative stress. Effects of chronic treatment with ascorbic acid (CAS…
Summary Background: Essential hypertension is characterized by endothelial dysfunction, arterial stiffness, and increased oxidative stress. We evaluated the effect of short-term combined treatment with the antioxidants vitamins C and E on endothelial function, arterial stiffness, and oxidative stress in untreated essential hypertensive patients. Methods: A randomized, double-blind, placebo-controlled, crossover study design was used to assign…
Summary Background: In chronic smokers there is evidence for increased formation of oxygen-derived free radicals within the vessel wall impairing endothelial function. It has been suggested that the inactivation of endothelium-derived nitric oxide by oxygen free radicals contributes to endothelial dysfunction. Hence, we tested the hypothesis that in chronic smokers the antioxidant ascorbic acid could…
Summary We report a case of a man in his 60s who developed pulmonary arterial hypertension (PAH) in association with profound vitamin C deficiency. Decreased availability of endothelial nitric oxide and activation of the hypoxia-inducible family of transcription factors, both consequences of vitamin C deficiency, are believed to be mechanisms contributing to the pathogenesis of…
Summary In recent years, many studies have shown positive effects of vitamin D on health, including various benefits to inflammation and immune response, cognitive function, protection against metabolic syndrome and cardiovascular disease. Vitamin D deficiency has been closely related to the development of coronary heart disease and its mortality.Vitamin D involvement in mitigating the pathogenesis…
Summary This study aimed to assess the effect of Vitamin C on blood pressure (BP), and subsequently on oxidative stress and nitric oxide (NO) release, following the low-intensity exercise in the patients. This study included 24 patients with type 2 diabetes mellitus (T2D) (age, 53 ± 7 years; hemoglobin A1c, 10.1% ± 0.9%) randomized into…
Summary Chronic vitamin deficiency is an underlying cause of many modern human chronic diseases, including cardiovascular disease (CVD). A major pathological mechanism leading to the development of CVD is loss of vascular-wall integrity, a structural weakness that triggers the atherosclerotic process. The arterial wall is composed of the constituent cells and surrounding extracellular matrix (ECM).…
Summary Background: In observational studies, increased vitamin C intake, vitamin C supplementation, and higher blood concentrations of vitamin C are associated with lower blood pressure (BP). However, evidence for blood pressure-lowering effects of vitamin C in clinical trials is inconsistent. Objective: The objective was to conduct a systematic review and meta-analysis of clinical trials that…
Summary Vascular calcification is a pathophysiological process that is associated with coronary atherosclerosis, and is a prognostic marker of cardiovascular morbidity and mortality. The process of arterial wall calcification is triggered and accompanied by pro-osteogenic phenotypical modifications of resident smooth muscle cells (SMC). Vitamin C (ascorbic acid) is an essential nutrient required to support the…
Summary Background: Ascorbic acid is an essential vitamin and a powerful antioxidant. Many studies have highlighted the benefits of ascorbic acid for chronic cardiovascular diseases such as hypertension in which angiotensin II (Ang II) plays an significant role. We therefore hypothesized that ascorbic acid could modify the pharmacological properties of the AT(1) receptor for Ang…
Summary Plant-derived bioflavonoids have been recognized to support arterial wall structural integrity and interfere with a variety of pro-atherosclerotic stimuli. This study examined the effect of various bioflavonoids on angiotensin II-stimulated contraction by human aortic smooth muscle cells (SMC) embedded in a three-dimensional collagen matrix. Bioflavonoid inhibition of SMC contraction was found to be dependent…
Summary The lowering blood pressure effect of vitamin C (VC) has been evaluated in various models. As VC has a fast degradation rate in the body after consumption, a study of the frequency-dependent manner of VC is essential for the sustained antihypertension effect of VC. In this study, we investigated the frequency and dose dependency…
Summary Aim: The primary aim of this study was to investigate whether ascorbic acid (AA) supplementation improves postprandial glucose responses under free-living conditions in individuals with type 2 diabetes. A secondary aim was to investigate the effect of AA supplementation on blood pressure. Materials and methods: A total of 31 individuals with type 2 diabetes…
Summary Quinone derivatives like 2-(4-hydroxyphenyl) amino-1,4-naphthoquinone (Q7) are used as antitumor agents usually associated with adverse effects on the cardiovascular system. The objective of this study was to evaluate the cardioprotective effect of ascorbate on Q7-induced cardiovascular response in Wistar rats. In this study, blood pressure, vascular reactivity, and intracellular calcium fluxes were evaluated in…
Summary Vitamin C has recently been identified as an epigenetic regulator by activating ten-eleven translocases (TETs), enzymes involved in generating DNA hydroxymethylcytosine (5hmC). Currently, we investigated whether high-dose vitamin C promotes neuroprotection through epigenetic modulation of 5hmC, if there are sex-specific differences in outcome, and the therapeutic potential of vitamin C in stroke-related comorbidities in…
Summary Background and purpose: Epidemiological evidence suggests that vitamin C may decrease the risk of stroke. The purpose of the present study was to examine the association of serum vitamin C concentration with the subsequent incidence of stroke. Methods: In a Japanese rural community, a cohort of 880 men and 1241 women aged 40 years…
Summary Aims: There is evidence that formation of free radicals increases in patients with hypertension or hypercholesterolaemia, which may contribute to endothelial dysfunction of epicardial coronary arteries due to inactivation of the vasodilator NO. The present study was designed to test whether the abnormal constriction of epicardial coronary arteries due to sympathetic stimulation by the…
Summary Introduction: Plant-derived bioflavonoids have been recognized to support arterial wall structural integrity and interfere with a variety of pro-atherosclerotic stimuli. In this study we tested the effects of bioflavonoids on the contractile activity of cultured human aortic smooth muscle cells (SMC) embedded in a three-dimensional type I collagen matrix. Methods: Collagen I solution mixed…
Summary Impaired arterial smooth muscle contractility plays a leading role in the development of systemic hypertension. Structural changes, such as occlusive atherosclerotic plaque formation, and functional changes, such as hormonal disturbances, play roles in pathophysiological mechanisms of altered arterial contractility. Accelerated gel contraction was accompanied by elevated secretion of MMPs into cell culture media. We…
Summary This study, executed by Chinese research departments, investigated the effects of the amino acid taurine on high blood pressure and vascular function in patients with early-stage high blood pressure. 120 individuals received either a taurine supplement or a placebo for 12 weeks. Taurine supplementation showed, among others, a significant decrease in blood pressure levels…
Summary In this Italian study, 36 individuals with early-stage high blood pressure received a mixture containing several vitamins and magnesium or a placebo for 16 weeks. The results showed significantly reduced blood pressure levels in patients in the supplementation group compared to patients in the placebo group. This study demonstrated that specific nutrients can reduce…
Summary Magnesium deficiency can result in multiple symptoms and is frequently observed in older people. This review investigated the beneficial effects of magnesium to prevent high blood pressure in this age group. The analyzed studies found clear evidence that there is a close relationship between magnesium deficiency and high blood pressure, which supports previous findings…
Summary This study, executed by Iranian researchers, aimed to assess the effect of vitamin D supplementation on high blood pressure. During the investigation, patients with low and very low vitamin D levels and high blood pressure were involved. The patients received either a vitamin D supplement or a placebo. Blood pressure was measured before and…
Summary Without proper treatment, high blood pressure can induce various severe complications. Studies showed that dietary supplements containing, for instance, magnesium and potassium can be used to effectively lower high blood pressure. The studies analyzed in this review may open new vistas in alternative non-pharmaceutical treatments of high blood pressure. For all details, please see…
Summary Obesity is associated with chronic inflammation. Thus, this study investigated the anti-inflammatory capacity of vitamin C in obese patients. 64 obese participants with high blood pressure and/or diabetes and high levels of inflammatory markers were enrolled into either the experimental group (31 patients) or the control group (33 patients). The experimental group was treated…
Summary According to research, low vitamin D levels are associated with higher blood pressure. This study, executed by research departments in Switzerland and the USA, aimed to determine whether higher daily vitamin D supplementation (2000 IU or 50µg) is more effective in controlling blood pressure among older adults than vitamin D supplementation with a standard…
Summary This study by different Chinese research institutes investigated the effect of coenzyme Q10 on several risk factors for cardiovascular diseases in patients with abnormal blood lipid levels. 101 patients who did not take any lipid- or glucose-lowering drugs received coenzyme Q10 (120 mg) or a placebo daily for 24 weeks. Several parameters were measured…
Summary A study executed by researchers from Germany and Northern Ireland showed that a diet rich in flavonoids improves gut health by creating a more diverse composition of the microbiome. The study was performed with 904 German people. Specifically, an association of up to 15% was observed between lower systolic blood pressure and flavonoid-rich food,…
Summary A study conducted in the USA investigated the efficacy of quercetin against high blood pressure (hypertension). For this purpose, participants with elevated blood pressure values and participants with a mild form of hypertension were given 730 mg of quercetin daily for 28 days. It was found that quercetin supplementation contributed to a reduction in…
Summary The Medical University of Poznan in Poland investigated the effect of spirulina algae on the cardiovascular system of obese people with high blood pressure. For this purpose, 50 eligible patients were examined who received a daily dose of 2 g spirulina for 3 months. Positive changes in insulin sensitivity, plasma lipid levels, biomarkers of…
Summary This intervention study investigated the effects of magnesium supplementation on blood pressure and blood flow in the blood vessels. For one month, 48 patients took a daily supplement of 300 mg magnesium oxide. Blood pressure, blood flow, stroke volume, stroke index, cardiac output, cardiac index, left heartbeat, and heart rate were measured. The evaluations…
Summary An analysis of 12 clinical trials investigated the correlation between coenzyme Q10 supplementation, a cofactor of cellular energy metabolism, and hypertension. Based on all results, the researchers concluded that coenzyme Q10 supplementation can reduce systolic blood pressure by up to 17 points (mmHg) and diastolic blood pressure by up to 10 points. Among the…
Summary A study at the University Hospital of Amsterdam with more than 2,700 participants showed that an increased vitamin C intake was associated with lower blood pressure and other positive parameters. Most importantly, the group of people with the highest vitamin C intake had a one-third lower risk of developing coronary heart disease compared with…
Summary A clinical epidemiological study involving more than 2,400 participants in Finland investigated the association between blood levels of vitamin C and the occurrence of stroke. The study participants were patients with hypertension – a condition associated with an increased risk of stroke – who were observed over a period of 10.4 years. The results…
Summary An analysis of 8 clinical trials investigating the association between vitamin C supplementation and essential hypertension showed that vitamin C supplementation led to a significant reduction in blood pressure. For daily supplementation above 500 mg of vitamin C, these results were even statistically significant (P = 0.005). What is particularly remarkable about this research…
Summary In a double-blind, placebo-controlled trial with patients suffering from an early form of hypertension (pre-hypertension and stage 1 hypertension), the effect of quercetin on blood pressure was investigated. This dietary supplement led to a reduction in both systolic and diastolic blood pressure. The reduction in diastolic blood pressure was statistically significant (P < 0.01).…
Summary In an evaluation of 11 double-blind, placebo-controlled trials, the correlation between dietary supplementation with the natural amino acid arginine and changes in blood pressure was investigated. The analysis of these trials showed that arginine supplementation led to a highly significant reduction in both systolic and diastolic blood pressure. One particularly remarkable aspect of this…
Summary This study analyzed the relationship between the intakes of micronutrients (vitamins and minerals) and developing high blood pressure. Vitamin and mineral intakes were estimated from a three-day food record in 120 children. The researchers found that intakes of vitamin D, calcium and potassium were inadequate, whereas sodium intake was considered to be too high.…
Summary We examined the effects on blood pressure, plasma lipoproteins, and platelet function when marine oil supplements (rich in n-3 fatty acids) or vegetable oil supplements (rich in n-6 fatty acids) were added to the usual diets of patients with mild essential hypertension. In a randomized, double-blind, parallel-group study, patients received 50 g of either…
Summary Studies of whether polyunsaturated fatty acids in fish oil–in particular, eicosapentaenoic and docosahexaenoic acids–lower blood pressure have varied in design and results. We conducted a population-based, randomized, 10-week dietary-supplementation trial in which the effects of 6 g per day of 85 percent eicosapentaenoic and docosahexaenoic acids were compared with those of 6 g per…
Summary Both n-3 and n-6 polyunsaturated fats have been suggested to lower blood pressure, an effect ascribed to altered biosynthesis of eicosanoids. To test these hypotheses, we studied blood pressure and eicosanoid production during supplementation of dietary fat for four weeks in 32 men with mild essential hypertension. Supplementation was preceded and followed by four-week…
Summary We investigated the vitamin C (ascorbic acid) status in 1077 eastern Finnish men aged 54 years of age examined in the “Kuopio Ischaemic Heart Disease Risk Factor Study” in 1984-86. Dietary intake of ascorbic acid had a strong linear correlation to plasma ascorbic acid, and we found a clear seasonal variation in the plasma…
Summary This study was undertaken to clarify the mechanism of the antihypertensive effect of coenzyme Q10 (CoQ10). Ten patients with essential arterial hypertension were treated with oral CoQ10 50 mg twice daily for ten weeks. Plasma CoQ10, serum total and high-density lipoprotein (HDL) cholesterol, serum sodium and potassium, plasma clinostatic and orthostatic renin activity, urinary…
Summary Normotensive and hypertensive pregnant women participated in a study to determine the effects of calcium supplementation on blood pressure. Subjects were randomly assigned to control or supplemented groups (1000 mg Ca/d). Blood pressure and serum total and ionic calcium were measured during the 20-wk supplementation period. Calcium supplementation had a significant lowering effect on…
Summary A total of 109 patients with symptomatic essential hypertension presenting to a private cardiology practice were observed after the addition of CoQ10 (average dose, 225 mg/day by mouth) to their existing antihypertensive drug regimen. In 80 per cent of patients, the diagnosis of essential hypertension was established for a year or more prior to…
Summary This study was undertaken to clarify the mechanism of the antihypertensive effect of coenzyme Q10 (CoQ10). Twenty-six patients with essential arterial hypertension were treated with oral CoQ10, 50 mg twice daily for 10 weeks. Plasma CoQ10, serum total and high-density lipoprotein (HDL) cholesterol, and blood pressure were determined in all patients before and at…