View clinical trials related to Vitamin C Deficiency.
Filter by:To evaluate the difference between vitamin C in the form of oral liposomes and general vitamin C in a fixed period of time in plasma and urine.
Nausea and vomiting is a common complication of pregnancy and occurs in 70-80% of all pregnancies. The symptoms usually start 2-4 weeks after fertilization and peak between the 9th and 16th week of gestation. In the 22nd week of pregnancy, the symptoms usually resolve. In up to 10% of all pregnancies nausea and vomiting may persist until delivery, which is called emesis gravidarum. In 0.3-2% of all pregnancies, nausea and vomiting occur with a pathological intensity called hyperemesis gravidarum. The cause of nausea and vomiting during pregnancy is unknown, but it is believed that the stimulus is the placenta and not the fetus. Antihistamines have proven to be an effective therapy. Histamine is increasingly produced during pregnancy by mast cells in the endometrium and myometrium, but also by mast cells in the placenta and in the decidua. High expression of the histamine-producing enzyme histamine-decarboxylase (HDC) in the placenta and many histamine receptors at the feto-maternal transition in the decidua indicate a physiological role of the histamine during pregnancy. The antidote is diamine oxidase (DAO), which is produced in the decidua and trophoblast and breaks down histamine. DAO acts as a barrier to prevent excessive passage of histamine into the maternal and fetal circulation. DAO levels increase exponentially in the first 20 weeks of pregnancy to 1000 times the baseline before pregnancy. It has been shown that intravenous vitamin C significantly reduces blood histamine levels in both allergic and non-allergic disorders. Another study with the German Navy also proved that oral vitamin C administration can reduce nausea in seasickness. In an Australian study in 2016, it was shown that chewing gum was not inferior to ondansetron therapy in patients with postoperative nausea and vomiting (PONV). From the available literature, we conclude that high maternal histamine concentrations in early pregnancy may be a cause of nausea and vomiting, whereas DAO is not sufficiently expressed by the transfer of histamine from the decidua and trophoblast into the maternal circulation prevent. Vitamin C has been identified in controlled clinical trials as a way to lower blood histamine levels. Furthermore, chewing gum was already described as a treatment option for nausea and vomiting. The aim of this study is therefore to test whether chewing gum containing vitamin C in pregnant women with emesis gravidarum has the potential to reduce nausea and vomiting and to evaluate a possible association between maternal human chorionic gonadotropin (hCG) or histamine levels and the severity of nausea and vomiting in early pregnancy as well as the influence of other factors such as thyroxine and pyridoxine.
The goal of this study is to perform a randomized clinical trial to assess the effects of vitamin C versus placebo on wound healing in mandibular fracture patients.
The clinical finding of skin rashes which appear after a vitamin C deficiency in Long Term Care Unit leads us to believe that the institutional diet could predispose to this kind of deficiency. Vitamin C has a key role into the struggle against oxidant stress and is involved into the connective tissue formation of the skin and the vascular endothelium. Vitamin C deficiency affects currently 15 to 25% of the elderly over 65 years old reaching 15% women and 20% men after 65 according to Johnston and Al. It concerns mainly the people in precarious situations (persons without fixed homes, ethyl-smoking persons) and elderly over 65 years. Hypovitaminosis C, defined by plasma level between 5 mg/L and 15 mg/L (28.41 to 85.23 µmol/L), is currently undiagnosed, especially with people with a risk of food deficiency and its prevalence increases with age. The treatment consists of a daily oral supplementation of 1 gram of vitamin C/d for 15 days. A minimum intake of 10 mg/D of vitamin C is required to prevent scurvy and maintain a total pool of 350 mg. A diet modification by a systematic intake of 2 glasses of fresh orange juice and/or the consumption of raw fruits and vegetables would prevent the appearance of scurvy.
The aim of this study is to evaluate the bioavailability of "Novo C Plus" vitamin C containing dietary supplement compared to licensed vitamin C medications. The novelty of this product is the liposomal formulation.
There is suggestive evidence that vitamin C and vitamin D deficiency may increase blood pressure across the range of blood pressures from normal to elevated. Information about this relationship is inadequate in part because of the rarity of individuals with subclinical vitamin C and D deficiency. The investigators have observed subnormal to deficient plasma vitamin C and 25-hydroxyvitamin D levels in a large proportion of patients under active treatment in the investigators' hospital. The clinical implications of widespread hypovitaminosis C and D are unknown. In this randomized prospective comparison trial the investigators will measure vitamin levels and blood pressure in clinically stable acutely hospitalized patients with a wide range of diagnoses, and expected to remain in the hospital for at least 7 more days. The investigators will examine for an inverse relationship between baseline vitamin level and blood pressure across the range of blood pressures. Consenting patients will be randomized to receive vitamin C (500 mg twice daily) or vitamin D (1000 IU twice daily) for as long as 10 days. Blood pressure will be re-measured every 2 days and vitamin levels re-measured on the last study day. Treatment courses of at least 5 days will be considered sufficient for analysis. The hypothesis is that either treatment will reduce blood pressure in patients whose baseline systolic blood pressure is 110 or more; the investigators will also examine whether the reduction in blood pressure with treatment is proportional to the increase in the circulating vitamin level with treatment.