A Combination of High-Dose Vitamin C plus Zinc for the Common Cold

Although the role of vitamin C in common cold incidence had been studied extensively, the level of vitamin C intake has not been unequivocally shown to affect the incidence of colds. In the present study the six largest vitamin C supplementation (≥ 1 g/d) studies, including over 5000 episodes in all, have been analysed, and it is shown that common cold incidence is not reduced in the vitamin C-supplemented groups compared with the placebo groups (pooled rate ratio (RR) 0·99; 95% CI 0·93, 1·04). Consequently these six major studies give no evidence that high-dose vitamin C supplementation decreases common cold incidence in ordinary people. Nevertheless, the analysis was continued with the hypothesis that vitamin C intake may affect common cold susceptibility in specific groups of people. It was assumed that the potential effect of supplementation might be most conspicuous in subjects with low dietary vitamin C intake. The average vitamin C intake has been rather low in the UK and plasma vitamin C concentrations are in general lower in males than in females. In four studies with British females vitamin C supplementation had no marked effect on common cold incidence (pooled RR 0·95; 95% CI 0·86, 1·04). However, in four studies with British male schoolchildren and students a statistically highly significant reduction in common cold incidence was found in groups supplemented with vitamin C (pooled RR 0·70; 95% CI 0·60, 0·81). Thus, these studies with British males indicate that vitamin C intake has physiological effects on susceptibility to common cold infections, although the effect seems quantitatively meaningful only in limited groups of people and is not very large.

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Controversy Continues Over Use of High-Dose Vitamin C as Cancer Tx

Internal Medicine News ◽

10.1016/s1097-8690(05)70290-0 ◽

2005 ◽

Vol 38 (7) ◽

pp. 40

Author(s):

NANCY WALSH

Keyword(s):

Vitamin C ◽

High Dose ◽

High Dose Vitamin

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Faculty Opinions recommendation of Vitamin C for preventing and treating the common cold.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717985714.793473942 ◽

2013 ◽

Author(s):

Jonathon Truwit

Keyword(s):

Vitamin C ◽

Common Cold ◽

The Common

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Editorial: Vitamin C and the common cold.

BMJ ◽

10.1136/bmj.1.6010.606 ◽

1976 ◽

Vol 1 (6010) ◽

pp. 606-607 ◽

Cited By ~ 4

Keyword(s):

Vitamin C ◽

Common Cold ◽

The Common

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Protective effects and mechanisms of high-dose vitamin C on sepsis-associated cognitive impairment in rats

Scientific Reports ◽

10.1038/s41598-021-93861-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ning Zhang ◽

Wei Zhao ◽

Zhen-Jie Hu ◽

Sheng-Mei Ge ◽

Yan Huo ◽

...

Keyword(s):

Vitamin C ◽

Escape Latency ◽

Morris Water Maze Test ◽

Protective Mechanism ◽

High Dose ◽

Maze Test ◽

Tnf Α ◽

Histopathologic Changes ◽

High Dose Vitamin ◽

Necrosis Factor

AbstractSepsis survivors present long-term cognitive deficits. The present study was to investigate the effect of early administration of high-dose vitamin C on cognitive function in septic rats and explore its possible cerebral protective mechanism. Rat sepsis models were established by cecal ligation and puncture (CLP). Ten days after surgery, the Morris water maze test was performed to evaluate the behavior and cognitive function. Histopathologic changes in the hippocampus were evaluated by nissl staining. The inflammatory cytokines, activities of antioxidant enzymes (superoxide dismutase or SOD) and oxidative products (malondialdehyde or MDA) in the serum and hippocampus were tested 24 h after surgery. The activity of matrix metalloproteinase-9 (MMP-9) and expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1(HO-1) in the hippocampus were measured 24 h after surgery. Compared with the sham group in the Morris water maze test, the escape latency of sepsis rats was significantly (P = 0.001) prolonged in the navigation test, whereas the frequency to cross the platform and the time spent in the target quadrant were significantly (P = 0.003) reduced. High-dose vitamin C significantly decreased the escape latency (P = 0.01), but increased the time spent in the target quadrant (P = 0.04) and the frequency to cross the platform (P = 0.19). In the CLP+ saline group, the pyramidal neurons were reduced and distributed sparsely and disorderly, the levels of inflammatory cytokines of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 in the serum and hippocampus were significantly increased (P = 0.000), the blood brain barrier (BBB) permeability in the hippocampus was significantly (P = 0.000) increased, the activities of SOD in the serum and hippocampus were significantly (P = 0.000 and P = 0.03, respectively) diminished while the levels of MDA in the serum and hippocampus were significantly (P = 0.007) increased. High-dose vitamin C mitigated hippocampus histopathologic changes, reduced systemic inflammation and neuroinflammation, attenuated BBB disruption, inhibited oxidative stress in brain tissue, and up-regulated the expression of nuclear and total Nrf2 and HO-1. High-dose vitamin C significantly (P < 0.05) decreased the levels of tumor necrosis factor- (TNF)-α, interleukin-6 (IL-6), MDA in the serum and hippocampus, and the activity of MMP-9 in the hippocampus, but significantly (P < 0.05) increased the levels of SOD, the anti-inflammatory cytokine (IL-10) in the serum and hippocampus, and nuclear and total Nrf2, and HO-1 in the hippocampus. In conclusion, high-dose vitamin C can improve cognition impairment in septic rats, and the possible protective mechanism may be related to inhibition of inflammatory factors, alleviation of oxidative stress, and activation of the Nrf2/HO-1 pathway.

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Peroxiredoxin 2 oxidation reveals hydrogen peroxide generation within erythrocytes during high-dose vitamin C administration

Redox Biology ◽

10.1016/j.redox.2021.101980 ◽

2021 ◽

Vol 43 ◽

pp. 101980

Author(s):

Andree G. Pearson ◽

Juliet M. Pullar ◽

John Cook ◽

Emma S. Spencer ◽

Margreet CM. Vissers ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Vitamin C ◽

High Dose ◽

Peroxiredoxin 2 ◽

Hydrogen Peroxide Generation ◽

High Dose Vitamin

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Vitamin C and the common cold

British Journal Of Nutrition ◽

10.1079/bjn19920004 ◽

1992 ◽

Vol 67 (1) ◽

pp. 3-16 ◽

Cited By ~ 74

Author(s):

Harri Hemilä

Keyword(s):

Vitamin C ◽

Clinical Significance ◽

Common Cold ◽

Antioxidant Property ◽

Considerable Decrease ◽

Infected People ◽

Supplemental Vitamin ◽

The Subject ◽

The Common

The effect of vitamin C on the common cold has been the subject of several studies. These studies do not support a considerable decrease in the incidence of the common cold with supplemental vitamin C. However, vitamin C has consistently decreased the duration of cold episodes and the severity of symptoms. The benefits that have been observed in different studies show a large variation and, therefore, the clinical significance may not be clearly inferred from them. The biochemical explanation for the benefits may be based on the antioxidant property of vitamin C. In an infection, phagocytic leucocytes become activated and they produce oxidizing compounds which are released from the cell. By reacting with these oxidants, vitamin C may decrease the inflammatory effects caused by them. Scurvy, which is caused by a deficiency in vitamin C, is mostly attributed to the decreased synthesis of collagen. However, vitamin C also participates in several other reactions, such as the destruction of oxidizing substances. The common cold studies indicate that the amounts of vitamin C which safely protect from scurvy may still be too low to provide an efficient rate for other reactions, possibly antioxidant in nature, in infected people.

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