Supplement

– Cost Effective Supplements

Vitamin C

Quick navigation


What are Vitamin C's other names?

  • 2-oxo-L-threo-hexono-1
  • 3-enediol
  • 4-lactone-2
  • Ascorbate
  • Ascorbic Acid
  • L-ascorbic acid

What is Vitamin C's recommended dosage?

  • Recommended daily intake: 100 - 200 mg

What supplements interact with Vitamin C?

  • Vitamin C and Iron

  • Vitamin C and Zinc

  • Vitamin C and Aloe vera

  • Vitamin C and Green Tea Extract

  • Vitamin C and Melatonin

  • Vitamin C and Vitamin E

  • Vitamin C and Vitamin K


What can Vitamin C help with?

  • Vitamin C for Fatigue

  • Vitamin C for Muscle Soreness

  • Vitamin C for Oxidative Damage

test
Slightly Positive


Data analysis was carried out using Mann-Whitney U test with p < 0.05 being significant by SPSS software version 16.The result of the study showed a significantly decrease in fasting (p = 0.006) and postprandial MDA (p < 0.001) in vitamin C group compare to placebo group but not in lipid profile. This study suggests that vitamin C supplementation can decrease fasting and postprandial oxidative stress and may prevent diabetes complication.


test
Slightly Positive


In conclusion, acute supplementation with a high dose of VC has little or no effect on the hormonal, interleukin-6, or immune response to prolonged exercise and combined ingestion of VC with CHO provides no additional effects compared with CHO alone.


test
Slightly Positive


In contrast, vitamin C supplementation decreased urinary concentrations of DHN-MA (three-way interaction p=0.0304) in nonsmoking men compared with nonsmoking women (p<0.05), as well as in nonsmoking men compared with smoking men (p<0.05). Vitamin C supplementation also decreased (p=0.0092) urinary total of metabolites by ~20%. Thus, HPNE metabolites can be reduced favorably in response to improved plasma ascorbic acid concentrations, an effect due to ascorbic acid antioxidant function.


test
Slightly Positive


Oral supplementation of vitamin C is not associated with changes in markers of oxidation or endothelial activation in healthy male smokers.


test
Slightly Positive


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


test
Slightly Positive


These findings suggest that administration of 1,000 mg of ascorbic acid plus 400 IU of alpha-tocopherol for 6 months is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.


test
Slightly Positive


Uric acid and TAC were decreased in group I on all measurement days. However, we did not observe any differences in the clinical status of patients receiving vitamin C during the first ten days of stroke or after 3 months. Although administration of vitamin C (500 mg/day, iv) to ischemic stroke patients since the first day ischemic stroke resulted in elevated serum levels of antioxidants, it did not substantially improve the clinical and functional status of patients after 3 months.


  • Vitamin C for Vaginitis


What is Vitamin C used for?

  • Vitamin C for Overall health

test
Highly Positive


AA appears to increase FSI, and the differential benefit to noncohabitants suggests that a central activation or disinhibition, rather than peripheral mechanism may be responsible.


test
Highly Positive


Fifty diabetic patients took part in a four-month, double-blind crossover study comparing 500 mg of vitamin C daily with placebo. No significant difference was observed between vitamin C and placebo therapy in fasting whole blood glucose, serum cholesterol, triglycerides, and glycosylated haemoglobin levels.


test
Highly Positive


In conclusion, oral supplementation of vitamin C with metformin reverses ascorbic acid levels, reduces FBS, PMBG, and improves HbA1c. Hence, both the drugs in combination may be used in the treatment of type 2 DM to maintain good glycemic control.


test
Highly Positive


No significant changes in fasting glucose (156 +/- 11 mg/dl), insulin (14 +/- 2 microU/ml), SI(Clamp) [2.71 +/- 0.46 x 10(-4) dl x kg(-1) x min(-1)/(microU/ml)], or forearm blood flow in response to ACh, SNP, or insulin were observed after vitamin C treatment. We conclude that high-dose oral vitamin C therapy, resulting in incomplete replenishment of vitamin C levels, is ineffective at improving endothelial dysfunction and insulin resistance in Type 2 diabetes.


test
Highly Positive


No significant correlations were found between post-race plasma vitamin C, oxidative, and saliva measures, except for a positive correlation between post-race serum cortisol and serum vitamin C (r=0.50, P=0.006). These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and sIgA changes during or following a competitive ultramarathon race.


test
Highly Positive


Therefore, ascorbic acid may have potential therapeutic use in clinical situations where acute hyperglycaemia may be a complication.


test
Highly Positive


These data indicate that elevated plasma AA delays the insulin response to a glucose challenge in normoglycemic adults, thereby prolonging the postprandial hyperglycemia. These effects might be partially explained by the competitive inhibition of glucose transfer into pancreatic beta cells by high concentrations of circulating AA.


test
Highly Positive


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


test
Highly Positive


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


test
Highly Positive


This is to our knowledge the first randomized trial in humans that has demonstrated that short-term vitamin C supplementation could significantly reduce resistin levels, independent of changes in inflammatory or metabolic variables. Future investigations of resistin participation in oxidative processes are warranted.


test
Highly Positive


Vitamin C did not affect plasma FFA concentrations. Glyceryl trinitrate responsiveness was unchanged during FFA elevation, with or without vitamin C. These data suggest that FFA-induced vascular oxidative stress could contribute to endothelial dysfunction in insulin-resistant patients. High concentrations of antioxidants are able to reverse the local effects of FFA on endothelium-dependent vasodilation.


  • Vitamin C for Weight loss

  • Vitamin C for Joint support

  • Vitamin C for Women's health

  • Vitamin C for Muscle building

test
Slightly Positive


Glutathione ratio (oxidized glutathione/total glutathione) was significantly increased at 4 and 24 h with P but VC prevented this change. These data suggest that vitamin C pretreatment can reduce MS, delay CK increase, and prevent blood glutathione oxidation with little influence on muscle function loss.


test
Slightly Positive


Nevertheless, downhill running provoked a similar increase in circulating markers of muscle damage (creatine kinase activity and myoglobin concentration) and muscle soreness in P and VC groups. Similarly, although downhill running increased plasma interleukin-6, there was no effect from VC supplementation. These results suggest that vitamin C supplementation does not affect interleukin-6 concentrations following eccentric exercise that has a low metabolic component.


test
Slightly Positive


The complete lack of any effect on the physiologic and biochemical outcome measures used raises questions about the validity of using oral antioxidant supplementation as a redox modulator of muscle and redox status in healthy humans.


test
Slightly Positive


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


test
Slightly Positive


These data provide preliminary evidence that vitamin C status may influence fatigue, heart rate, and perceptions of exertion during moderate exercise in obese individuals.


test
Slightly Positive


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


test
Slightly Positive


VC supplementation prevented endurance exercise-induced lipid peroxidation and muscle damage but had no effect on inflammatory markers.


test
Slightly Negative


Daily oral consumption of 1 g of vitamin C during a 4 wk high-intensity interval training period does not impair training-induced improvements in the exercise performance of recreationally active males.


test
Slightly Negative


Molecular mediators of endogenous ROS defense (superoxide dismutases 1 and 2; glutathione peroxidase) were also induced by exercise, and this effect too was blocked by antioxidant supplementation. Consistent with the concept of mitohormesis, exercise-induced oxidative stress ameliorates insulin resistance and causes an adaptive response promoting endogenous antioxidant defense capacity. Supplementation with antioxidants may preclude these health-promoting effects of exercise in humans.


  • Vitamin C for Emotional health

  • Vitamin C for Antioxidant potential

test
Slightly Positive


In conclusion, the results indicate that 400 IU/day of vitamin E reduces membrane damage more effectively than vitamin C but does not enhance performance. Athletes are encouraged to include antioxidants, such as vitamin E and C, in their diet to counteract these detrimental effects of exercise. The data presented here suggests that 400 IU/day of vitamin E will provide adequate protection but supplementing the diet with 1 g per day of vitamin C may promote cellular damage. However neither of these vitamins, either alone or in combination, will enhance exercise performance.


test
Slightly Positive


Data analysis was carried out using Mann-Whitney U test with p < 0.05 being significant by SPSS software version 16.The result of the study showed a significantly decrease in fasting (p = 0.006) and postprandial MDA (p < 0.001) in vitamin C group compare to placebo group but not in lipid profile. This study suggests that vitamin C supplementation can decrease fasting and postprandial oxidative stress and may prevent diabetes complication.


test
Slightly Positive


In conclusion, acute supplementation with a high dose of VC has little or no effect on the hormonal, interleukin-6, or immune response to prolonged exercise and combined ingestion of VC with CHO provides no additional effects compared with CHO alone.


test
Slightly Positive


In contrast, vitamin C supplementation decreased urinary concentrations of DHN-MA (three-way interaction p=0.0304) in nonsmoking men compared with nonsmoking women (p<0.05), as well as in nonsmoking men compared with smoking men (p<0.05). Vitamin C supplementation also decreased (p=0.0092) urinary total of metabolites by ~20%. Thus, HPNE metabolites can be reduced favorably in response to improved plasma ascorbic acid concentrations, an effect due to ascorbic acid antioxidant function.


test
Slightly Positive


In summary, oral AA supplementation ameliorates skeletal muscle oxidative stress during hyperinsulinaemia and improves insulin-mediated glucose disposal in people with type 2 diabetes. Findings implicate AA supplementation as a potentially inexpensive, convenient, and effective adjunct therapy in the treatment of insulin resistance in people with type 2 diabetes.


test
Slightly Positive


No significant correlations were found between post-race plasma vitamin C, oxidative, and saliva measures, except for a positive correlation between post-race serum cortisol and serum vitamin C (r=0.50, P=0.006). These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and sIgA changes during or following a competitive ultramarathon race.


test
Slightly Positive


Oral supplementation of vitamin C is not associated with changes in markers of oxidation or endothelial activation in healthy male smokers.


test
Slightly Positive


Our findings suggest that that administration of 1,000 mg of ascorbic acid together with 400 IU of alpha-tocopherol could be useful in preventing or aiding in the treatment of age-related osteoporosis.


test
Slightly Positive


These data indicate that the regular consumption of 8 fl. oz. orange juice or supplemental vitamin C ( approximately 70 mg/day) effectively reduced a marker of lipid peroxidation in plasma.


test
Slightly Positive


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


test
Slightly Positive


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


test
Slightly Positive


These findings suggest that administration of 1,000 mg of ascorbic acid plus 400 IU of alpha-tocopherol for 6 months is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.


test
Slightly Positive


Uric acid and TAC were decreased in group I on all measurement days. However, we did not observe any differences in the clinical status of patients receiving vitamin C during the first ten days of stroke or after 3 months. Although administration of vitamin C (500 mg/day, iv) to ischemic stroke patients since the first day ischemic stroke resulted in elevated serum levels of antioxidants, it did not substantially improve the clinical and functional status of patients after 3 months.


  • Vitamin C for Reproduction

  • Vitamin C for Insulin control

test
Slightly Positive


ACTH level was increased at the second and sixth hours, which was statistically significant, but at twelfth and twenty-forth hours, they were close to control group levels. As a result, we conclude that AA given before anaesthesia achieved by etomidate is not sufficient for the prevention of surgical stress response and that AA induction before anaesthesia should be preferred, particularly for the prevention of decrease in osteocalcin levels.


test
Slightly Positive


Fifty diabetic patients took part in a four-month, double-blind crossover study comparing 500 mg of vitamin C daily with placebo. No significant difference was observed between vitamin C and placebo therapy in fasting whole blood glucose, serum cholesterol, triglycerides, and glycosylated haemoglobin levels.


test
Slightly Positive


In conclusion, greater reduction in glucose concentrations observed in patients with diabetes, older individuals and with more prolonged supplementation. Personalised interventions with vitamin C may represent a feasible future strategy to enhance benefits and efficacy of interventions. Nevertheless, results need to be interpreted cautiously due to limitations in the primary studies analysed.


test
Slightly Positive


In conclusion, oral supplementation of vitamin C with metformin reverses ascorbic acid levels, reduces FBS, PMBG, and improves HbA1c. Hence, both the drugs in combination may be used in the treatment of type 2 DM to maintain good glycemic control.


test
Slightly Positive


In summary, it is concluded that, eight weeks of taking EPA + vitamin C supplementation improved the plasma levels of cardiovascular markers but didn't reduce BP.


test
Slightly Positive


In summary, oral AA supplementation ameliorates skeletal muscle oxidative stress during hyperinsulinaemia and improves insulin-mediated glucose disposal in people with type 2 diabetes. Findings implicate AA supplementation as a potentially inexpensive, convenient, and effective adjunct therapy in the treatment of insulin resistance in people with type 2 diabetes.


test
Slightly Positive


Individuals with type 2 diabetes experienced improved postprandial and 24-hour glycaemia and decreased BP after 4 months of AA supplementation as compared to placebo. These findings offer evidence for the proposed use of AA as an adjunct therapy to improve glycaemic and BP control in individuals with type 2 diabetes.


test
Slightly Positive


It is concluded that LC supplementation induces changes in blood glucose handling/disposal during an OGTT, which is not influenced by GLP-1. The glucose handling/disposal response to oral LC is different between lean and overweight/obese suggesting that further investigation is required. LC effects on gastric emptying and/or direct 'insulin-like' actions on tissues should be examined in larger samples of overweight/obese and lean participants, respectively.


test
Slightly Positive


No significant changes in fasting glucose (156 +/- 11 mg/dl), insulin (14 +/- 2 microU/ml), SI(Clamp) [2.71 +/- 0.46 x 10(-4) dl x kg(-1) x min(-1)/(microU/ml)], or forearm blood flow in response to ACh, SNP, or insulin were observed after vitamin C treatment. We conclude that high-dose oral vitamin C therapy, resulting in incomplete replenishment of vitamin C levels, is ineffective at improving endothelial dysfunction and insulin resistance in Type 2 diabetes.


test
Slightly Positive


No significant differences in any of the parameters measured were seen, when comparing results following AA or placebo treatment. The glomerular filtration rate (GFR, clearance of 125I-iothalamate) was unchanged while effective renal plasma flow (ERPF, clearance of 131I-hippuran) tended to decline in both groups.


test
Slightly Positive


Our study suggests that if vitamin C does have anti-atherosclerotic effects in diabetes, it does not exert them through the traditional pathways identifiable by established surrogate markers of cardiovascular risk.


test
Slightly Positive


The results demonstrated that Vitamin C may have beneficial effects on HDL-C in diabetic patients without significant effects on plasma glucose or other lipid parameters; however, its role for the treatment of low HDL-C patients should be evaluated in larger studies.


test
Slightly Positive


These data indicate that elevated plasma AA delays the insulin response to a glucose challenge in normoglycemic adults, thereby prolonging the postprandial hyperglycemia. These effects might be partially explained by the competitive inhibition of glucose transfer into pancreatic beta cells by high concentrations of circulating AA.


test
Slightly Positive


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


test
Slightly Positive


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


test
Slightly Positive


This is to our knowledge the first randomized trial in humans that has demonstrated that short-term vitamin C supplementation could significantly reduce resistin levels, independent of changes in inflammatory or metabolic variables. Future investigations of resistin participation in oxidative processes are warranted.


test
Slightly Positive


Vitamin C (500 mg twice daily) has potential effects in alleviating inflammatory status by reducing hs-CRP, IL-6, and FBG in hypertensive and/or diabetic obese patients.


test
Slightly Positive


Vitamin C did not affect plasma FFA concentrations. Glyceryl trinitrate responsiveness was unchanged during FFA elevation, with or without vitamin C. These data suggest that FFA-induced vascular oxidative stress could contribute to endothelial dysfunction in insulin-resistant patients. High concentrations of antioxidants are able to reverse the local effects of FFA on endothelium-dependent vasodilation.


  • Vitamin C for Energy

  • Vitamin C for Heart health

test
Slightly Positive


CI increased 40% after ascorbate as did peripheral flows. Peripheral resistances were increased (nearly double control) and decreased by nearly 50% after ascorbate. Calf capacitance and venous resistance were decreased compared with control but normalized with ascorbate. These data provide experimental support for the concept that oxidative stress and reduced NO possibly contribute to vasoconstriction and venoconstriction of LFP.


test
Slightly Positive


However, there was a significant beneficial effect of ascorbic acid on the FMD change over time after smoking. After smoking, the FMD dropped to less than half of the baseline value. Thereafter in the placebo group, FMD increased to 70% of baseline value in 90 minutes, but in the ascorbic acid group the FMD increased to 70% of baseline value in 46 minutes. Oral administration of ascorbic acid attenuates endothelial dysfunction after short-term cigarette smoking by shortening its duration.


test
Slightly Positive


In summary, it is concluded that, eight weeks of taking EPA + vitamin C supplementation improved the plasma levels of cardiovascular markers but didn't reduce BP.


test
Slightly Positive


Individuals with type 2 diabetes experienced improved postprandial and 24-hour glycaemia and decreased BP after 4 months of AA supplementation as compared to placebo. These findings offer evidence for the proposed use of AA as an adjunct therapy to improve glycaemic and BP control in individuals with type 2 diabetes.


test
Slightly Positive


It is concluded that LC supplementation induces changes in blood glucose handling/disposal during an OGTT, which is not influenced by GLP-1. The glucose handling/disposal response to oral LC is different between lean and overweight/obese suggesting that further investigation is required. LC effects on gastric emptying and/or direct 'insulin-like' actions on tissues should be examined in larger samples of overweight/obese and lean participants, respectively.


test
Slightly Positive


No significant changes in fasting glucose (156 +/- 11 mg/dl), insulin (14 +/- 2 microU/ml), SI(Clamp) [2.71 +/- 0.46 x 10(-4) dl x kg(-1) x min(-1)/(microU/ml)], or forearm blood flow in response to ACh, SNP, or insulin were observed after vitamin C treatment. We conclude that high-dose oral vitamin C therapy, resulting in incomplete replenishment of vitamin C levels, is ineffective at improving endothelial dysfunction and insulin resistance in Type 2 diabetes.


test
Slightly Positive


No significant differences in any of the parameters measured were seen, when comparing results following AA or placebo treatment. The glomerular filtration rate (GFR, clearance of 125I-iothalamate) was unchanged while effective renal plasma flow (ERPF, clearance of 131I-hippuran) tended to decline in both groups.


test
Slightly Positive


Oral glucose load impairs endothelium dependent dilation and hyperaemia at microcirculation, probably via oxidative stress; ascorbic acid can prevent it.


test
Slightly Positive


Our study suggests that if vitamin C does have anti-atherosclerotic effects in diabetes, it does not exert them through the traditional pathways identifiable by established surrogate markers of cardiovascular risk.


test
Slightly Positive


The vitamin E effect was not significant. In summary, treatment with vitamin C but not vitamin E significantly reduced CRP among individuals with CRP > or =1.0 mg/L. Among the obese, 75% had CRP > or =1.0 mg/L. Research is needed to determine whether reducing this inflammatory biomarker with vitamin C could reduce diseases associated with obesity. But research on clinical benefits of antioxidants should limit participants to persons with elevations in the target biomarkers.


test
Slightly Positive


Therefore, ascorbic acid may have potential therapeutic use in clinical situations where acute hyperglycaemia may be a complication.


test
Slightly Positive


This is to our knowledge the first randomized trial in humans that has demonstrated that short-term vitamin C supplementation could significantly reduce resistin levels, independent of changes in inflammatory or metabolic variables. Future investigations of resistin participation in oxidative processes are warranted.


test
Slightly Positive


Vitamin C (500 mg twice daily) has potential effects in alleviating inflammatory status by reducing hs-CRP, IL-6, and FBG in hypertensive and/or diabetic obese patients.


test
Slightly Positive


Vitamin C did not affect plasma FFA concentrations. Glyceryl trinitrate responsiveness was unchanged during FFA elevation, with or without vitamin C. These data suggest that FFA-induced vascular oxidative stress could contribute to endothelial dysfunction in insulin-resistant patients. High concentrations of antioxidants are able to reverse the local effects of FFA on endothelium-dependent vasodilation.


test
Slightly Positive


VitC supplementation reduced the MBP and restored peripheral vasodilatation response during mental stress in obese children.


test
Slightly Negative


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


test
Slightly Negative


These data provide preliminary evidence that vitamin C status may influence fatigue, heart rate, and perceptions of exertion during moderate exercise in obese individuals.


test
Slightly Negative


These data suggest that vitamin C supplementation can decrease postexercise cortisol in individuals performing exercise similar to that of a half-marathon or marathon in hot conditions. However, no changes in s-IgA and URTI were evident, possibly due to previous moderate training and reduced physical and psychological stress compared with athletes participating in ultramarathons.


test
Slightly Negative


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.



What are Vitamin C's effects on the body?

  • Vitamin C for the Immune System

AA appears to increase FSI, and the differential benefit to noncohabitants suggests that a central activation or disinhibition, rather than peripheral mechanism may be responsible.


Fifty diabetic patients took part in a four-month, double-blind crossover study comparing 500 mg of vitamin C daily with placebo. No significant difference was observed between vitamin C and placebo therapy in fasting whole blood glucose, serum cholesterol, triglycerides, and glycosylated haemoglobin levels.


In conclusion, oral supplementation of vitamin C with metformin reverses ascorbic acid levels, reduces FBS, PMBG, and improves HbA1c. Hence, both the drugs in combination may be used in the treatment of type 2 DM to maintain good glycemic control.


No significant changes in fasting glucose (156 +/- 11 mg/dl), insulin (14 +/- 2 microU/ml), SI(Clamp) [2.71 +/- 0.46 x 10(-4) dl x kg(-1) x min(-1)/(microU/ml)], or forearm blood flow in response to ACh, SNP, or insulin were observed after vitamin C treatment. We conclude that high-dose oral vitamin C therapy, resulting in incomplete replenishment of vitamin C levels, is ineffective at improving endothelial dysfunction and insulin resistance in Type 2 diabetes.


No significant correlations were found between post-race plasma vitamin C, oxidative, and saliva measures, except for a positive correlation between post-race serum cortisol and serum vitamin C (r=0.50, P=0.006). These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and sIgA changes during or following a competitive ultramarathon race.


Therefore, ascorbic acid may have potential therapeutic use in clinical situations where acute hyperglycaemia may be a complication.


These data indicate that elevated plasma AA delays the insulin response to a glucose challenge in normoglycemic adults, thereby prolonging the postprandial hyperglycemia. These effects might be partially explained by the competitive inhibition of glucose transfer into pancreatic beta cells by high concentrations of circulating AA.


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


This is to our knowledge the first randomized trial in humans that has demonstrated that short-term vitamin C supplementation could significantly reduce resistin levels, independent of changes in inflammatory or metabolic variables. Future investigations of resistin participation in oxidative processes are warranted.


Vitamin C did not affect plasma FFA concentrations. Glyceryl trinitrate responsiveness was unchanged during FFA elevation, with or without vitamin C. These data suggest that FFA-induced vascular oxidative stress could contribute to endothelial dysfunction in insulin-resistant patients. High concentrations of antioxidants are able to reverse the local effects of FFA on endothelium-dependent vasodilation.


  • Vitamin C for the Digestive System

  • Vitamin C for the Cardiovascular System

CI increased 40% after ascorbate as did peripheral flows. Peripheral resistances were increased (nearly double control) and decreased by nearly 50% after ascorbate. Calf capacitance and venous resistance were decreased compared with control but normalized with ascorbate. These data provide experimental support for the concept that oxidative stress and reduced NO possibly contribute to vasoconstriction and venoconstriction of LFP.


However, there was a significant beneficial effect of ascorbic acid on the FMD change over time after smoking. After smoking, the FMD dropped to less than half of the baseline value. Thereafter in the placebo group, FMD increased to 70% of baseline value in 90 minutes, but in the ascorbic acid group the FMD increased to 70% of baseline value in 46 minutes. Oral administration of ascorbic acid attenuates endothelial dysfunction after short-term cigarette smoking by shortening its duration.


In summary, it is concluded that, eight weeks of taking EPA + vitamin C supplementation improved the plasma levels of cardiovascular markers but didn't reduce BP.


Individuals with type 2 diabetes experienced improved postprandial and 24-hour glycaemia and decreased BP after 4 months of AA supplementation as compared to placebo. These findings offer evidence for the proposed use of AA as an adjunct therapy to improve glycaemic and BP control in individuals with type 2 diabetes.


It is concluded that LC supplementation induces changes in blood glucose handling/disposal during an OGTT, which is not influenced by GLP-1. The glucose handling/disposal response to oral LC is different between lean and overweight/obese suggesting that further investigation is required. LC effects on gastric emptying and/or direct 'insulin-like' actions on tissues should be examined in larger samples of overweight/obese and lean participants, respectively.


No significant changes in fasting glucose (156 +/- 11 mg/dl), insulin (14 +/- 2 microU/ml), SI(Clamp) [2.71 +/- 0.46 x 10(-4) dl x kg(-1) x min(-1)/(microU/ml)], or forearm blood flow in response to ACh, SNP, or insulin were observed after vitamin C treatment. We conclude that high-dose oral vitamin C therapy, resulting in incomplete replenishment of vitamin C levels, is ineffective at improving endothelial dysfunction and insulin resistance in Type 2 diabetes.


No significant differences in any of the parameters measured were seen, when comparing results following AA or placebo treatment. The glomerular filtration rate (GFR, clearance of 125I-iothalamate) was unchanged while effective renal plasma flow (ERPF, clearance of 131I-hippuran) tended to decline in both groups.


Oral glucose load impairs endothelium dependent dilation and hyperaemia at microcirculation, probably via oxidative stress; ascorbic acid can prevent it.


Our study suggests that if vitamin C does have anti-atherosclerotic effects in diabetes, it does not exert them through the traditional pathways identifiable by established surrogate markers of cardiovascular risk.


The vitamin E effect was not significant. In summary, treatment with vitamin C but not vitamin E significantly reduced CRP among individuals with CRP > or =1.0 mg/L. Among the obese, 75% had CRP > or =1.0 mg/L. Research is needed to determine whether reducing this inflammatory biomarker with vitamin C could reduce diseases associated with obesity. But research on clinical benefits of antioxidants should limit participants to persons with elevations in the target biomarkers.


Therefore, ascorbic acid may have potential therapeutic use in clinical situations where acute hyperglycaemia may be a complication.


This is to our knowledge the first randomized trial in humans that has demonstrated that short-term vitamin C supplementation could significantly reduce resistin levels, independent of changes in inflammatory or metabolic variables. Future investigations of resistin participation in oxidative processes are warranted.


Vitamin C (500 mg twice daily) has potential effects in alleviating inflammatory status by reducing hs-CRP, IL-6, and FBG in hypertensive and/or diabetic obese patients.


Vitamin C did not affect plasma FFA concentrations. Glyceryl trinitrate responsiveness was unchanged during FFA elevation, with or without vitamin C. These data suggest that FFA-induced vascular oxidative stress could contribute to endothelial dysfunction in insulin-resistant patients. High concentrations of antioxidants are able to reverse the local effects of FFA on endothelium-dependent vasodilation.


VitC supplementation reduced the MBP and restored peripheral vasodilatation response during mental stress in obese children.


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


These data provide preliminary evidence that vitamin C status may influence fatigue, heart rate, and perceptions of exertion during moderate exercise in obese individuals.


These data suggest that vitamin C supplementation can decrease postexercise cortisol in individuals performing exercise similar to that of a half-marathon or marathon in hot conditions. However, no changes in s-IgA and URTI were evident, possibly due to previous moderate training and reduced physical and psychological stress compared with athletes participating in ultramarathons.


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


  • Vitamin C for the Endocrine System

ACTH level was increased at the second and sixth hours, which was statistically significant, but at twelfth and twenty-forth hours, they were close to control group levels. As a result, we conclude that AA given before anaesthesia achieved by etomidate is not sufficient for the prevention of surgical stress response and that AA induction before anaesthesia should be preferred, particularly for the prevention of decrease in osteocalcin levels.


Fifty diabetic patients took part in a four-month, double-blind crossover study comparing 500 mg of vitamin C daily with placebo. No significant difference was observed between vitamin C and placebo therapy in fasting whole blood glucose, serum cholesterol, triglycerides, and glycosylated haemoglobin levels.


In conclusion, greater reduction in glucose concentrations observed in patients with diabetes, older individuals and with more prolonged supplementation. Personalised interventions with vitamin C may represent a feasible future strategy to enhance benefits and efficacy of interventions. Nevertheless, results need to be interpreted cautiously due to limitations in the primary studies analysed.


In conclusion, oral supplementation of vitamin C with metformin reverses ascorbic acid levels, reduces FBS, PMBG, and improves HbA1c. Hence, both the drugs in combination may be used in the treatment of type 2 DM to maintain good glycemic control.


In summary, it is concluded that, eight weeks of taking EPA + vitamin C supplementation improved the plasma levels of cardiovascular markers but didn't reduce BP.


In summary, oral AA supplementation ameliorates skeletal muscle oxidative stress during hyperinsulinaemia and improves insulin-mediated glucose disposal in people with type 2 diabetes. Findings implicate AA supplementation as a potentially inexpensive, convenient, and effective adjunct therapy in the treatment of insulin resistance in people with type 2 diabetes.


Individuals with type 2 diabetes experienced improved postprandial and 24-hour glycaemia and decreased BP after 4 months of AA supplementation as compared to placebo. These findings offer evidence for the proposed use of AA as an adjunct therapy to improve glycaemic and BP control in individuals with type 2 diabetes.


It is concluded that LC supplementation induces changes in blood glucose handling/disposal during an OGTT, which is not influenced by GLP-1. The glucose handling/disposal response to oral LC is different between lean and overweight/obese suggesting that further investigation is required. LC effects on gastric emptying and/or direct 'insulin-like' actions on tissues should be examined in larger samples of overweight/obese and lean participants, respectively.


No significant changes in fasting glucose (156 +/- 11 mg/dl), insulin (14 +/- 2 microU/ml), SI(Clamp) [2.71 +/- 0.46 x 10(-4) dl x kg(-1) x min(-1)/(microU/ml)], or forearm blood flow in response to ACh, SNP, or insulin were observed after vitamin C treatment. We conclude that high-dose oral vitamin C therapy, resulting in incomplete replenishment of vitamin C levels, is ineffective at improving endothelial dysfunction and insulin resistance in Type 2 diabetes.


No significant differences in any of the parameters measured were seen, when comparing results following AA or placebo treatment. The glomerular filtration rate (GFR, clearance of 125I-iothalamate) was unchanged while effective renal plasma flow (ERPF, clearance of 131I-hippuran) tended to decline in both groups.


Our study suggests that if vitamin C does have anti-atherosclerotic effects in diabetes, it does not exert them through the traditional pathways identifiable by established surrogate markers of cardiovascular risk.


The results demonstrated that Vitamin C may have beneficial effects on HDL-C in diabetic patients without significant effects on plasma glucose or other lipid parameters; however, its role for the treatment of low HDL-C patients should be evaluated in larger studies.


These data indicate that elevated plasma AA delays the insulin response to a glucose challenge in normoglycemic adults, thereby prolonging the postprandial hyperglycemia. These effects might be partially explained by the competitive inhibition of glucose transfer into pancreatic beta cells by high concentrations of circulating AA.


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


This is to our knowledge the first randomized trial in humans that has demonstrated that short-term vitamin C supplementation could significantly reduce resistin levels, independent of changes in inflammatory or metabolic variables. Future investigations of resistin participation in oxidative processes are warranted.


Vitamin C (500 mg twice daily) has potential effects in alleviating inflammatory status by reducing hs-CRP, IL-6, and FBG in hypertensive and/or diabetic obese patients.


Vitamin C did not affect plasma FFA concentrations. Glyceryl trinitrate responsiveness was unchanged during FFA elevation, with or without vitamin C. These data suggest that FFA-induced vascular oxidative stress could contribute to endothelial dysfunction in insulin-resistant patients. High concentrations of antioxidants are able to reverse the local effects of FFA on endothelium-dependent vasodilation.


  • Vitamin C for the Overall Systems

In conclusion, the results indicate that 400 IU/day of vitamin E reduces membrane damage more effectively than vitamin C but does not enhance performance. Athletes are encouraged to include antioxidants, such as vitamin E and C, in their diet to counteract these detrimental effects of exercise. The data presented here suggests that 400 IU/day of vitamin E will provide adequate protection but supplementing the diet with 1 g per day of vitamin C may promote cellular damage. However neither of these vitamins, either alone or in combination, will enhance exercise performance.


Data analysis was carried out using Mann-Whitney U test with p < 0.05 being significant by SPSS software version 16.The result of the study showed a significantly decrease in fasting (p = 0.006) and postprandial MDA (p < 0.001) in vitamin C group compare to placebo group but not in lipid profile. This study suggests that vitamin C supplementation can decrease fasting and postprandial oxidative stress and may prevent diabetes complication.


In conclusion, acute supplementation with a high dose of VC has little or no effect on the hormonal, interleukin-6, or immune response to prolonged exercise and combined ingestion of VC with CHO provides no additional effects compared with CHO alone.


In contrast, vitamin C supplementation decreased urinary concentrations of DHN-MA (three-way interaction p=0.0304) in nonsmoking men compared with nonsmoking women (p<0.05), as well as in nonsmoking men compared with smoking men (p<0.05). Vitamin C supplementation also decreased (p=0.0092) urinary total of metabolites by ~20%. Thus, HPNE metabolites can be reduced favorably in response to improved plasma ascorbic acid concentrations, an effect due to ascorbic acid antioxidant function.


In summary, oral AA supplementation ameliorates skeletal muscle oxidative stress during hyperinsulinaemia and improves insulin-mediated glucose disposal in people with type 2 diabetes. Findings implicate AA supplementation as a potentially inexpensive, convenient, and effective adjunct therapy in the treatment of insulin resistance in people with type 2 diabetes.


No significant correlations were found between post-race plasma vitamin C, oxidative, and saliva measures, except for a positive correlation between post-race serum cortisol and serum vitamin C (r=0.50, P=0.006). These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and sIgA changes during or following a competitive ultramarathon race.


Oral supplementation of vitamin C is not associated with changes in markers of oxidation or endothelial activation in healthy male smokers.


Our findings suggest that that administration of 1,000 mg of ascorbic acid together with 400 IU of alpha-tocopherol could be useful in preventing or aiding in the treatment of age-related osteoporosis.


These data indicate that the regular consumption of 8 fl. oz. orange juice or supplemental vitamin C ( approximately 70 mg/day) effectively reduced a marker of lipid peroxidation in plasma.


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


These findings suggest that administration of 1,000 mg of ascorbic acid plus 400 IU of alpha-tocopherol for 6 months is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.


Uric acid and TAC were decreased in group I on all measurement days. However, we did not observe any differences in the clinical status of patients receiving vitamin C during the first ten days of stroke or after 3 months. Although administration of vitamin C (500 mg/day, iv) to ischemic stroke patients since the first day ischemic stroke resulted in elevated serum levels of antioxidants, it did not substantially improve the clinical and functional status of patients after 3 months.


  • Vitamin C for the Muscular System

Glutathione ratio (oxidized glutathione/total glutathione) was significantly increased at 4 and 24 h with P but VC prevented this change. These data suggest that vitamin C pretreatment can reduce MS, delay CK increase, and prevent blood glutathione oxidation with little influence on muscle function loss.


Nevertheless, downhill running provoked a similar increase in circulating markers of muscle damage (creatine kinase activity and myoglobin concentration) and muscle soreness in P and VC groups. Similarly, although downhill running increased plasma interleukin-6, there was no effect from VC supplementation. These results suggest that vitamin C supplementation does not affect interleukin-6 concentrations following eccentric exercise that has a low metabolic component.


The complete lack of any effect on the physiologic and biochemical outcome measures used raises questions about the validity of using oral antioxidant supplementation as a redox modulator of muscle and redox status in healthy humans.


These data indicate that vitamin C supplementation in carbohydrate-fed runners does not serve as a countermeasure to oxidative and immune changes during or after a competitive ultramarathon race.


These data provide preliminary evidence that vitamin C status may influence fatigue, heart rate, and perceptions of exertion during moderate exercise in obese individuals.


These findings are the first to suggest that oral vitamin C supplementation provides an effective prophylaxis against exercise-induced free radical-mediated lipid peroxidation in human diabetic blood.


VC supplementation prevented endurance exercise-induced lipid peroxidation and muscle damage but had no effect on inflammatory markers.


Daily oral consumption of 1 g of vitamin C during a 4 wk high-intensity interval training period does not impair training-induced improvements in the exercise performance of recreationally active males.


Molecular mediators of endogenous ROS defense (superoxide dismutases 1 and 2; glutathione peroxidase) were also induced by exercise, and this effect too was blocked by antioxidant supplementation. Consistent with the concept of mitohormesis, exercise-induced oxidative stress ameliorates insulin resistance and causes an adaptive response promoting endogenous antioxidant defense capacity. Supplementation with antioxidants may preclude these health-promoting effects of exercise in humans.


  • Vitamin C for the Skeletal System

  • Vitamin C for the Nervous System

  • Vitamin C for the Reproductive System

Scroll to top