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The Vitamin C Foundation monitors research and news reports from around the world concerning vitamin C – ascorbic acid. We have been surprised by the number and frequency of recent positive reports. The links to these reports can be found on our main Web page, VitaminCFoundation.org.
Researchers Stop Diabetes Damage with High Vitamin C
Researchers at the Harold Hamm Oklahoma Diabetes Center, Oklahoma City, have found a way to stop the damage caused by type 1 diabetes with the combination of insulin and a common vitamin found in most medicine cabinets. While neither therapy produced desired results when used alone, the combination of insulin to control blood sugar together with the use of Vitamin C, stopped blood vessel damage caused by the disease in patients with poor glucose control. The findings appear in the Journal of Clinical Endocrinology and Metabolism [June 2, 2009] and will be presented at the upcoming American Diabetes Association international conference in New Orleans.
"We had tested this theory on research models, but this is the first time anyone has shown the therapy's effectiveness in people," said Michael Ihnat, PhD, principal investigator and a pharmacologist at the OU College of Medicine Department of Cell Biology.
Ihnat said they are now studying the therapy in patients with Type 2 diabetes.
The goal of the work being done by Ihnat and British scientists, led by Dr. Antonio Ceriello, from the University of Warwick is to find a way to stop the damage to blood vessels that is caused by diabetes. The damage, known as endothelial dysfunction, is associated with most forms of cardiovascular disease such as hypertension, coronary artery disease, chronic heart failure, peripheral artery disease, diabetes and chronic renal failure.
By reducing or stopping the damage, patients with diabetes could avoid some of the painful and fatal consequences of the disease that include heart disease, reduced circulation and amputation, kidney disease and diabetic retinopathy, which can lead to blindness.
Insulin and many other drugs have long been used to control blood sugar, but Ihnat – in an earlier project with scientists in Italy and Hungary – found that cells have a "memory" that causes damage to continue even when blood sugar is controlled. By adding antioxidants like Vitamin C, Ihnat found that cell "memory" disappeared and cell function and oxidation stress were normalized.
"We have speculated that this happens with endothelial dysfunction, but we did not know until now if it was effective in humans. We finally were able to test it and proved it to be true," Ihnat said. "For patients with diabetes, this means simply getting their glucose under control is not enough. An antioxidant-based therapy combined with glucose control will give patients more of an advantage and lessen the chance of complications with diabetes."
While researchers do suggest diabetic patients eat foods and take multivitamins rich in antioxidants like Vitamin C, they warn that additional study is needed. The Vitamin C utilized in their study was given at very high doses and administered directly into the blood stream, so it is unlikely someone would get similar results with an over-the-counter vitamin supplement.
The team is now working to determine how antioxidants work at the molecular level to halt the destructive chain reaction set in motion by high blood sugar levels. In addition, they are evaluating several other antioxidants with an ultimate hope that their work will translate into simple, effective and inexpensive treatments for the control of diabetes.
Dr. Ihnat's latest work, which is funded by the VA Medical Center, can be found online at http://jcem.endojournals.org/cgi/content/abstract/jc.2009-0762v1.
– The Norman Transcript
Men Who Take Vitamin C Supplements Are Less Likely to Develop Gout
Researchers at the University of British Columbia (Vancouver, Canada) found that men with higher intakes of vitamin C were less likely to develop the condition than men with lower levels. The research is based on almost 47,000 men who completed questionnaires on diet and vitamin C intake between 1986 and 2006. During 20 years of follow-up, 1,317 men developed gout.
Men who consumed between 500 milligrams and 999 milligrams of vitamin C a day had a 17% lower risk of developing gout than those who consumed less than 250 milligrams a day. For every 500-milligram increase in their vitamin C intake, men's risk for gout appeared to decrease by 17%. Compared with men who did not take vitamin C supplements, those who took 1,000 to 1,499 supplemental milligrams per day had a 34% lower risk of gout and those who took 1,500 supplemental milligrams per day had a 45% lower risk.
In the UK, the Food Standards Agency has not set an upper maximum recommended limit on vitamin C intake, but studies have suggested gastrointestinal discomfort with doses of between 1,000 mg and 3000 mg a day depending on body weight.
In the UK, gout affects around one in 200 adults, with men more commonly affected than women. The first attack normally occurs in middle age and it can run in families.
Lead author Dr Hyon Choi said: "Gout is the most common type of inflammatory arthritis in men.
"Epidemiologic studies suggest that the overall disease burden of gout is substantial and growing. The identification of the risk factors for gout that are modifiable with available measures is an important first step in the prevention and management of this common and excruciatingly painful condition."
Vitamin C appears to reduce levels of uric acid in the blood, by encouraging the kidneys to remove it, the authors said.
Dr Choi said: "Given the general safety profile associated with vitamin C intake, particularly in the generally consumed ranges as in the present study (e.g., tolerable upper intake level of vitamin C of less than 2,000 milligrams in adults according to the Food and Nutrition Board, Institute of Medicine), vitamin C intake may provide a useful option in the prevention of gout."
Low Vitamin A, C, and E Intake Increases Asthma Risk
(HealthDay News) People who don't get enough of the antioxidant vitamins A and C in their diet may be at increased risk for asthma, British researchers say. The pooled results of 40 studies conducted between 1980 and 2007 showed that people with asthma had a significantly lower dietary intake of vitamin A than those without the disease. The average intake among those with asthma was 182 micrograms a day, which is between a quarter and a third of recommended daily intake.
The review authors also found that people with severe asthma had a significantly lower intake of vitamin C (about half the recommended daily intake) than those with mild asthma. In addition, low circulating levels of vitamin C in the blood and lower dietary intake of foods containing vitamin C were associated with a 12% increased risk of asthma.
There was no association between vitamin E intake and asthma risk, but blood levels of vitamin E were much lower among people with severe asthma than in those with mild asthma. Those with severe asthma had an average vitamin E intake of 2 milligrams/day, which is 20% lower than the daily recommended amount, the review authors said.
These findings don't prove cause and effect, but they do challenge a study published last year that found no association between antioxidants and asthma risk, said Dr. Jo Leonardi-Bee, of the division of epidemiology and public health at the University of Nottingham in the United Kingdom, and colleagues.
"Overall, our findings from [the current] systematic review and meta-analysis indicate that low levels of vitamin C intake, and to a lesser extent vitamin A, are consistently associated with asthma risk to a degree that, if causal, would be sufficient to be clinically relevant," they concluded.
Their findings for an association between dietary antioxidants and wheezing were less consistent. The report was published in the current issue of Thorax.
Higher Plasma Vitamin C Levels Linked with Lower Diabetes Risk
In the American Medical Association journal (July 28, 2008), researchers at Addenbrooke’s Hospital and the University of Cambridge in England report an association between higher plasma vitamin C levels in middle-aged adults and a lower risk of developing type 2 diabetes.
The study included 21,831 healthy, nondiabetic participants in the European Prospective Investigation of Cancer-Norfolk study, which was created to examine the association between diet and cancer. Vitamin C levels were measured in plasma, and food frequency questionnaires were administered upon enrollment between 1993 and 1997. Over a 12-year follow-up period, 423 men and 312 women developed diabetes.
Analysis of the data revealed a strong protective effect of high vitamin C levels against diabetes. Participants in the top 20% of plasma vitamin C had a 62% lower adjusted risk of developing diabetes compared with those in the lowest fifth. Fruit and vegetable intake also emerged as protective. Those whose intake was in the top fifth had a 22% lower diabetes risk than subjects whose intake was lowest.
To the authors’ knowledge, the study is the first to examine the association of plasma vitamin C and the development of diabetes. The findings suggest that suboptimal levels of vitamin C are present before the onset of the disease.
Increased oxidative stress, defined as an imbalance between reactive oxygen species levels and antioxidants, can result in glucose metabolism disturbances and elevated blood sugar. The authors write that the abundant phytochemicals, minerals, and vitamins, including vitamin C, in fruit and vegetables have antioxidant properties that may be responsible for the protective effect against diabetes observed in the current study. Additionally, individuals whose fruit and vegetable intake is greater tend to have lower levels of obesity, which is a strong risk factor for diabetes as well as a promoter of oxidative stress.
"The strong independent association observed in this prospective study, together with biological plausibility, provides persuasive evidence of a beneficial effect of vitamin C and fruit and vegetable intake on diabetes risk," the authors conclude. "Because fruit and vegetables are the main sources of vitamin C, the findings suggest that eating even a small quantity of fruit and vegetables may be beneficial and that the protection against diabetes increases progressively with the quantity of fruit and vegetables consumed."
– Life Extension
Vitamin C Stops the Growth of Cancerous Tumors in Mice
The study was lead by Chi Dang, MD, PhD, professor of medicine and oncology and Johns Hopkins Family Professor in Oncology Research (Cancer Cell; 11 September, 2007;12:230–238). They found that the antioxidants' actual role may be to destabilize a tumor's ability to grow under conditions where there isn't enough oxygen to feed it.
The conventional belief is that vitamin C helps prevent cancer growth by grabbing up volatile oxygen free radical molecules and preventing the damage they do to our DNA. "The potential anticancer benefits of antioxidants have been the driving force for many clinical and preclinical studies," says Dang. "By uncovering the mechanism behind antioxidants, we are now better suited to maximize their therapeutic use."
The researchers caution that while vitamin C is crucial to our health, you should not rush out and buy antioxidant supplements in bulk just to prevent cancer. This study is only preliminary and more research will be needed. The researchers discovered the antioxidant mechanism while looking at mice that had been implanted with human lymphoma (blood cancer) or human liver cancer cells. Both cancers produce high levels of free radicals; they found that they could suppress the free radicals by feeding the mice supplements of vitamin C or N- acetylcysteine (NAC), both powerful antioxidants.
When the researchers examined the cancer cells from the diseased mice not fed the antioxidants, they noticed that their DNA had not been significantly damaged. "Clearly, if DNA damage was not in play as a cause of the cancer, then whatever the antioxidants were doing to help was also not related to DNA damage," says Ping Gao, PhD. This discovery led Gao and Dang to suspect that other factors were involved, such as a protein called HIF-1 (hypoxia-induced factor). They found that this protein disappeared in mice that received vitamin C treatment; it is usually abundant in untreated cancer cells.
"When a cell lacks oxygen, HIF-1 helps it compensate," explains Dang. "HIF-1 helps an oxygen-starved cell convert sugar to energy without using oxygen and also initiates the construction of new blood vessels to bring in a fresh oxygen supply."
Fast-growing tumors can consume enough energy to effortlessly suck the available oxygen from everything that is close to them, thus making HIF-1 crucial for survival. HIF-1 can only function normally if it has fuel to keep it going; it needs free radicals. The researchers found that antioxidants remove the free radicals, thus stopping HIF-1, and the tumor.
They confirmed the importance of the hypoxia protein by creating cancer cells with a variant of HIF-1 that did not require free radicals to function. In these cells antioxidants had zero effect on the cancer.
– Natural News.com
Vitamin C Has Crucial Anti-Aging Properties: Study
Allahabad (PTI): Acknowledged as a nutrient vital for a robust immune system, Vitamin C may also be crucial for slowing down the human body's aging process, says a study. The study published in the latest edition of the American journal Rejuvenation Research has underscored a protective mechanism in the human body aimed at maintaining the level of ascorbic acid (chemical name for vitamin C) in blood plasma, which invariably keeps falling with age. "Studies in the last 50 years have identified oxidative stress, a condition marked by increasing damage to the immune system from molecules known as free radicals, as one of the main reasons for the process of aging," Prof. Syed Ibrahim Rizvi, the lead researcher of the paper, told PTI.
Rizvi, who is a professor of biochemistry at the Allahabad University, said the human body "is endowed with several antioxidant defense mechanisms to minimize damage from free radicals. Vitamin C happens to be one of the most important among such defense mechanisms.
"This was one of the reasons why scientists like Prof Linus Pauling, Nobel Laureate and one of the most influential chemists of the 20th century, advocated large doses of vitamin C in the diet for prevention of common cold and boosting the overall immunity system of the human body," he said.
Vitamin C Improves Dark Circles
Japanese researchers have found that vitamin C may improve dark circles of the lower eyelid (DCLE) by thickening the eyelid dermis and concealing dark coloration due to congested blood (Skin Res Technol. 2009;15:214–217). A total of 14 subjects with DCLE applied either 10% sodium ascorbate (ANa) or ascorbic acid glucoside (AG) lotion in split-face fashion (opposite side: vehicle only) for six months. Change in erythema index was significantly smaller on the ANa-treated side than on the vehicle-treated side. Dermal thickness tended to be thicker for the ANa-treated side than for the vehicle-treated side, although no significant difference was seen. Both erythema index and dermal thickness tended to change in parallel manner. On the other hand, no significant differences in changes of erythema index, melanin index, and dermal thickness were found between AG- and vehicle-treated sides.
– Inside Cosmeceuticals
Vitamin C and Blood Pressure Linked
A study published in Nutrition Journal found that young women who take in the most vitamin C have the healthiest blood pressure stats. The study followed 242 women between 18 and 21 years old for a 10-year period. At the conclusion of the study, researchers found that the blood pressure of women with the highest levels of vitamin C was an average of four points lower than women with the least amount of vitamin C.
Study coauthor Gladys Block, PhD, said that the vitamin C reduces inflammation in the body by decreasing the amount of C-reactive protein in the blood. The authors concluded that "vitamin C may be an important factor in BP regulation even among healthy young adults, and that further study is warranted."
– China Daily
Mega-C Reduced Colds/Flu 85% (Clinical Study)
This is a little known 1999 clinical study which monitored more correct (higher) dosages of vitamin C than most: "The effectiveness of vitamin C in preventing and relieving the symptoms of virus-induced respiratory infections."
Results: Overall, reported flu and cold symptoms in the test group decreased 85% compared with the control group after the administration of megadose Vitamin C.
Conclusion: Vitamin C in megadoses administered before or after the appearance of cold and flu symptoms relieved and prevented the symptoms in the test population compared with the control group.
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