Why is vitamin C so important for our health?

Vitamin C is found in many fruits and vegetables. Skin care and anti-ageing products also often contain this powerful micronutrient, which we all need so urgently. Studies confirm that vitamin C has many benefits for our health.

Our body has difficulty compensating for a vitamin C deficiency. Symptoms then appear such as

• a weakened immune system
• Inflammation of the gums
• a tendency to bruise

Conversely, the following applies: With a sufficient vitamin C intake:

• strengthen your immune system
• protect themselves from diseases and infections
• improve iron absorption
• even reduce your risk of painful diseases such as gout

Contents

• What is vitamin C?
• What does the body need vitamin C for?
• How can the daily requirement of vitamin C be covered?
• Which foods contain the most vitamin C?
• What are the symptoms of a vitamin C deficiency?
• What is the role of vitamin C?
• Can vitamin C be overdosed?
• How much vitamin C should I take?
• Linus Pauling - "The vitamin C man"

What is vitamin C?

Vitamin C, also known as ascorbic acid, is a water-soluble vitamin that is found in many types of fruit and vegetables. It acts as an antioxidant, neutralizes free radicals and reduces the risk of inflammation and disease.

The body also uses vitamin C to synthesize important compounds such as collagen. This is a structural protein that is needed to build connective tissue and supports wound healing. Vitamin C is also used to form other compounds, such as L-carnitine and various neurotransmitters.

Ongoing scientific studies are revealing the far-reaching potential of vitamin C. An adequate intake can improve skin health, strengthen the immune system and protect against certain diseases.

 

What does the body need vitamin C for?

Vitamin C has two important functions that explain the extensive benefits for our health.

• First of all, it acts as an effective antioxidant. Vitamin C is also a co-factor in enzymatic processes.
• It is also considered a "reducing agent". This means that it donates electrons to other molecules and thus reduces oxidation.

The Linus Pauling Institute explains it as follows:

"Vitamin C is the most important water-soluble, non-enzymatic antioxidant in plasma and tissue. Even in small amounts, vitamin C can protect essential molecules in the body - proteins, lipids (fats), carbohydrates and nucleic acids (DNA and RNA) - from damage caused by free radicals and reactive oxygen species (ROS). Both are produced during normal metabolic processes, by active immune cells and by toxins and environmental pollutants..."

Vitamin C also supports the regeneration of vitamin E from its oxidized form and is involved in the metabolism of cholesterol to bile acid. This lowers cholesterol levels and prevents gallstones. Vitamin C also strengthens the body's ability to absorb iron from food and plays a role in detoxification. It can neutralize and eliminate a number of toxins in the body.

How can the daily requirement of vitamin C be covered?

How much vitamin C you need per day varies depending on age and gender, the corresponding energy requirement and many other factors, such as environmental or psychological stress or illness. The daily vitamin C requirement may be higher during breastfeeding.

The best way to replenish your vitamin C stores is to eat whole, fresh organic foods from your region, primarily fruit and vegetables. Many people, especially numerous naturopaths, are convinced that ascorbic acid alone is not enough. They believe in the synergistic effects of ascorbic acid together with associated micronutrients such as bioflavonoids and other compounds. This is the only way to get the full range of benefits.

With a varied diet (e.g. plenty of vegetables) you can achieve these synergy effects of the various phytonutrients quite naturally. We have compiled a list of good sources of vitamin C below. Or you can simply squeeze a fresh lemon and lime and add the juice to your water. This will give you a refreshing thirst quencher with plenty of vitamin C.

Which foods contain the most vitamin C?

• Paprika (red): 140mg/100 g
• Acerola cherry
• Lemons
• Oranges
• Broccoli
• Cabbage
• Kiwi
• Grapefruit
• Strawberries
• Cauliflower
• Kohlrabi
• Spinach
• Kale
• Brussels sprouts
• Camu Camu

What are the symptoms of a vitamin C deficiency?

In Europe, people rarely suffer from a serious vitamin C deficiency. However, many people have low vitamin C levels. Older people in particular have an increased need. This is because the body's absorption capacity decreases with increasing age. Smokers should also consume more vitamin C than usual. Cigarette smoke increases the body's exposure to oxidative stress.

These signs indicate a vitamin C deficiency:

• Dry, brittle hair
• Nosebleed
• Slow wound healing
• Bleeding gums
• rough, dry or flaky skin
• Gingivitis (inflammation of the gums)
• Weak immune system (frequent infections)
• Rapid appearance of bruising
• Frequent colds

What is the role of vitamin C?

Vitamin C strengthens the immune system

One of the best-known benefits of vitamin C is its ability to strengthen the immune system. This is why many people increase their vitamin C intake in the fall and winter to protect themselves from colds and/or the flu.

Studies repeatedly confirm the immune-boosting properties of vitamin C. An analysis in the "Annals of Nutrition & Metabolism" showed that sufficient vitamin C can alleviate symptoms of respiratory diseases (e.g. colds) and shorten the duration of the illness. Vitamin C can also reduce the risk of other illnesses such as pneumonia, malaria and diarrhea.

Vitamin C as an effective antioxidant

Antioxidants are compounds that play a central role in our health and in diseases. They fight free radicals that cause disease, minimize oxidative stress and cell damage. Studies show that antioxidants also play a role in the treatment and prevention of various chronic diseases. These include heart disease, autoimmune diseases and even cancer.

Vitamin C acts as an antioxidant in the body and prevents the accumulation of free radicals in the body, protecting it from disease. Some studies give reason to believe that a diet rich in fruit and vegetables (high in vitamin C) can reduce the risk of developing chronic diseases.

Radiant skin thanks to vitamin C

Ascorbic acid or vitamin C is contained in many skin care products and cosmetics. Due to its antioxidant properties, vitamin C strengthens the skin in many ways.

As it is involved in collagen synthesis, studies have shown that the vitamin can halt and reverse skin ageing, protect against skin damage and combat free radicals caused by ultraviolet radiation. In addition, vitamin C can help with skin lightening and hyperpigmentation. Studies show that vitamin C suppresses melanin production and thus prevents dark spots and patches. 

Has a supportive effect in the prevention of anemia

Anemia is the lack of healthy red blood cells. The condition leads to symptoms of anemia such as fatigue, weakness and chest pain. Many factors can cause anemia. Among the most important are deficiencies in the key nutrients vitamin B12 and iron.

Vitamin C can increase iron absorption and thus prevent anemia due to iron deficiency. According to a study in the "American Journal of Clinical Nutrition", taking vitamin C with meals can increase iron absorption by up to 67 percent. It is best to eat iron-rich foods in combination with vitamin C to increase your iron absorption.

Vitamin C improves heart health

A healthy heart is the be-all and end-all for your overall health. It is one of the most important organs in the body and works tirelessly to supply all cells with oxygen and nutrients.

A diet rich in vitamin C can protect the heart from disease. Scientists from the National University of Health Science analyzed 13 studies. The results showed that 500 mg of vitamin C a day could significantly reduce LDL and triglyceride levels. Researchers at the University of Southampton came to similar conclusions. Using a human study, they were able to show that a higher vitamin C intake was associated with a lower risk of premature death due to stroke or coronary heart disease.

UCLA scientists confirm: Vitamin C protects against heart disease

According to Dr. Frei, interest in vitamin C increased when it became known that many degenerative diseases are linked to oxidation. "It was obvious that vitamin C can prevent many of these oxidation processes very effectively because it is a very powerful antioxidant," he explains.

Dr. James Engstrom from UCLA led a large-scale ten-year study. The results also showed that the men who took 800 mg of vitamin C daily developed heart disease less frequently and lived up to six years longer than those who followed the standard recommendation of 60 mg per day.

Another study involving almost 11,200 senior citizens was published in 1996. The researchers observed that seniors who took highly effective vitamin C and vitamin E had an overall reduced mortality rate of 42 percent.

Low-potency multiple vitamin supplements taken only once a day had no positive effect on mortality. Around 40 studies have also shown that people who eat a diet rich in vitamins (with lots of vitamin C) are less likely to develop cancer.

Scurvy is probably the best-known side effect of a pronounced vitamin C deficiency. French researchers also report that people with vitamin C deficiency have an increased risk of fatal hemorrhagic stroke. According to the authors of the study, vitamin C deficiency "should be considered as a risk factor for this severe type of stroke."

They also pointed out that previous studies have concluded that vitamin C can help regulate blood pressure. A higher concentration in the blood can reduce the risk of stroke by more than 40 percent.

A twenty-year prospective cohort study from Japan showed that those with the highest vitamin C concentration in their blood had a 29 percent lower risk of stroke than those with the lowest concentration. In addition, the risk of stroke fell by 54 percent in subjects who ate vegetables six to seven days a week - compared to those who ate vegetables on a maximum of two days.

The common denominator is the effect of vitamin C on our blood vessels. Vitamin C causes the blood vessels to dilate and is necessary for the biosynthesis of collagen. Collagen promotes strong, intact blood vessels. A lack of vitamin C can therefore weaken the blood vessels and lead to scurvy symptoms. These include subcutaneous bleeding (under the skin) and fatal bleeding due to a hemorrhagic stroke.

Vitamin C reduces the risk of developing gout

Gout is a painful arthritic condition associated with swollen and stiff joints. It is caused by the accumulation of uric acid in the joints and most commonly affects the feet and big toe.

Studies show that a higher vitamin C intake can protect against gout. A study published in the "Archives of Internal Medicine" observed almost 47,000 men over a period of 20 years. Those with a higher vitamin C intake had a lower risk of gout than the other subjects. A review study from 2011 came to a similar conclusion. The intake of vitamin C supplements was associated with a significantly lower uric acid level in the blood. This could prevent the onset of gout.

Vitamin C as support in cancer therapy

Just recently, scientists at Lewis Cantley of Weill Cornell Medicine in New York published a research paper. They found that high doses of vitamin C help to kill colon cancer cells with certain genetic mutations and eliminate them from the body. The International Business Times writes:

"More than half of all colorectal cancers in humans are linked to mutations in the KRAS and BRAF genes. The researchers believe that their study results call for more research into the therapeutic use of vitamin C in colorectal cancer."

According to the National Cancer Institute, other studies have shown that high-dose vitamin C can slow the growth of prostate, pancreatic, liver and colon cancer cells. The Institute also recognizes human studies showing that intravenous vitamin C can improve symptoms associated with cancer and cancer treatment, such as fatigue, nausea, vomiting, pain and loss of appetite.

Nevertheless, the US Food and Drug Administration (FDA) has not yet approved intravenous high-dose vitamin C for the treatment of cancer or other diseases.

Vitamin C against cancer cells

Dr. Ronald Hunninghake is an internationally recognized expert on vitamin C who has administered vitamin C intravenously more than 60,000 times.

It all started about 27 years ago when he teamed up with Dr. Hugh Riordan, who was researching intravenous vitamin C for cancer patients. Dr. Riordan discovered that most cancer patients are deficient in vitamin C, especially in the advanced stages of cancer.

Dr. Riordan conducted a 15-year research project called RECNAC (the English word for cancer, "CANCER", spelled backwards). His groundbreaking research in cell cultures showed that vitamin C is selectively cytotoxic against cancer cells. The mechanism for this is summarized in an article by Dr. Hunninghake on orthomolecular.org:

"Cancer cells actively took up vitamin C in a way that led to depletion of C's tissue reserves. PET scans are often ordered by oncologists to screen their patients for metastases (cancer that has spread to other organs).

In preparation for the scans, patients are injected with radioactive glucose. Cancer cells... depend on glucose as their primary fuel source... [and] use transport mechanisms called glucose transporters to actively suck in glucose.

In the vast majority of animals, vitamin C is synthesized from glucose in only four metabolic steps. Therefore, the molecular form of vitamin C is remarkably similar to glucose. Cancer cells actively transport vitamin C into themselves, possibly because they confuse it with glucose. Another plausible explanation is that they use vitamin C as an antioxidant. Regardless of this, vitamin C accumulates in cancer cells.

If large amounts of vitamin C are supplied to the cancer cells, large amounts are also absorbed. In these unusually high concentrations, the antioxidant vitamin C behaves like a pro-oxidant as it reacts with intracellular copper and iron. This chemical interaction produces small amounts of hydrogen peroxide.

Cancer cells contain very little of an intracellular antioxidant enzyme called catalase. The peroxide created by high-dose vitamin C continues to build up and eventually leaches the cancer cell from the inside out! This makes intravenous high-dose vitamin C an effective and non-toxic chemotherapeutic agent that can be administered in conjunction with conventional cancer treatments.

Based on the work of several vitamin C pioneers before him, Dr. Riordan was able to prove that vitamin C is selectively toxic to cancer cells when administered intravenously. This research was recently reproduced and published by Dr. Mark Levine at the National Institutes of Health."

Protect mitochondria with a keto diet

Cancer, neurodegenerative diseases such as Alzheimer's, ALS, Parkinson's and signs of ageing have one thing in common: dysfunctional mitochondria. Dr. Otto Wartburg is considered one of the most brilliant biochemists of the 20th century.

In 1931, he was awarded the Nobel Prize for his research. He discovered that literally every cancer cell does not use oxygen to generate energy, but uses fermented glucose instead.

Interestingly, this use of glucose can contribute to a relative vitamin C deficiency. This is because vitamin C is formed from glucose. This may explain the effectiveness of vitamin C in the treatment of cancer.

Damaged mitochondria benefit most from a ketogenic diet. This usually involves limiting both calorie and carbohydrate intake, particularly all sugars, cereals and most fruits.

Can vitamin C be overdosed?

An overdose of vitamin C is not harmful to a healthy person - and often does not occur in the first place. Too much vitamin C is normally simply excreted by the body, as it is a water-soluble vitamin. However, an overdose of vitamin C can pose risks for people with certain medical conditions.

How much vitamin C should I take?

When taking an oral vitamin C supplement, you should consider the frequency. Steve Hockey, a scientist with a Ph.D. in medical biophysics, explains in his book "Ascorbate" that you can better increase your blood levels of vitamin C if you take vitamin C several times a day. Vitamin C is rapidly excreted via the kidneys. Therefore, you will increase your blood vitamin C level more sustainably if you take vitamin C supplements every one to two hours rather than taking a high dose once a day. (Unless you opt for a sustained-release preparation).

Experiments by the Linus Pauling Institute have shown that the vitamin C concentration in the blood depends on three mechanisms:

• Intestinal absorption
• Tissue transport
• Excretion via the kidneys

A significant increase in the vitamin C concentration in the blood can be achieved with a daily dose of between 30 and 100 mg.

With a daily intake of 200 to 400 mg of vitamin C per day, healthy young adults achieve a stable concentration of 60 to 80 mmol/l. The absorption efficiency could be increased with the intake of 200 mg in one dose.

According to Dr. Andrew Saul, editor of the "Orthomolecular Medicine News Service", 216,000 deaths could be prevented each year if everyone took 500 mg of vitamin C per day. This dose is necessary for a healthy concentration of 80 mmol/l.

Linus Pauling - "The vitamin C man"

One of the most famous proponents of using high doses of vitamin C to treat colds and other illnesses was Linus Carl Pauling (1901-1994). The physical chemist and peace activist was awarded two Nobel Prizes: once for chemistry in 1954 and once with the Nobel Peace Prize in 1962.

The magazine New Scientist lists him as one of the 20 most important scientists of all time. He was almost awarded a third Nobel Prize. But in that case, he was narrowly beaten by Watson and Crick, who discovered the DNA structure.

Despite the fact that he was a highly respected scientist, his views on vitamin C were strongly rejected in medical circles.

He described his discoveries in detail in a series of books: "Vitamin C and the Common Cold" in 1970, "Vitamin C, the Common Cold and the Flu" in 1976, "Vitamin C and Cancer" in 1979 and "How to Feel Better and Live Longer" in 1986.

Many were of the opinion that Pauling's nutritional research was too far outside his specialist field. As a result, he was ignored by conventional medicine and nutritional science for a long time.

Was Pauling right with his view on vitamin C?

The recommended daily dose of vitamin C has been set at 40 to 60 mg per day. According to current recommendations, this amount is more than sufficient to prevent scurvy. However, Pauling advocated doses of 1000 mg and more.

He himself is said to have consumed 12,000 mg of vitamin C per day. Pauling noticed that veterinarians recommended far higher doses of vitamin C for monkeys than for humans.

He therefore initially extrapolated the dose from monkeys and determined a minimum vitamin C requirement of six grams per day - 200 times more than the recommended daily allowance (RDA).

Pauling died of prostate cancer in 1994 at the age of 93. However, interest in vitamin C did not die with him.

Quite the opposite: countless studies have since been carried out to investigate the properties of vitamin C. More recent results indicate that Pauling was not so wrong in his assumptions. In fact, scientific publications from the last two decades since Pauling's death confirm his theories. 

 

Sources (in English):

McRae, M. P. (2008, June). Vitamin C supplementation lowers serum low-density lipoprotein cholesterol and triglycerides: a meta-analysis of 13 randomized controlled trials. Journal of Chiropractic Medicine, 7(2):48-58., doi: 10.1016/j.jcme.2008.01.002

Gale, C. R., Martyn, C. N., Winter, P. D. & Cooper, C. (1995, June). Vitamin C and risk of death from stroke and coronary heart disease in cohort of elderly people. The BMJ, 310(6994): 1563–1566, doi: 10.1136/bmj.310.6994.1563

Pham-Huy, L. A., He, H. & Pham-Huy, C. (2008, June). Free Radicals, Antioxidants in Disease and Health. International Journal of Biomedical Science, 4(2): 89–96

Padayatty, S. J., Katz, A:, Wang, Y., Eck, P., Kwon, O., Lee, J. H. et al. (2003, February). Vitamin C as an antioxidant: evaluation of its role in disease prevention. Journal of the American College of Nutrition, 22(1):18-35, doi: 10.1080/07315724.2003.10719272

Hallberg, L. & Hulthén, L. (2000, May). Prediction of dietary iron absorption: an algorithm for calculating absorption and bioavailability of dietary iron. The American Journal of Clinical Nutrition, 71(5):1147-60, doi: 10.1093/ajcn/71.5.1147

Wintergerst, E. S., Maggini, S. & Hornig, D. H. (2006). Immune-enhancing role of vitamin C and zinc and effect on clinical conditions. Annals of Nutrition & Metabolism, 50(2):85-94, doi: 10.1159/000090495

Al-Niaimi, F. & Chiang, N. Y. (2017, July). Topical Vitamin C and the Skin: Mechanisms of Action and Clinical Applications. The Journal of Clinical and Aesthetic Dermatology, 10(7): 14–17

Choi, H. K., Gao, X. & Curhan, G. (2009, March). Vitamin C Intake and the Risk of Gout in Men – A Prospective Study. Archives of Internal Medicine, 169(5): 502–507, doi: 10.1001/archinternmed.2008.606

Juraschek, S. P., Miller, E. R. & Gelber, A. C. (2011, September). Effect of oral vitamin C supplementation on serum uric acid: a meta-analysis of randomized controlled trials. Arthritis Care & Research, 63(9):1295-306, doi: 10.1002/acr.20519