15 Health Benefits of Vitamin C, According to Science (+15 Best Vitamin C Foods)

Vitamin C, or ascorbic acid, is used to treat a multitude of ailments. Best known for it’s immune system boosting properties, vitamin C is an important component of many cold related medicines. Vitamin C plays a role in combating major diseases to keeping your skin looking youthful and healthy.

Vitamin C is a water soluble vitamin which unlike fat soluble vitamins does not stay in our bodies for a long period of time after consumption. This means that we have to make sure we get the right amount of vitamin C daily through an intake of vitamin C rich foods or supplements.

1. Vitamin C Prevents Scurvy

To those living in the first world scurvy seems like a disease associated with pirates and the distant past, but the truth is that scurvy is still prevalent in the developing world (1).

Scurvy has been a known disease since ancient Egyptian and Greek times (2).

If your body has been deprived of vitamin C for long enough you could develop Scurvy. The disease typically sets in after about three months of being vitamin C deficient.

Some symptoms of scurvy include;

  • Feeling constantly fatigued

  • Swollen and after some time bleeding gums

  • A constant pain in the legs

  • Small blue or red spots on the skin

  • Feeling miserable or irritable for long periods of time

  • Feeling short of breath

  • A prolonged healing period of wounds

  • Swelling and reddish colouration around healed wounds

  • Dry eyes

  • Anemia

  • Mysterious bruises appearing on the skin (3)

If left untreated scurvy can easily turn into jaundice (where the mucous membranes, white of eyes and skin take on a yellowish colour due to high levels of bilirubin building up in the blood) heart problems or oedema (when fluid builds up within the body and causes tissues to swell) (4).

Those most at risk of developing scurvy are people in developing countries, alcoholics, the elderly and children. The only way to treat scurvy is to take oral vitamin C supplements (5).

2. Vitamin C Helps The Skin Maintain Elasticity

Declining collagen levels in the skin cells is a natural side effect of aging. Pollutants in the air and UV damage caused by direct contact with the sun also accelerate the loss of collagen. Vitamin C is essential to the production of elastin and collagen (6).

Eating a cup of certain vitamin C rich foods such as red peppers and oranges provides almost 100 percent of the daily required level of collagen (7). Vitamin C supplements and topical cream are both recommended for maintaining appropriate levels of elastin and collagen which can combat and reduce the development of wrinkles.

A recent study has shown that liposomal vitamin C can leave the skin up to 33 percent firmer (8).

3. Vitamin C Can Effectively Treat The Common Cold

Vitamin C stimulates the defensive actions of our immune systems (9). Molecules that transport vitamin C ared embedded in the membranes of immune cells. These molecules pump vitamin C into the immune cells.

When an infection or inflammation occurs in the body these molecules start to work even harder pumping more and more vitamin C into the cells. Studies show empirical evidence that vitamin C alleviates the symptoms of a cold and that doses administered before or after the cold develops can drastically reduce the period of illness (10).

4. Vitamin C Lowers Hypertension

Hypertension (or high blood pressure) is characterized as having an incredibly high blood pressure as a result of great physiological stress in the body. Symptoms of hypertension include but are not limited to;

  • Blood present in the urine

  • Problems with your vision

  • A pounding sensation in your neck, ears or chest

  • Chest pains

  • An irregular heartbeat

  • Difficulty drawing breath

  • Confusion and or fatigue (11)

Living with hypertension for extended periods of time can result in blood vessels narrowing. It can also result in the formation of blood clots which could cause a stroke or heart failure (12).

A study carried out in over a thousand adults which administered vitamin C supplements to participants with high blood pressure saw a marked drop in both diastolic and systolic (the more serious of the two) blood pressure (13).

The antioxidants in vitamin C protects the supply of nitric acid within the body. Nitric acid is a molecule that works to relax the blood vessels.

5. Vitamin C Cures Cataracts

Cataracts is one of the most common diseases of the eye. The eye has a natural lense which lies behind the pupil and iris. When one develops cataracts this lense becomes cloudy which results in blurred vision. Cataracts accounts for over 50 percent of vision loss in people over the age of 40 and is in fact the leading cause for permanent blindness the world over (14). There are three different types of cataracts that are either associated with aging or diabetes.

Cataracts develops quite slowly and it may take a while to recognise the symptoms. You may start out with slightly blurred vision or lights such as bedside lamps seeming too harsh on the eyes (15).

Causes of cataracts include;

  • Smoking

  • Diabetes

  • Former eye surgeries

  • Hypertension

  • Former eye injuries

  • Alcoholism

A ten year long study in London showed women who regularly took vitamin C supplements and consumed vitamin C rich foods had a 33 percent less chance of developing cataracts (16). The reason for this being that the fluid in the eye is very similar compound wise to vitamin C. The more vitamin C in your system, the more of this fluid and the better protected your eyes are (17).

6. Vitamin C Can Be Used To Treat Lead Toxicity

When you have too much lead in your body you develop lead poisoning as lead is a toxic substance. Symptoms of this illness include constipation, irritability, memory loss, abdominal pains, a tingling in your extremities and infertility (18).

Low levels of vitamin C in the body have been linked to abnormally high levels of lead in the body (18). Studies carried out on animals have shown the doctors were able to completely remove lead from the central nervous system using vitamin C (19).

7. Vitamin C Boosts Your Immune System

High levels of vitamin C have shown a direct link to lessened periods of sickness (flu, cold etc). Vitamin C, or ascorbic acid probably does this by attacking and eliminating the nucleus of viral cells that may compromise our immune system (20). It can also neutralize toxin exposure.

We are all born with an innate immune system and then develop and adaptive system through growing up and being exposed to various bacterias and illnesses. Vitamin C plays an important role in the maintenance of both.

When the immune system detects and pathogens (virus or bacterias) in the body, vitamin C spurs it on to produce interferons (signaling proteins that boost the immune system) (21).

8. Vitamin C Repairs Damaged Tissues

Vitamin C is a vital component in the production of collagen and connective tissue (22). It does this by activating the enzymes crucial to the healing process.

Vitamin C speeds up the healing and repairing of tissues, capillaries, blood vessels and cartilage (23). It is essential for the body to create scar tissues and new skin. Foods high in vitamin C are recommended over vitamin C supplements for tissue repair.

9. Vitamin C Strengthens Bones

Vitamin C is a good for bone health as it increases bone density. Bone mass density is the percentage of bone minerals in the bone tissue (24). When you lose bone density you are at risk for developing bone diseases such as osteoporosis or could result in extremely weakened bones that break very easily.

Interestingly your body is in a constant state of making new bone and reabsorbing old bone. Low bone density occurs when your body reabsorbs too much old bone minerals and tissue and does not make enough new ones (25).

Aging, onset of menopause, loss of testosterone, smoking and alcoholism can also contribute. Studies in mice prove that vitamin C activate osteoblast (bone cells that are still premature) spurring them on to mature quicker into the cells that are needed to maintain bone mass density (26).

10. Vitamin C Maintains Cardiovascular Health

A study was carried out on a group of obese adults showed that getting about 500 milligrams of vitamin C daily could be as helpful to your heart as light exercise (27).

Walking and vitamin C both have a positive effect on endothelin-1, a protein that constricts the blood vessels and could contribute to high blood pressure (28).

Vitamin C also helps the body with vasodilation which is the process by which blood vessels relax or dilate. Vitamin C shown favourable results concerning vasodilation in patients suffering from coronary heart disease (29).

Many obese patients or those suffering from debilitating heart conditions are advised not to exert themselves, so vitamin C is a good way to keep vasodilation under control.

11. Vitamin C Can Prevent The Formation Of Ulcers

Helicobacter pylori is the bacteria responsible for peptic ulcers (sores formed in the small intestine, stomach and on the lower oesophagus) stomach ulcers (as well as contributing to various autoimmune diseases and heart disease). It weakens the lining of stomach leaving it more sensitive to damage from stomach acid (30).

Samples taken over a period of ten years showed a direct relation between high levels of helicobacter pylori and low levels of vitamin C (31). Children more often become infected with helicobacter pylori and the leading cause is through fecal matter in water.

It is recommended to maintain a diet full of vitamin C rich foods to avoid developing ulcers due to this bacteria.

12. Vitamin C Improves Sperm Quality

Spermatogenesis is the process by which healthy sperm is produced. This is a complicated process that requires many hormones and cells to work together and uses a lot of energy and nutrients that you get from the food you eat.

Because of this diet is very important when it comes to sperm production. Your diet can determine the shape and mobility of your sperm. Diets that are higher in dairy and meats tend to have a negative effect on the quantity and quality of sperm produced, whereas vegetables and fruit have a positive effect (32).

A study observing the increase of vitamin C intake on sperm production and health in mice found that higher levels of vitamin C resulted in superior sperm quality and count and far fewer abnormalities in the sperm (33).

13. Vitamin C Reduces The Symptoms Of Asthma

Roughly 1 in 12 people suffer from asthma, a chronic condition where your airways produce extra mucus, swell and constrict causing coughing fits and difficulty breathing.

When you exercise the level of oxidative stress in your body increases. The antioxidative properties of vitamin C acts against it to suppress the negative effects and incidences of a respiratory distress episode taking place (34).

Vitamin C also detoxifies histamine, which is a nitrogenous compound responsible for food or seasonal allergies due to its inflammatory responses. Histamine is an invaluable health tool as it notifies your body quickly when something is wrong and aids in digestion and communication between the brain and body, but can cause discomfort when it is in excess in some people, especially those suffering from asthma (34).

14. Vitamin C Combats Strokes

When you have a stroke the supply of oxygen to your brain is abruptly cut off. When your brain is deprived of oxygen for too long the cells begin to die which can result in severe brain damage or death.

Strokes are either hemorrhagic (bleeding in the brain) or ischemic (caused by a blood clot). Both are potentially deadly, hemorrhagic being more so. Strokes are currently the second highest cause of mortality worldwide.

Studies carried on on 65 hemorrhagic stroke victims have found that over 50 percent have had depleted levels of vitamin C (35). Vitamin C deficiency has now been recognized as a risk factor for strokes.

Vitamin C is known to have tissue strengthening effects and one cause for an uncontained bleed resulting in a hemorrhagic stroke is a breakdown in brain tissue (36).

A Japanese study found vitamin C to be effective in preventing both hemorrhagic and ischemic strokes (37).

15. Vitamin C Fights Cancer

The research is not extensive but does suggest that an incredibly high dose of vitamin C can be

Cytotoxic (harmful) to cancerous cells (38).

Because it is a powerful anti inflammatory, and inflammation is heavily associated with the spread of cancer, vitamin C lowers the pro-inflammatory cytokines that have an impact on the size of tumors.

High dose vitamin C therapy is being recommended as treatment alongside chemotherapy (39).

15 Best Vitamin C Foods

The foods on this list are all loaded with vitamin C and offer all the health benefits associated with it, although it doesn’t stop there.

1. Oranges

Oranges contain a good amount of vitamin A or retinoids. Arguable the most important function of vitamin A is what it does for your eyes. The retinol in vitamin A , or beta carotene, keeps the cornea (the membrane covering our eyes) healthy and can prevent the macular degeneration (the physical breakdown) of the eyes, especially in the elderly.

Vitamin A can also fight night blindness. In Ancient Egypt it was actually noted that the consumption of certain foods such as beef liver (now known to be vitamin A rich) improved night time vision.

Beta carotene also plays a part in acne prevention caused by excess bacteria, sebum or hormones.

Oranges are rich in potassium. Potassium plays a part in ridding the organs of free radicals which in turn prevents urine crystallization and the development of kidney or urinary stones.

2. Guava

Guava is beneficial in lowering cholesterol as it prevents the blood from thickening. When the blood remain fluid it keeps blood pressure down.

Guavas are rich in astringents (a chemical that constricts or shrinks bodily tissues) which have a positive effect on your gums. Astringents also reverse the effects of loose bowels which can reduce periods of diarrhea.

Astringents have antibacterial and disinfectant properties because of its alkaline nature. Because of this it can cure dysentery through removing excess intestinal mucus and the inhibition of microbial growth.

Guava contains copper. Copper is an important component in the regulation of thyroid metabolism. The copper in guavas aids the thyroid gland in regulating certain hormones as well as organ functions.

Vitamin B3, or niacin, and vitamin B6 are also present in guavas. Vitamin B3 increases the blood flow to the brain and has a stimulating effect on cognitive functions and B6 boosts nerve function within the brain.

3. Bell Peppers

You will get more than 200 percent the recommended daily amount of vitamin C from just one bell pepper.

Bell peppers also contain folate, also known as folic acid.

Folate has been linked to the healthy production of sperm. A study carried out in 2012 took a group of infertile men and gave them folate supplements. Once the study was over some of the men had achieved a successful pregnancy with their respective partners. The folate corrects damaged chromosomal structure within the sperm and improves motility.

Folate is also crucial to healthy fetal development. If the mother is deficient of folate in the early stages of pregnancy there is a chance that the foetus will develop defects in the neural tubes. This can lead to a child being born with spina bifida or an increased chance of a miscarriage. The risks of this can actually be reduced by 50 percent if an expected mother takes the recommended dose of daily folate for up to three months after conception.

High folate levels have also been linked to better neurological functions. A study found that elderly patients suffering from dementia had incredibly low folate levels.

4. Strawberries

Strawberries can provide relief for those living with gout or arthritis (a debilitating condition where you experience intense pain and swelling in the joints). Gout occurs when acids and toxic substances build up in the joints, fluid responsible for increasing joint mobility dries up and an excess of free radicals cause the muscles in the joints to start breaking down.

Free radicals also have an accelerating effect on aging because they break down both the brain and nervous system. Another area free radicals can cause massive damage to are the eyes. The breakdown of important tissues in the eye may result in the eyes being more susceptible to a host of infections, the development of dry eye syndrome and vision defects ranging from minor damage to permanent blindness.

Strawberries contain the antioxidants phenolic phytochemicals, ellagic acid and flavonoids. Together they prevent the damage caused by free radicals and correct ocular pressure (the levels of fluid pressure within the eye).

Strawberries are high fiber and vitamin B. They are effective in reducing cholesterol build up in the vessels and arteries. The vitamin B also strengthens the muscles in the heart.

Strawberries contain anthocyanins (a type of flavonoid) which have been found to boost your short term memory if taken for a period longer than eight weeks.

5. Broccoli

Broccoli is a great body detoxifier. This is thanks to the sulphur and vitamin C present in broccoli. It cleanses the body of excess uric acid (high levels can result in developing arthritis and or gout) and cell damaging free radicals. Broccoli actually alkalizes your body, keeping the levels of acid within your body low.

Broccoli also contains a lot of vitamin A or beta carotene, vitamins B and E and omega-3 fatty acids all of which are good for the skin. The glucoraphanin found in broccoli can actually reverse and or reduce the damaging effect the sun has on the skin.

Most stomach disorders all stem from long term constipation. Broccoli is high in roughage and fiber eating enough of it can keep your digestive system moving regularly, preventing potentially more serious bowel problems and diseases.

Kaempferol is a phytonutrient found in broccoli that works against allergy related substances found in the body which reduces the severity of allergic reactions.

Broccoli is high in vitamin K. A vitamin K deficiency could lead to the wearing and break down of bones. It has also been directly related to an increase in risk of bone fractures. One cup of broccoli also yields about 43 milligrams of calcium, another important nutrient needed to keep your bones healthy and protected. Vitamin K and calcium are necessary in preventing the development of osteoporosis.

The omega-3 fatty acids in broccoli can also work as a protector against, or at least delay the onset of, Lou Gehrig's disease (a motor neuron disease also known as ALS).

6. Brussel Sprouts

Brussels sprouts can give you more than 270 percent of your recommended daily intake of vitamin K. This makes it a strong player in the world of organic bone health aids. Vitamin K also plays an important role in preventing bone calcification (when calcium salts build up in the soft tissues in and surrounding the bones).

Brussel sprouts contain glucosinolates, a natural compound which strengthens the lining of the stomach and digestive tract. This can lessen the odds of developing what is known as leaky gut syndrome (a disease that increases inflammation in the stomach and intestines).

7. Papaya

Papaya roots can be made into a paste that provides relief from toothaches. The bark of the papaya tree can also be used.

Papaya contains an enzyme called papain. Papain regulates menstruation and can help to ease severe menstrual pains. Papain is also good for the skin. Papaya is used in face masks as the papain kills off dead cells in the skin.

The vitamins E,A and C in papayas make them a useful tool in combating diabetic heart disease and atherosclerosis (the calcification and thickening of the artery walls in your heart due to a build up of white blood cells).

A form of latex is made from papaya that is used to treat burns and acne scarring.

The vitamin A found in papaya boosts the production of sebum which keeps your hair strong and healthy and promotes growth. Applying papaya extract to your scalp can also combat dandruff.

If you are pregnant it is best to avoid raw papaya.

8. Tomato

Nitrosamines are a carcinogenic (a substance or agent that relates directly to the development of cancer) are found in cigarettes and are naturally produced within the body. Tomatoes contain chlorogenic acid and coumaric acid. Both of these work against the damaging and cancer causing effects of too much nitrosamines.

Tomatoes are rich in potassium. Potassium is what is known as a vasodilator (something that lowers the pressure in the arteries and blood vessels). This action eliminates hypertension and boosts circulation which in turn decreases any stress that may be on the heart.

The vitamin K and calcium in tomatoes helps to heal damaged bones and bone tissues and naturally carrying out minor repairs in these areas.

Studies have shown that including the seeds of tomatoes in your diet may be beneficial in preventing the formation of kidney or urinary stones. Tomatoes are also diuretic (anything that boosts the production of urine) because it holds so much water. This reduces the chance of incidences of bladder cancer and the development of urinary tract infections.

Chromium is a mineral found in tomatoes. Chromium is key to keeping blood sugar levels under control which is good for diabetics. Studies have also found that consuming tomatoes daily can reduce oxidative stress (the difference between the production of free radicals and the ability of the body to neutralize the harmful effects or the detoxification of the free radicals).

When applied topically, tomatoes can treat severe sunburns. Eating enough tomatoes can protect your skin against UV induced erythema (when blood vessels dilate or you sustain an injury causing red patches on the skin).

9. Kale

Kale is possibly the most nutrient dense vegetable available. It contains vitamins A, C, K and B (1,2,3 and 6) as well as manganese, magnesium, calcium, copper and potassium, to name a few!

Kale contains nearly no fats but the fat it does hold is omega-3 fatty acids which is the most beneficial fat.

Kale is chock full of antioxidants, polyphenols and flavonoids (including kaempferol and quercetin). Numerous animal studies have found that these substances can lower blood pressure, have anti-cancer, anti-depression, anti-inflammatory and antiviral properties and have powerful cardioprotective effects.

The high levels of folate in kale is great for pregnant women and the healthy development of the fetus. Folate ensures that the heart and face develop correctly and that baby is born at a healthy weight.

It is important for pregnant women to make sure that they are getting real folate and not relying completely on folate supplements as these supplements have been linked to some negative side effects including epilepsy, drop in libido, epilepsy, loss of sleep and emotional changes.

That dark green colour of kale is because of the nutrients zeaxanthin and lutein. These nutrients prevent macular degeneration (an incurable disease of the eye that affects more than 10 million people in the USA every year) in the eyes. These nutrients behave as antioxidants within the eye and keep the cells in the eyes healthy and safe from the damage of free radicals.

Kale has one of the highest levels of vitamin K than almost any other food. Vitamin K is crucial when it comes to blood clotting. Vitamin K promotes coagulation in the blood when necessary (if you’ve been injured and the body needs to produce a sab to stop the bleeding). It does this by waking up certain proteins and spurring them on to begin binding calcium in the blood.

Kale contains more calcium than even milk and is able to prevent or lessen the effects of osteoporosis.

10. Pineapple

Pineapples are good for those suffering from arthritis. Pineapples contain bromelain, a proteolytic enzyme that in quite rare. The main function of bromelain is breaking down complex proteins but but it also has some very impressive anti-inflammatory properties. Studies have confirmed that bromelain reduces the severe inflammation in the joints and thus alleviates many of the painful symptoms and signs associated with arthritis.

Bromelain also reduces mucus and phlegm that collect in the sinus cavities and respiratory tracts. It also helps to dislodge andy phlegm or mucus that is already there. The bromelain and vitamin C present make pineapples a powerful tool in combatting colds and other illnesses.

Pineapples are a good source of both insoluble and soluble fiber. The fiber bulks up stool which can prevent diarrhea and the prevention of irritable bowel syndrome. Fiber is also responsible for triggering the release of digestive and gastric juices which help to dissolve foods in the stomach. Getting enough fiber also ensures that your blood vessels are stripped clean of excess cholesterol, preventing buildups and potential clots, strokes and heart disease.

Pineapple can strengthen your gums through their astringent properties. When your gums are weak you are at high risk for contracting painful gum diseases, gum retraction and tooth loss. Astringents tone and tighten tissues within the body which in turn prevent hair and tooth loss and the loosening of skin.

11. Kohlrabi

Kohlrabi is a kind of turnip cabbage that can be consumed raw or cooked. It has been eaten in many Germanic countries for hundreds of years. You can eat the actual bulb and the leaves.

Kohlrabi contains high amounts of potassium. Potassium is actually quite a key player in ensuring that our nerve and muscle behaviour remain normal. The functions of moving, reacting and even breathing are aided by potassium.

Kohlrabi contains a variety of B vitamins. These vitamins each play a key role in enzymatic process (enzymes speed up or kick start chemical reactions as well as converting molecules into different molecules needed for certain functions) within the body.

Kohlrabi contains minimal fat and absolutely no cholesterol.

The leaves of kohlrabi are full of vitamins A, B, k and carotenoids.

12. Mango

The large amount of fiber found in mangoes can prevent the onset of various bowel related diseases such as constipation, piles and spastic colon (another term for irritable bowel syndrome).

Mangoes are incredibly low in sodium, cholesterol and saturated fat. They are a popular home remedy in China for various ailments including bleeding gums, constipation and anemia (when the body is hemoglobin or red blood cell deficient).

Mangoes are sometimes referred to as an anti-aging food as the high levels of vitamins A and C raise the level of collagen proteins in the skin cells. It also unclogs pores on the face which prevents the development of blackheads and acne. Mangoes can also be used to make a body scrub for external skin application.

Mangoes can be used to provide a boost in the libido. The vitamin E present in the fruit can regulate the hormones responsible for your sex drive and can raise your sex drive.

If your body overheats it could result in what is known as heat stroke. Heat stroke is a very serious condition triggered by incredibly high heats in which the body's ability to self regulate is shut down. Symptoms of heat stroke are;

  • Confusion

  • Having difficulty breathing

  • A rising body temperature

  • A rapid pulse

Heat stroke is considered to be a medical emergency and if one does not receive help it can lead to organ damage and can be fatal. The pulp of boiled mangoes is a popular home remedy for heat stroke.

13. Peas

One cup of peas yield up to 10 grams of an organic compound called coumestrol. Studies have shown that just 2 grams a day can combat stomach cancer.

Peas have certain inflammatory phytonutrients that are not found in any other foods. These phytonutrients These phytonutrients and the omega-3 fatty acids found in peas can prevent or slow down the development of wrinkles, bronchitis, candida (a kind of fungus that grows inside the body) and alzheimer's.

Peas are good for blood sugar regulation as the fiber makes sure that sugars are released slowly and the anti inflammatories and antioxidants in peas can reverse or prevent insulin resistance.

Peas contain niacin which causes the body to produce less triglycerides which decreases the amount of harmful cholesterols in the body.

Peas are not only good for our bodies but good for the soil they grow in too as they act as a great organic fertilizer.

14. Blackcurrant

Blackcurrants are very low on the glycemic index. The natural sugars in blackcurrant is slowly absorbed into your blood stream meaning that there is no sugar spike and crash.

Blackcurrants are incredibly rich in manganese. Manganese is an important component in the production of enzymes pivotal to energy production.

The high levels of magnesium in blackcurrants helps to regulate your sleep cycle and provide undisturbed rest, The way in which blackcurrants regulate the metabolism also has a positive effect on the quality and duration of sleep.

Your kidneys filter blood removing all harmful waste from the blood stream. When you develop kidney stones it can hinder the kidney's capacity to do their job. Blackcurrants reduce the likelihood of the formation of kidney stones.

Blackcurrants contain both copper and iron which are needed for the body to produce new red blood cells.

15. Kiwi

Kiwis contain the protein-dissolving enzyme called actinidin. Actinidin aids in the digestion of food.

The potassium in kiwis are good for your blood pressure as it keeps our electrolytes balanced because of how it counteracts the harmful effects of too much sodium.

The vitamin C present in kiwis can have alleviating effects on the symptoms respiratory diseases such as wheezing, sore throat and head congestion. Studies have shown that kiwis are able to provide relief for both children and adults suffering from asthma.

The particular antioxidants found in kiwis can actually protect DNA from damage caused by oxidation.

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