Table of Contents

Vitamin A and C: Absorption, Benefits, and Dosage

Takeaways

  • Vitamins A and C work together to boost immunity and skin health
  • Both vitamins have antioxidant properties that protect cells
  • Proper absorption of these vitamins depends on various factors
  • Balanced intake through diet is preferable to supplements for most people
  • Deficiency in either vitamin can lead to serious health issues
  • Excessive intake, especially of vitamin A, can be harmful

Dynamic Duo: Vitamin A and C

Vitamins A and C are crucial for maintaining good health. These nutrients collaborate to support various bodily functions and processes that keep us healthy.[1]

Vitamin A is important for vision, skin health, and a strong immune system. Vitamin C strengthens the immune system, acts as an antioxidant, and helps the body absorb iron more efficiently.[2]

Vitamins A and C are frequently discussed together because they work well with each other. When combined, their effects can be more significant than if they were taken separately.[3]

Vitamin A: The Vision Vitamin

Forms and Sources

Vitamin A exists in two primary forms: retinoids and carotenoids. Retinoids are found in animal-based foods, while carotenoids are present in plant-based foods.[4]

Retinoids are a ready-to-use form of vitamin A that the body can utilize immediately. They are found in foods like liver, eggs, and dairy.[5] Carotenoids need to be converted into vitamin A by the body, and they’re abundant in foods such as carrots, sweet potatoes, and spinach.[6]

Here are some common foods that contain high amounts of vitamin A:

  • Beef liver
  • Sweet potato
  • Spinach
  • Carrots
  • Mango
  • Eggs
  • Milk

Functions in the Body

Vitamin A is essential for healthy vision, as it plays a key role in forming and maintaining the eyes. This vitamin is part of rhodopsin, a protein in the eyes that helps us see in low-light situations.[7]

Vitamin A is also needed for a healthy immune system. It helps produce and control immune cells that defend the body from harmful substances. Additionally, it supports the health of surface tissues, which act as barriers against infections.[8]

Skin health and cell growth rely on vitamin A. It assists in creating and repairing skin cells and also helps the body produce collagen and elastin, which strengthen the skin.[9]

Vitamin C: The Immune Booster

Chemical Structure and Properties

Vitamin C, also known as ascorbic acid, has a simple molecular structure composed of carbon, hydrogen, and oxygen. This structure provides vitamin C with its unique characteristics.[10]

One of vitamin C’s main functions is to act as an antioxidant. It protects cells from damage caused by unstable molecules called free radicals. By neutralizing these molecules, vitamin C keeps our cells healthy.[11]

Here’s a comparison of the vitamin C levels found in various foods:

Food (100g serving) Vitamin C Content (mg)
Red Bell Pepper 190
Kiwifruit 93
Broccoli 89
Strawberries 59
Orange 53

Natural Sources

Many foods, especially fruits and vegetables, are sources of vitamin C. Citrus fruits like oranges and lemons are well-known, but some foods contain even higher amounts of this vitamin.[12]

The amount of vitamin C in food can vary based on factors such as storage and cooking methods. Generally, fresh, raw foods contain the most vitamin C, while cooking can decrease the vitamin’s content.[13]

The best food sources for vitamin C include:

  • Bell peppers
  • Kiwifruit
  • Strawberries
  • Broccoli
  • Brussels sprouts
  • Oranges
  • Potatoes

Synergy Between Vitamins A and C

Vitamins A and C work together in the body to support and enhance each other’s functions, resulting in a more effective outcome than when they act alone.[14]

The immune system benefits significantly from the combined action of these two vitamins. Vitamin A helps create white blood cells, and vitamin C protects them from damage, resulting in a stronger defense against illnesses.[15]

Skin health is improved by both vitamins working in tandem. Vitamin A encourages skin cell growth, while vitamin C helps produce collagen, keeping skin firm and healthy.[16]

Here’s an explanation of how vitamins A and C work together in various body systems:

Body System Vitamin A Role Vitamin C Role Combined Effect
Immune Creates immune cells Protects immune cells Stronger immunity
Skin Promotes cell growth Builds collagen Healthier skin
Eyes Forms eye tissues Protects eye tissues Better vision
Bones Supports bone growth Aids collagen formation Stronger bones

Absorption and Metabolism

Vitamin A Absorption

Vitamin A is absorbed in the small intestine. The process begins with the vitamin mixing with bile acids, forming small droplets that are easier for the body to take in.[17]

Several factors can affect how well vitamin A is absorbed. The presence of fat in the diet is one factor, as vitamin A is fat-soluble. Overall health and age also influence absorption.[18]

Vitamin C Absorption

Vitamin C is also absorbed in the small intestine. The body uses specific transporters to move vitamin C into the bloodstream. While efficient, this process has its limits.[19]

The amount of vitamin C consumed affects how much is absorbed. Lower doses are typically absorbed more efficiently, while higher doses see a decrease in absorption percentage. Other nutrients, such as alcohol, can also reduce absorption.[20]

These are the steps involved in the absorption and metabolism of vitamin C:

  1. Ingestion of vitamin C through food or supplements
  2. Breakdown of food in the stomach
  3. Absorption in the small intestine
  4. Transport into the bloodstream
  5. Distribution to body tissues
  6. Use by cells for various functions
  7. Excess vitamin C filtered by kidneys and excreted

Health Benefits of Combined Intake

Immune System Support

Vitamins A and C combine their efforts to strengthen the immune system by helping to create and maintain immune cells and support their function.[21]

Vitamin A supports the development of white blood cells, which defend against infections. Vitamin C protects these cells from harm and helps them function more effectively.[22]

The combination of these vitamins can improve the body’s immune response, which may help in fighting off illnesses. Some research suggests it might even shorten the duration of common colds.[23]

Skin Health

Skin health significantly benefits from vitamins A and C. They work together to maintain healthy and youthful-looking skin, achieving results that surpass what each vitamin can do alone.[24]

Vitamin A encourages the growth of new skin cells, repairs damaged skin, and regulates oil production. Vitamin C is essential for producing collagen, which keeps the skin firm and elastic.[25]

Together, these vitamins can improve skin texture and appearance. They may help reduce the appearance of fine lines and wrinkles, and research indicates they might even offer some protection against sun damage.[26]

Eye Health

Vitamins A and C play vital roles in maintaining eye health. They support various aspects of vision and eye function, and their combined effects can help preserve good eyesight as we get older.[27]

Vitamin A is crucial for good vision, especially in low light, as it’s a component of rhodopsin. Vitamin C supports healthy blood vessels in the eye.[28]

These vitamins might help prevent age-related eye diseases. Studies suggest they could reduce the risk of cataracts and macular degeneration, though more research is needed for confirmation.[29]

Recommended Dosage

Vitamin A Daily Intake

The recommended daily intake of vitamin A varies depending on age and gender. Adults typically need between 700 and 900 micrograms (mcg) per day. Pregnant women need slightly more, around 770 mcg daily.[30]

It’s crucial not to consume excessive amounts of vitamin A. The upper limit for adults is 3,000 mcg per day. Overconsumption, particularly through supplements, can lead to toxicity. This risk is higher with retinol, the animal-based form of vitamin A.[31]

Vitamin C Daily Intake

The recommended daily intake for vitamin C is higher than for vitamin A. Adult men should aim for 90 milligrams (mg) daily, while women need about 75 mg daily. Smokers require an additional 35 mg per day.[32]

Unlike vitamin A, vitamin C is water-soluble, meaning that excess amounts are usually excreted in urine. However, very high doses can cause digestive issues. The upper limit for adults is 2,000 mg per day.[33]

Individual vitamin needs can fluctuate based on lifestyle factors. People under stress or those who exercise intensely might require a higher intake. Always consult a doctor before making significant changes to your vitamin intake.[34]

Deficiency and Excess

Vitamin A Deficiency

Vitamin A deficiency can lead to various health issues, with vision problems being the most common. Night blindness is an early sign of deficiency, and severe cases can lead to complete blindness.[35]

Other symptoms of vitamin A deficiency include:

  • Dry, rough skin
  • Delayed growth in children
  • Weakened immune system
  • Increased risk of infections

Certain groups have a higher risk of vitamin A deficiency, including pregnant women, breastfeeding mothers, young children, and individuals with malabsorption disorders.[36]

Vitamin C Deficiency

Severe vitamin C deficiency leads to scurvy, a condition once common among sailors. While rare in developed countries today, mild deficiency can still occur.[37]

Symptoms of vitamin C deficiency include:

  • Fatigue and weakness
  • Joint pain
  • Easily bruising
  • Slow wound healing
  • Dry, splitting hair

The risk of vitamin C deficiency in modern times is higher for certain groups, including smokers, those with limited food choices, and individuals with certain medical conditions.[38]

Excess Intake Concerns

While consuming enough vitamins A and C is essential, consuming too much can be harmful, particularly with vitamin A, as excess intake can cause toxicity, especially from supplements.[39]

Symptoms of vitamin A toxicity include:

  • Nausea and vomiting
  • Headache
  • Blurred vision
  • Skin irritation
  • In severe cases, liver damage

Excess vitamin C is less of a concern because the body usually eliminates it through urine. However, very high doses can cause digestive issues like diarrhea and nausea.[40]

It’s best to obtain vitamins from a balanced diet. If you’re considering supplements, consult a healthcare provider first to determine if they are needed and what dosage is safe.[41]

Supplementation Considerations

Sometimes, dietary intake alone might not provide enough vitamins A and C, making supplementation necessary. However, supplementation should be approached cautiously.[42]

Supplements can be beneficial for people with certain health conditions, such as those with malabsorption issues or restricted diets. Pregnant women and older adults may also benefit from supplements.[43]

When choosing supplements, consider the form and quality. Vitamin A supplements come as retinol or beta-carotene, while vitamin C supplements are typically ascorbic acid. Choose reputable brands and check for third-party testing.[44]

Here are some of the common types of vitamin A and C supplements:

  • Vitamin A:

    • Retinol (preformed vitamin A)
    • Beta-carotene (provitamin A)
    • Multivitamins containing vitamin A
  • Vitamin C:

    • Ascorbic acid tablets
    • Chewable vitamin C
    • Liquid vitamin C
    • Multivitamins containing vitamin C

With supplements, remember that more isn’t always better. It’s important to stick to the recommended dosages unless a healthcare provider advises otherwise.[45]

Interactions with Other Nutrients

Vitamins A and C don’t work in isolation; they interact with other nutrients in the body, which can either improve or reduce their effectiveness.[46]

Vitamin A works with vitamin D to support bone health and immune function, while vitamin E complements vitamin A’s antioxidant effects. However, too much vitamin A can interfere with vitamin D absorption.[47]

Vitamin C enhances iron absorption, particularly from plant sources, and works with vitamin E to protect cells from damage. High doses of vitamin C, however, might interfere with copper absorption.[48]

Here’s a table illustrating some of the interactions between vitamins A, C, and other nutrients:

Nutrient Pair Interaction
Vitamin A + D Support bone health and immunity
Vitamin A + E Enhanced antioxidant effects
Vitamin C + Iron Improved iron absorption
Vitamin C + E Better cell protection
Vitamin A + Zinc Supports night vision
Vitamin C + Copper High vitamin C may reduce copper absorption

Understanding these interactions can help in making informed dietary decisions and highlights the importance of a balanced diet over isolated supplements.[49]

FAQ: Common Questions About Vitamins A and C

People often have questions about vitamins A and C. Here are some common questions and answers:

Can taking vitamin C prevent colds?
Vitamin C may not prevent colds, but it might reduce their duration. Some studies show it can shorten colds by about one day.[50]

Is it possible to get too much vitamin A from food?
It’s rare to get too much vitamin A from food alone. However, eating large amounts of liver regularly could lead to excess intake.[51]

How does cooking affect vitamin C content in foods?
Cooking can reduce vitamin C content in foods. Steaming or microwaving vegetables can help retain more vitamin C compared to boiling.[52]

Can vitamin A improve night vision?
Vitamin A is essential for good vision, especially in low light. However, taking extra won’t improve vision if you’re not deficient.[53]

Is it better to take vitamins A and C together or separately?
These vitamins work well together and can be taken at the same time. However, it’s best to get them from a balanced diet when possible.[54]

Do smokers need more vitamin C?
Yes, smokers need about 35 mg more vitamin C per day than non-smokers. Smoking increases oxidative stress, which vitamin C helps combat.[55]

Conclusion

Vitamins A and C are potent nutrients with wide-ranging benefits for health. They boost immunity and promote skin health, and their combined effects can be even more powerful.[56]

Although supplements can be useful, it’s often best to get these vitamins from food. A diet rich in fruits, vegetables, and some animal products can provide ample amounts, along with other beneficial nutrients found in whole foods.[57]

Maintaining balance is key when it comes to vitamins A and C. Insufficient intake can lead to deficiencies, while excessive intake can cause problems. Consult with a healthcare provider if you have concerns about your vitamin intake. They can offer advice tailored to your health needs.[58]

By understanding these vitamins and making informed choices, we can maximize their benefits for better health. Whether through diet or supplements, vitamins A and C can support our overall wellbeing in many ways.[59]

Fact Check
Claim: Vitamins A and C are crucial for maintaining good health. These nutrients collaborate to support various bodily functions and processes that keep us healthy.
Fact check: True. Both vitamins are essential for health and work together.

Vitamin A supports vision, immune function, and skin health, while vitamin C acts as an antioxidant and supports immune function. Their combined action enhances overall health.

Claim: Vitamin A is important for vision, skin health, and a strong immune system. Vitamin C strengthens the immune system, acts as an antioxidant, and helps the body absorb iron more efficiently.
Fact check: True. These are established functions of each vitamin.

These are widely recognized roles of vitamins A and C. Vitamin A deficiency can lead to vision issues, skin problems, and impaired immunity, and vitamin C is critical for collagen synthesis and iron absorption.

Claim: Vitamins A and C are frequently discussed together because they work well with each other. When combined, their effects can be more significant than if they were taken separately.
Fact check: True. They have synergistic effects in the body.

Their combined action is more effective than their individual contributions, particularly in immune function and skin health.

Claim: Vitamin A exists in two primary forms: retinoids and carotenoids. Retinoids are found in animal-based foods, while carotenoids are present in plant-based foods.
Fact check: True. These are the two main forms of vitamin A.

Retinoids are preformed vitamin A, while carotenoids (like beta-carotene) are provitamin A that the body converts.

Claim: Retinoids are a ready-to-use form of vitamin A that the body can utilize immediately. They are found in foods like liver, eggs, and dairy.
Fact check: True. Retinoids are directly usable by the body.

These sources are good providers of retinol which is a preformed vitamin A

Claim: Carotenoids need to be converted into vitamin A by the body, and they’re abundant in foods such as carrots, sweet potatoes, and spinach.
Fact check: True. Carotenoids are precursors to vitamin A.

The body converts beta-carotene (a type of carotenoid) into vitamin A. These foods are great sources of this provitamin.

Claim: Vitamin A is essential for healthy vision, as it plays a key role in forming and maintaining the eyes. This vitamin is part of rhodopsin, a protein in the eyes that helps us see in low-light situations.
Fact check: True. Vitamin A is crucial for vision.

Vitamin A deficiency causes night blindness, and is a known component of rhodopsin

Source: “Fortification of staple foods with vitamin A for vitamin A deficiency” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6509778/

Claim: Vitamin A is also needed for a healthy immune system. It helps produce and control immune cells that defend the body from harmful substances. Additionally, it supports the health of surface tissues, which act as barriers against infections.
Fact check: True. Vitamin A supports immunity and tissue health.

Vitamin A supports immune cell development and function, as well as the integrity of mucosal barriers against pathogens.

Source: “New Insight on the Immune Modulation and Physical Barrier Protection Caused by Vitamin A in Fish Gills Infected With Flavobacterium columnare” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8992971/

Claim: Skin health and cell growth rely on vitamin A. It assists in creating and repairing skin cells and also helps the body produce collagen and elastin, which strengthen the skin.
Fact check: True. Vitamin A is important for skin health.

Vitamin A is involved in cell proliferation, differentiation, and extracellular matrix production, including collagen and elastin

Claim: Vitamin C, also known as ascorbic acid, has a simple molecular structure composed of carbon, hydrogen, and oxygen. This structure provides vitamin C with its unique characteristics.
Fact check: True. The molecular formula is C6H8O6

Ascorbic acid’s structure gives it antioxidant and reducing properties, contributing to its role in various bodily functions.

Claim: One of vitamin C’s main functions is to act as an antioxidant. It protects cells from damage caused by unstable molecules called free radicals. By neutralizing these molecules, vitamin C keeps our cells healthy.
Fact check: True. Vitamin C is a potent antioxidant.

Vitamin C donates electrons to neutralize free radicals, helping prevent oxidative damage.

Claim: Many foods, especially fruits and vegetables, are sources of vitamin C. Citrus fruits like oranges and lemons are well-known, but some foods contain even higher amounts of this vitamin.
Fact check: True. Many foods are sources of vitamin C.

Other foods rich in vitamin C include bell peppers, kiwi, strawberries, and broccoli.

Claim: The amount of vitamin C in food can vary based on factors such as storage and cooking methods. Generally, fresh, raw foods contain the most vitamin C, while cooking can decrease the vitamin’s content.
Fact check: True. Vitamin C is heat-sensitive and can degrade during cooking and storage.

Vitamin C is water-soluble and can leach out into cooking water. Oxidation during storage also reduces levels.

Claim: Vitamins A and C work together in the body to support and enhance each other’s functions, resulting in a more effective outcome than when they act alone.
Fact check: True. They have synergistic effects.

Their combined action, is more potent than the effects when functioning alone.

Claim: The immune system benefits significantly from the combined action of these two vitamins. Vitamin A helps create white blood cells, and vitamin C protects them from damage, resulting in a stronger defense against illnesses.
Fact check: True. They enhance immune function through complementary mechanisms.

Vitamin A is crucial in white blood cell development, and vitamin C helps them function effectively by protecting them from oxidative damage.

Claim: Skin health is improved by both vitamins working in tandem. Vitamin A encourages skin cell growth, while vitamin C helps produce collagen, keeping skin firm and healthy.
Fact check: True. They both contribute to skin health, with different roles.

Vitamin A supports cell proliferation and repair. Vitamin C is critical for collagen synthesis.

Claim: Vitamin A is absorbed in the small intestine. The process begins with the vitamin mixing with bile acids, forming small droplets that are easier for the body to take in.
Fact check: True. Fat-soluble vitamins are absorbed in this way.

Vitamin A, being fat-soluble, requires bile for emulsification and absorption.

Claim: Several factors can affect how well vitamin A is absorbed. The presence of fat in the diet is one factor, as vitamin A is fat-soluble. Overall health and age also influence absorption.
Fact check: True. Absorption is affected by various factors.

Fat intake enhances absorption of fat-soluble vitamins. Age and health conditions affecting digestion can also impact absorption.

Claim: Vitamin C is also absorbed in the small intestine. The body uses specific transporters to move vitamin C into the bloodstream. While efficient, this process has its limits.
Fact check: True. This is the mechanism of vitamin C uptake.

Sodium-dependent vitamin C transporters (SVCTs) are involved in the absorption of vitamin C

Claim: The amount of vitamin C consumed affects how much is absorbed. Lower doses are typically absorbed more efficiently, while higher doses see a decrease in absorption percentage. Other nutrients, such as alcohol, can also reduce absorption.
Fact check: True. Vitamin C absorption efficiency decreases at higher dosages.

Absorption efficiency decreases because the transporters saturate at higher concentrations. Alcohol can interfere with nutrient absorption.

Claim: Vitamins A and C combine their efforts to strengthen the immune system by helping to create and maintain immune cells and support their function.
Fact check: True. They support immune function.

Vitamin A supports immune cell production and vitamin C maintains their function and protects from damage

Claim: Vitamin A supports the development of white blood cells, which defend against infections. Vitamin C protects these cells from harm and helps them function more effectively.
Fact check: True. Both have roles in immune cell function.

Vitamin A is important for cellular differentiation and vitamin C has antioxidant and immune-supportive properties

Claim: The combination of these vitamins can improve the body’s immune response, which may help in fighting off illnesses. Some research suggests it might even shorten the duration of common colds.
Fact check: Potentially true. Immune function may be enhanced, although cold duration reduction is modest

There is some evidence that Vitamin C may reduce the duration of a cold. Vitamin A helps the immune system maintain its functions

Claim: Skin health significantly benefits from vitamins A and C. They work together to maintain healthy and youthful-looking skin, achieving results that surpass what each vitamin can do alone.
Fact check: True. They provide complimentary benefits to skin health.

Vitamin A is for cell production and repair. Vitamin C is for collagen formation and antioxidant activity

Claim: Vitamin A encourages the growth of new skin cells, repairs damaged skin, and regulates oil production. Vitamin C is essential for producing collagen, which keeps the skin firm and elastic.
Fact check: True. These are the individual roles of the vitamins.

Vitamin A is important for differentiation and Vitamin C is essential for collagen synthesis.

Claim: Together, these vitamins can improve skin texture and appearance. They may help reduce the appearance of fine lines and wrinkles, and research indicates they might even offer some protection against sun damage.
Fact check: Potentially true. Some evidence supports these benefits, but further research is needed.

Antioxidant protection against sun damage has been shown. Fine line and wrinkle reduction has been observed, particularly with retinol.

Claim: Vitamins A and C play vital roles in maintaining eye health. They support various aspects of vision and eye function, and their combined effects can help preserve good eyesight as we get older.
Fact check: True. Both play a role in eye health.

Vitamin A deficiency can lead to night blindness and other vision problems. Vitamin C’s antioxidant properties may protect against age related damage.

Claim: Vitamin A is crucial for good vision, especially in low light, as it’s a component of rhodopsin. Vitamin C supports healthy blood vessels in the eye.
Fact check: True. They have specific roles in vision.

Vitamin A is essential for rhodopsin formation, and vitamin C may maintain the health of ocular blood vessels.

Claim: These vitamins might help prevent age-related eye diseases. Studies suggest they could reduce the risk of cataracts and macular degeneration, though more research is needed for confirmation.
Fact check: Potentially True. There is some evidence of this effect but more research is needed

Antioxidant properties of vitamins C and A are theorized to help prevent eye disease. However, more research is needed to confirm cause and effect.

Claim: The recommended daily intake of vitamin A varies depending on age and gender. Adults typically need between 700 and 900 micrograms (mcg) per day. Pregnant women need slightly more, around 770 mcg daily.
Fact check: True. These are generally accepted guidelines.

These numbers represent the recommended dietary allowances (RDA) for vitamin A intake, but vary based on age, sex, and health conditions.

Source: “Effects of primary or secondary prevention with vitamin A supplementation on clinically important outcomes: a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11141198/

Claim: It’s crucial not to consume excessive amounts of vitamin A. The upper limit for adults is 3,000 mcg per day. Overconsumption, particularly through supplements, can lead to toxicity. This risk is higher with retinol, the animal-based form of vitamin A.
Fact check: True. Vitamin A toxicity is a concern with over-supplementation.

Retinol, due to its preformed nature, is more likely to cause toxicity. The UL is important to adhere to.

Source: “Vitamin A Update: Forms, Sources, Kinetics, Detection, Function, Deficiency, Therapeutic Use and Toxicity” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8157347/

Claim: The recommended daily intake for vitamin C is higher than for vitamin A. Adult men should aim for 90 milligrams (mg) daily, while women need about 75 mg daily. Smokers require an additional 35 mg per day.
Fact check: True. These are the general recommendations.

These are the recommended dietary allowances (RDA) for vitamin C for adults. Smokers require more due to increased oxidative stress.

Source: “SVCT2–mediated ascorbic acid uptake buffers stress responses via DNA hydroxymethylation reprogramming of S100 calcium-binding protein A4 gene” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9694147/

Claim: Unlike vitamin A, vitamin C is water-soluble, meaning that excess amounts are usually excreted in urine. However, very high doses can cause digestive issues. The upper limit for adults is 2,000 mg per day.
Fact check: True. Excess vitamin C is excreted.

Water-soluble vitamins are not stored in the body. Very high doses, can cause GI problems.

Source: “SVCT2–mediated ascorbic acid uptake buffers stress responses via DNA hydroxymethylation reprogramming of S100 calcium-binding protein A4 gene” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9694147/

Claim: Individual vitamin needs can fluctuate based on lifestyle factors. People under stress or those who exercise intensely might require a higher intake. Always consult a doctor before making significant changes to your vitamin intake.
Fact check: True. Needs can vary based on lifestyle.

People with increased metabolic demands or who are under stress may have higher nutrient needs.

Claim: Vitamin A deficiency can lead to various health issues, with vision problems being the most common. Night blindness is an early sign of deficiency, and severe cases can lead to complete blindness.
Fact check: True. Vitamin A deficiency commonly leads to vision problems.

Severe vitamin A deficiency can lead to xeropthalmia which causes permanent blindness.

Source: “Fortification of staple foods with vitamin A for vitamin A deficiency” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6509778/

Claim: Certain groups have a higher risk of vitamin A deficiency, including pregnant women, breastfeeding mothers, young children, and individuals with malabsorption disorders.
Fact check: True. These groups are at higher risk.

Pregnant women have increased vitamin A needs, malabsorption reduces uptake, and infants/children have growing needs.

Claim: Severe vitamin C deficiency leads to scurvy, a condition once common among sailors. While rare in developed countries today, mild deficiency can still occur.
Fact check: True. Scurvy is a condition caused by severe vitamin C deficiency.

Scurvy is now rare in developed countries because of availability of fruit and vegetable intake

Source: “Macroscopic features of scurvy in human skeletal remains: A literature synthesis and diagnostic guide” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6282809/

Claim: The risk of vitamin C deficiency in modern times is higher for certain groups, including smokers, those with limited food choices, and individuals with certain medical conditions.
Fact check: True. These groups are at higher risk of deficiency.

Smoking increases oxidative stress and increases the need for vitamin C. Restrictive diets or malabsorption can limit intake.

Claim: While consuming enough vitamins A and C is essential, consuming too much can be harmful, particularly with vitamin A, as excess intake can cause toxicity, especially from supplements.
Fact check: True. Vitamin A has a higher risk for toxicity, with supplements.

Fat-soluble vitamins are more likely to be stored and reach toxic levels. This is more common with supplementation.

Claim: Excess vitamin C is less of a concern because the body usually eliminates it through urine. However, very high doses can cause digestive issues like diarrhea and nausea.
Fact check: True. Excess vitamin C is usually excreted but can cause GI upset.

Excess Vitamin C is water soluble and not stored by the body. However large amounts can cause gastric distress.

Claim: It’s best to obtain vitamins from a balanced diet. If you’re considering supplements, consult a healthcare provider first to determine if they are needed and what dosage is safe.
Fact check: True. Dietary sources are preferable.

A balanced diet provides vitamins, minerals, and fiber. Supplements should be taken under medical guidance

Claim: Sometimes, dietary intake alone might not provide enough vitamins A and C, making supplementation necessary. However, supplementation should be approached cautiously.
Fact check: True. Supplements can sometimes be useful but should be approached carefully

Dietary intake should be prioritized, but supplements may be needed for some people. Caution should be exercised in order to avoid toxicity

Claim: Supplements can be beneficial for people with certain health conditions, such as those with malabsorption issues or restricted diets. Pregnant women and older adults may also benefit from supplements.
Fact check: True. Certain groups benefit from supplements.

Malabsorption and restrictive diets can hinder proper nutrition. Pregnant and older adults have increased nutritional needs.

Claim: When choosing supplements, consider the form and quality. Vitamin A supplements come as retinol or beta-carotene, while vitamin C supplements are typically ascorbic acid. Choose reputable brands and check for third-party testing.
Fact check: True. Form and quality should be considered when choosing supplements.

Retinol is a preformed vitamin A and beta-carotene is a provitamin A. Ascorbic acid is a common form of Vitamin C. Quality supplements are verified by third party testing

Claim: With supplements, remember that more isn’t always better. It’s important to stick to the recommended dosages unless a healthcare provider advises otherwise.
Fact check: True. It is crucial not to exceed recommended dosages.

High dosages do not provide extra benefit and may cause harm.

Claim: Vitamins A and C don’t work in isolation; they interact with other nutrients in the body, which can either improve or reduce their effectiveness.
Fact check: True. Nutrient interactions exist.

Nutrient interactions are complex. Some improve effectiveness and some may hinder efficacy.

Claim: Vitamin A works with vitamin D to support bone health and immune function, while vitamin E complements vitamin A’s antioxidant effects. However, too much vitamin A can interfere with vitamin D absorption.
Fact check: True. Vitamin A interacts with other vitamins.

Vitamin A and D are synergistic for bone health. Vitamin E complements the antioxidant activity of Vitamin A. Too much Vitamin A may reduce Vitamin D levels in the body

Claim: Vitamin C enhances iron absorption, particularly from plant sources, and works with vitamin E to protect cells from damage. High doses of vitamin C, however, might interfere with copper absorption.
Fact check: True. Vitamin C has some interactions with other nutrients.

Vitamin C is important for non-heme iron uptake. Vitamin C can have a negative affect on copper absorption with high supplementation

Claim: Understanding these interactions can help in making informed dietary decisions and highlights the importance of a balanced diet over isolated supplements.
Fact check: True. Balanced diet is preferred.

Dietary intake ensures nutrients interact naturally and provide the body with benefits that cannot be obtained with isolated supplementation.

Claim: Vitamin C may not prevent colds, but it might reduce their duration. Some studies show it can shorten colds by about one day.
Fact check: Mostly True. Vitamin C does not typically prevent colds, but may reduce duration.

Vitamin C does not prevent the common cold. Supplementation may shorten the duration of colds by 1-2 days.

Claim: It’s rare to get too much vitamin A from food alone. However, eating large amounts of liver regularly could lead to excess intake.
Fact check: True. Dietary Vitamin A toxicity is rare.

Dietary sources of Vitamin A are rarely toxic except with regular consumption of high retinol sources such as liver.

Claim: Cooking can reduce vitamin C content in foods. Steaming or microwaving vegetables can help retain more vitamin C compared to boiling.
Fact check: True. Cooking methods affect Vitamin C.

Vitamin C is water soluble and sensitive to heat, leading to loss during boiling. Steaming or microwaving retain more Vitamin C.

Claim: Vitamin A is essential for good vision, especially in low light. However, taking extra won’t improve vision if you’re not deficient.
Fact check: True. Vitamin A is essential for low-light vision, and excess will not provide additional benefit in non-deficient individuals

Adequate vitamin A intake maintains night vision. Deficiency can lead to night blindness.

Claim: These vitamins work well together and can be taken at the same time. However, it’s best to get them from a balanced diet when possible.
Fact check: True. They work well together and dietary sources are preferable

They have synergistic effects and it is not necessary to take them seperately. Dietary intake is preferred over supplements.

Claim: Yes, smokers need about 35 mg more vitamin C per day than non-smokers. Smoking increases oxidative stress, which vitamin C helps combat.
Fact check: True. Smokers have a higher Vitamin C requirement.

Smoking increases oxidative stress and vitamin C is used to combat oxidative damage.

Claim: Vitamins A and C are potent nutrients with wide-ranging benefits for health. They boost immunity and promote skin health, and their combined effects can be even more powerful.
Fact check: True. They are both important for overall health.

Both vitamins are important for maintaining health and together provide enhanced benefits

Claim: Although supplements can be useful, it’s often best to get these vitamins from food. A diet rich in fruits, vegetables, and some animal products can provide ample amounts, along with other beneficial nutrients found in whole foods.
Fact check: True. Food sources are preferred.

A varied diet provides vitamins, minerals, fiber, and phytochemicals, whereas supplements do not.

Claim: Maintaining balance is key when it comes to vitamins A and C. Insufficient intake can lead to deficiencies, while excessive intake can cause problems. Consult with a healthcare provider if you have concerns about your vitamin intake. They can offer advice tailored to your health needs.
Fact check: True. Balance is important.

Both deficiency and over-supplementation can lead to health problems. A physician should be consulted before making drastic diet or supplementation changes.

Claim: By understanding these vitamins and making informed choices, we can maximize their benefits for better health. Whether through diet or supplements, vitamins A and C can support our overall wellbeing in many ways.
Fact check: True. Vitamins A and C are important for overall health.

Vitamins A and C contribute to numerous bodily functions that are essential for overall health and wellness


Medically reviewed and fact checked

Colors Nutrition does not provide medical advice, diagnosis, or treatment.