Vitamin A
What is Vitamin A?
Vitamin A is a fat-soluble vitamin essential for many vital functions in the body.
It exists in two main forms:
Preformed Vitamin A (retinoids), found in animal products like liver and fish oils.
Provitamin A (carotenoids), found in plant-based foods, with beta-carotene being the most common.
Known for its role in maintaining healthy vision, Vitamin A also supports immune function, cell growth, and skin health.
What does Vitamin A do in our body?
Supports eye health by helping to maintain proper vision, especially in low-light conditions.
Plays a crucial role in the immune system, protecting against infections by maintaining the health of the skin and mucous membranes.
Assists in cell differentiation and healthy growth of skin, tissues, and organs.
Acts as an antioxidant (in its carotenoid form), helping neutralize free radicals and prevent cellular damage.
Supports reproductive health and proper fetal development during pregnancy.
Major Warning Signs of Vitamin A Deficiency
Night blindness – Difficulty seeing in dim light or darkness.
Dry eyes (xerophthalmia) – Can lead to severe vision problems and blindness if left untreated.
Frequent infections – Vitamin A deficiency weakens the immune system.
Dry, scaly skin – Reduced cell turnover and lack of moisture in the skin.
Other Deficiency Symptoms in Vitamin A
Slow wound healing – Reduced ability for skin and tissues to repair.
Poor growth in children – Linked to developmental delays due to its role in cell division.
Brittle hair and nails – Can be caused by a lack of proper cell growth and repair.
Respiratory infections – Due to weakened mucous membranes.
Vitamin A Deficiency in the Immune System
Vitamin A is vital for producing and maintaining white blood cells, which fight infections.
Deficiency can result in a weakened immune response, leading to frequent infections, especially in the respiratory and gastrointestinal tracts.
Increased risk of contracting measles and other viral infections in children.
Vitamin A Deficiency in the Cardiovascular System
Deficiency may lead to an imbalance in cholesterol levels, contributing to higher risk of cardiovascular diseases.
The antioxidant properties of Vitamin A (especially carotenoids) help to reduce oxidative stress, which is a factor in atherosclerosis.
Vitamin A Deficiency in the Integumentary System
Lack of Vitamin A can result in dry, rough, or scaly skin due to reduced production of natural oils.
Keratinization of the skin, where the outer layer becomes hardened, can occur, leading to further skin damage.
Can contribute to acne and other skin conditions due to its role in maintaining skin cell turnover.
Vitamin A Deficiency in the Lymphatic System
Vitamin A supports the healthy function of lymphoid tissues, which are essential for immune responses.
Deficiency can lead to reduced lymphocyte production, weakening the body’s defense mechanisms against infections.
Vitamin A Deficiency in the Endocrine System
Vitamin A plays a role in regulating the production of certain hormones, especially those related to the reproductive system.
Inadequate levels may affect thyroid hormone metabolism, leading to issues with energy and metabolism.
Vitamin A Deficiency in the Muscular System
Muscle weakness or diminished muscle repair can occur due to a lack of Vitamin A’s role in protein synthesis and cell growth.
Deficiency may impair muscle strength, particularly in growing children or athletes.
Vitamin A Deficiency in the Digestive System
A shortage of Vitamin A can lead to poor absorption of nutrients in the gut due to damaged mucosal lining.
Frequent gastrointestinal infections may occur due to weakened barriers against harmful pathogens.
Vitamin A Deficiency in the Nervous System
A healthy nervous system requires adequate Vitamin A for cognitive function and development.
Low levels have been linked to cognitive impairments and may increase the risk of neurodegenerative diseases.
Vitamin A Deficiency in the Skeletal System
In children, Vitamin A deficiency can lead to impaired bone growth and development.
It is also essential for maintaining bone density in adults, so a lack can contribute to osteoporosis or weak bones.
Vitamin A Deficiency in the Thyroid Pathway
Vitamin A influences thyroid hormone production and deficiency may contribute to hypothyroidism.
It can affect the metabolism and energy levels by interfering with proper thyroid function.
Low Vitamin A levels can give a false TSH reading.
Vitamin A Deficiency in the Liver
The liver stores Vitamin A, so deficiency can lead to impaired liver function.
Over time, chronic Vitamin A deficiency can result in fatty liver disease or compromise the liver’s ability to detoxify the body.
Causes of Vitamin A Deficiency
Inadequate dietary intake, particularly in regions with limited access to animal-based foods or fortified products.
Malabsorption disorders like celiac disease, Crohn's disease, or liver disorders, which inhibit the absorption of fats and fat-soluble vitamins.
Excessive alcohol consumption, which can deplete the body’s Vitamin A stores.
Physical Ailments Requiring more Vitamin A
Night blindness and other vision-related issues.
Chronic skin conditions like eczema or psoriasis.
Frequent infections or compromised immunity.
Delayed wound healing and skin repair issues.
Medications that Deplete Vitamin A
Orlistat (a weight loss drug) can reduce the absorption of fat-soluble vitamins, including Vitamin A.
Cholesterol-lowering medications (bile acid sequestrants) may also interfere with fat-soluble vitamin absorption.
Natural Supplements that Deplete Vitamin A
High doses of Vitamin D can interfere with Vitamin A balance.
Excessive zinc can increase Vitamin A utilization and depletion.
Heavy Metals that Deplete Vitamin A
Cadmium, found in cigarette smoke, can deplete Vitamin A levels.
Lead exposure may also contribute to reduced Vitamin A availability.
Testing Vitamin A
Vitamin A levels are typically measured through a blood test, which can assess serum retinol levels.
Liver biopsies may also be used in extreme cases to evaluate Vitamin A stores.
Daily Requirements of Vitamin A
For adult males: 900 micrograms (mcg) of retinol activity equivalents (RAE) per day.
For adult females: 700 micrograms (mcg) of RAE per day.
Higher amounts may be required during pregnancy or for individuals with specific health conditions.
Co-Factors Required for Vitamin A Absorption
Fats – As Vitamin A is fat-soluble, adequate dietary fats are necessary for absorption.
Zinc – Helps in the release of Vitamin A from the liver into the bloodstream.
Proteins – Essential for the transport of Vitamin A throughout the body.
Foods high in Vitamin A
Animal sources: Liver, eggs, and dairy products.
Plant sources: Carrots, sweet potatoes, spinach, kale, and other leafy greens (rich in beta-carotene).
Fortified foods: Certain cereals and dairy products are fortified with Vitamin A.
Things that affect the amount of Vitamin A in our food
Cooking methods – Excessive heat can degrade Vitamin A in food.
Storage – Prolonged storage, especially in sunlight, can reduce Vitamin A content.
Processing – Industrial processing of foods can strip away Vitamin A, particularly in fortified foods.
Other Random Information about Vitamin A
Vitamin A toxicity (hypervitaminosis A) can occur with excessive supplementation, especially from preformed Vitamin A sources, leading to symptoms like dizziness, nausea, or even liver damage.
Beta-carotene, the plant form, is much safer in excess, as the body only converts as much as needed into Vitamin A.
Final Thoughts…
One of the easiest ways to increase your Vitamin A is through Carrot Juice (cold pressed) but be sure to make your carrots organic. It is the one veg I consistently buy as organic as I have read reports that when a farmer ends up with fields that are too hard to plant any longer, they plant carrots to make the soil more friable. This happens because the carrots soak up all the poisins in the ground. Not entirely sure how true this is, but have seen it reported enough times that I won’t risk it… particularly for juice.
