Everything You Need to Know About Vitamin A

Vitamin A is an essential nutrient that plays a crucial role in maintaining good eye health, promoting cell growth, and strengthening the immune system. It is particularly vital for the reproductive health of both men and women, as it is involved in the formation of sperm and eggs, as well as the growth of fetal tissues. Thus, It is integral for the well-being of pregnant people and their developing children, as well as for women who are attempting to conceive.

Furthermore, vitamin A possesses antioxidant properties. Antioxidants are compounds that may shield your cells from the damaging effects of free radicals  which are created when your body metabolizes food or due to exposure to tobacco smoke and radiation. Free radicals are believed to contribute to conditions such as heart disease, cancer, and other illnesses.

In addition to its other benefits, it aids in the maintenance of healthy skin, teeth, and hair, as well as enhances the immune system. If you’re not getting enough Vitamin A, you can develop symptoms like night blindness, dry, coarse hair and an increased susceptibility to respiratory infections.

While it’s essential to avoid a deficiency in vitamin A, it’s equally important to prevent excess intake. We will guide you through the recommended daily intake of vitamin A for optimal health and discuss the potential risks associated with consuming too much.

Sources

There are two main types of vitamin A:

Preformed vitamin A: This is predominantly found in animal foods like liver, eggs, fish, and dairy. These sources are rich in retinol or retinyl esters, which the body readily absorbs.

Provitamin A: Plant-based foods like carrots, sweet potatoes, and leafy greens are high in carotenoids, such as alpha-carotene and beta-carotene, which your body can transform into active vitamin A forms that are easily absorbed.

Your body cannot produce Vitamin A on its own, so it’s crucial to get it from diet or through supplements. To ensure you’re meeting the daily requirement , it’s important to eat a variety of foods, including:

• Some types of fish, such as herring and salmon
• Organ meats, including liver
• Leafy greens such as spinach, collard greens and Kale.
• Vegetables such as sweet potatoes, carrots, bell peppers, broccoli, avocado and winter squash.
• Fruits, including cantaloupe, mangos, and apricots.
• Dairy products such as milk and cheese.
• Eggs

Supplements

If you find it challenging to meet the daily recommended intake of Vitamin A through your diet, you may consider using supplements as advised by your healthcare provider. They are usually available in the principal forms of retinyl palmitate and retinyl acetate.

These supplements are offered in various dosages within the safe upper limit, also known as the tolerable upper limit, being 10,000 IU. To avoid potential side effects and interactions with other medications, it is advisable to only consume dietary supplements under the supervision of a qualified healthcare professional.

Recommended Vitamin A Requirement Per Day:

According to the NHS, the appropriate vitamin A requirement for adults aged 19 to 64 per day is:

700 mcg for men
600 mcg for women

The overall amount of Vitamin A level in food is typically shown in micrograms (µg/mcg) of retinol equivalents (RE). The amount of vitamin A you need depends on your age, sex, and other factors such as pregnancy. Please refer to the following table and consume accordingly.

*Adequate Intake

Vitamin A Toxicity- Hypervitaminosis

The condition resulting from vitamin A overdose is known as hypervitaminosis A. This condition may be acute or chronic. Acute toxicity occurs after consuming large amounts of vitamin A over a short period of time. In contrast, chronic toxicity develops when excessive amounts of vitamin A accumulate in the body over an extended duration.

Although vitamin A is crucial for various bodily functions, excessive intake can pose risks. Excessive consumption beyond the recommended level can be harmful as it is a fat-soluble vitamin that your body stores instead of excreting. The symptoms listed below may indicate Hypervitaminosis:

• Dry skin, lips, and eyes
• Skin irritation (like skin peeling, redness)
• Hair loss
• Blurry vision 
• Weaker bones
• Headache
• Nausea 
• Vomiting
• Dizziness
• Elevated cholesterol levels

Excessive intake during pregnancy may lead to birth defects like abnormalities in the eyes, heart, lungs, or skull. In rare instances, Hypervitaminosis can result in liver or kidney damage, severe muscle and joint pains. If you notice any of these symptoms, it’s crucial to consult your healthcare provider immediately. Therefore, before taking any supplement, it is always advisable to check with your healthcare provider.

Recognizing and Addressing the Risks of Vitamin A Deficiency

Vision Health:

• A deficiency in vitamin A can result in various vision-related problems.
• Night blindness, a preliminary sign of deficiency, makes it challenging to see clearly in dimly lit environments.
• If not treated, it can progress to xerophthalmia, a condition marked by dryness and thickening of eye’s lining and cornea.
• For individuals who spend considerable amounts of time in front of screens, it’s crucial to include foods high in vitamin A in their meals.

Prenatal and postnatal development

• Both excessive and insufficient levels of vitamin A are associated with the occurrence of birth defects.
• While adequate intake of vitamin A is crucial for optimal reproductive health. Deficiency can lead to infertility and hinder growth and development in children.
• Additionally, It is instrumental in preventing birth defects and lowering the risk of infertility. It is vital for reproductive health in both males and females, as it contributes to the development of sperm and eggs.
• Additionally, it is essential for the health of the placenta, the development and maintenance of fetal tissues, and overall fetal growth.
• Consequently, It is fundamental to the well-being of pregnant individuals and their developing babies, as well as those attempting to conceive.
• However, excessive intake during pregnancy can adversely affect the fetus, leading to birth defects and an increased risk of infections and diseases.
• Pregnant individuals should avoid consuming foods high in vitamin A, such as pâté and liver, along with vitamin supplements.

Immunity Impact:

• Vitamin A deficiency compromises the immune system, increasing susceptibility to infections.
• It plays a vital role in health by regulating oxidative stress, enhancing immune function, and providing protection against certain diseases.
• The immune system comprises a complex array of cells that work to maintain health, and vitamin A is essential for facilitating communication among these cells to combat pathogens and infections.
• Symptoms of deficiency may include frequent respiratory infections, dry skin, and an elevated risk of illness.

Potential complications

A long-term deficiency may elevate the risk of respiratory diseases (such as pneumonia) and infections (such as measles and diarrhea). Additionally, It can also cause anemia (a condition in which the red blood cells do not supply enough oxygen to the body). In severe cases, not getting enough vitamin A can also lead to death.

Addressing Deficiency:

• Increase intake of vitamin A-rich foods such as carrots, sweet potatoes, and leafy greens.
• Supplements may be considered for individuals who are unable to fulfill their requirements through diet alone.
• Caution: It is advisable to consult a healthcare professional prior to taking supplements to avoid toxicity from excessive intake.