Vitamin A | How Much | Benefits | Fertility | Immunity | Skin | Eyes
Although vitamin A is one of the most versatile and potent vitamins for health, most people know little about its benefits.
For this reason, I will explain the health benefits of vitamin A and how you can reap them based on recent studies.
What Are Vitamin A Benefits?
Vitamin A is necessary to guarantee the proper functioning of the following processes in the human body:
- Maintenance of healthy vision
- Growth and development of babies in the womb
- Ensuring organ and immune function
- Supporting muscle development
- Protection against free radicals
Therefore, if you don’t get enough vitamin A from your diet, you may experience the following deficiency symptoms:
- Immunodeficiency and risk of infection
- Hair loss
- Blemished skin and acne
- Night blindness
- Dry eyes
Accordingly, vitamin A deficiency is one of the leading causes of blindness in developing countries.
How Much Vitamin A per Day?
Health authorities recommend that men consume 900 mcg, women 700 mcg (770 mcg during pregnancy), and children and adolescents 300 to 600 mcg of vitamin A per day (ODS 20201).
How Much Vitamin A Is Too Much?
Although vitamin A toxicity is possible and harmful, it is implausible, especially if consumed in natural foods.
Accordingly, vitamin A poisoning occurs when people consume excessive amounts of synthetic supplements daily for months.
True Vitamin A Benefits Are From Retinol
The active form of vitamin A is also known as retinol, which you may associate with cod liver oil.
Nevertheless, cod liver oil offers reasonable benefits since the liver is generally the best natural source of active vitamin A1.
In contrast, most internet sources and even books will consistently suggest the following vegetables to you as excellent sources of vitamin A:
- Sweet potatoes
However, although these orange plants are considered vitamin A foods, they only provide a precursor to vitamin A: beta-carotene.
For this reason, beta-carotene is also known as provitamin A.
Provitamin A vs. Vitamin A
Since nutritional claims do not distinguish between provitamin A and true retinol, they are highly misleading.
Nevertheless, to meet our daily requirement of vitamin A, we must consume real vitamin A foods that contain retinol.
Therefore, it is crucial to know the difference between retinoids and carotenoids.
Retinoids are substances closely related to retinol due to their chemical structure and activity.
On the other hand, carotenoids are fat-soluble pigments that give carrots their color, for example. While animal sources provide retinol, plant sources only have carotenoids, such as beta-carotene.
Since the preformed vitamin A from animal sources has much higher bioavailability, the body can utilize it better.
In contrast, the body must first convert provitamin A from plant sources into retinol if it can do so.
On the one hand, the conversion is often only possible to a limited extent in people with digestive problems, hormone disorders, or diabetes.
On the other hand, according to studies, women can absorb only about 3.3% and men about 2.25% of beta-carotene (Lin et al. 20002; Hickenbottom et al. 20023).
Furthermore, your body needs to convert these absorbed carotenoids to retinol further.
The bottom line is that only minimal amounts of beta-carotene can be converted to vitamin A by the body.
For example, in this study, only 3% of absorbed beta-carotene was converted to retinol (Hickenbottom et al. 20024).
Furthermore, about 45% of women and men can barely convert beta-carotene to vitamin A (Lin et al. 20005; Hickenbottom et al. 20026).
If you are still convinced that carrots and sweet potatoes are prime sources of vitamin A, you should better be ready to eat several pounds of them daily.
Which Foods Can Offer Vitamin A Benefits?
Although beta-carotene is an antioxidant, it is not a proper vitamin A. Therefore, plants, unfortunately, do not qualify as retinol sources.
For this reason, we should instead eat foods with preformed vitamin A to meet our daily requirement of this essential nutrient.
Some of the best foods that contain vitamin A include:
- Calf’s liver
- Goose liver
- Cod liver
- Goat cheese
- Grass-fed butter
- Free-range eggs
- Blue cheese
With this in mind, regular consumption of pasture-raised liver is the most effective way to obtain optimal vitamin A levels.
If you want to consume the very highest quality, dine on wild livers, such as those from deer or reindeer (Hassan et al. 20127).
Because of its unparalleled nutrient density, recent studies even recommend that adults eat liver several times a week (Kicinska et al. 20198).
Moreover, vitamin A is also essential for children.
Accordingly, a single consumption of 66 grams of liver per month could render vitamin A supplementation obsolete for preschoolers in South Africa (van Stuijvenberg et al. 20209).
Thus, even small amounts of retinol can affect your health.
Is Vitamin A Water or Fat Soluble?
Vitamin A belongs to the group of fat-soluble vitamins. Therefore, we cannot absorb vitamin A properly without a low-fat diet.
Furthermore, fat can increase the poor conversion of carotenoids into usable vitamin A.
However, as we can see from the previous list of vitamin A foods, nature leaves nothing to chance. All of these natural foods are rich in fat and vitamin-A as well.
In particular, healthy animal fats such as grass-fed butter or organic lard help absorb and convert to retinol.
Health Benefits of Vitamin A
Although vitamin A is one of our planet’s most critical nutrients, few people know its benefits.
Why retinol is indispensable in all stages of life – from the fetus to old age – shows us the comprehensive health benefits of vitamin A.
Vitamin A is essential for developing vital organs and a child’s growth during and after pregnancy (Hadi et al. 200010).
Low vitamin A levels at the child’s birth are significant if the mother’s vitamin A intake is inadequate during pregnancy.
As a result, the immune function is lower, and child mortality is higher due to infectious diseases such as diarrhea, measles, and respiratory infections.
Nonetheless, according to research, pregnant women should avoid synthetic vitamin A supplements because they could cause malformations (Guillonneau et al. 199711).
Similarly, animal studies examining the importance of vitamin A in reproduction have found that retinol deficiency can limit fertility in both women and men.
While in males, sperm quality is impaired, in females, it is that of the oocytes (Clagett-Dame et al. 201112).
2. Immune System
When it comes to the immune system, vitamin C is always in the spotlight.
Nonetheless, vitamin A deserves more attention since scientists originally discovered it as the anti-infection vitamin (Green et al. 192813).
For example, the intestinal wall relies on vitamin A to form and maintain cells (Huang et al. 201814).
And this barrier is essential in keeping pathogens away from vital organs.
Thus, the intestinal wall is better protected from lectin attacks, such as gluten, damaging it (Sturgeon et al. 201615).
In this context, sufficient bioavailable retinol consumption helps to ensure intact immune function and prevent pathogens’ transport to critical zones.
Furthermore, even mild vitamin A deficiency can promote the risk of respiratory disease and diarrhea (Sommer et al. 198416).
According to this recent study, vitamin A in the diet reduces infections and mortality associated with pneumonia, tuberculosis, or malaria (Huang et al. 201817).
3. Skin, Face, and Acne
Retinol is an antioxidant that protects skin cells from oxidative stress, such as UV rays. Accordingly, it can slow the aging process, promote skin renewal, smooth it, and counteract acne (Park 201518).
Accordingly, recent studies recommend natural foods rich in zinc, and vitamins A and E to fight acne (Ozuguz et al. 201419).
This recommendation’s good news is that these nutrients are found in vitamin A’s natural sources, such as beef liver.
Furthermore, organ meats also provide collagen, an essential building block of healthy skin.
Retinol forms the eye’s retina pigments and is essential for good vision, especially night vision and overall eye health.
Therefore, it is probably no coincidence that we call this part of the body retina.
Damage to the retina from oxidative stress-so-called age-related macular degeneration, is the most common cause of vision loss in the elderly population (Beatty et al. 200020).
Although we are all familiar with the old truism that carrots are good for the eyes, it may not be entirely true.
According to a recent study, beta-carotene alone cannot inhibit vision decline caused by age-related macular degeneration (Evans et al. 201721).
In contrast, pediatricians and nutritionists rely on vitamin A. Accordingly, vitamin A distribution programs save the eyesight and lives of nearly half a million children annually (Sommer 201422).
Vitamin A deficiency is among those nutritional deficiencies with the most pertinent worldwide impact.
In addition to infectious diseases, insufficient intake of vitamin A mainly promotes chronic inflammation in the body.
For this reason, the anti-inflammatory effect of vitamin A plays an essential role throughout the body, from the skin to the lungs to various precancerous conditions (Reifen 200223).
Calcium gets most of the attention when it comes to strong bones.
Yet vitamin A intake plays just as crucial a role in bone formation and growth.
While people with lower blood levels of vitamin A have a higher risk of bone fractures, those with the highest vitamin A levels have a lower risk (Zhang et al. 201724).
In addition to retinol, vitamin D consumption is equally crucial to strengthening bones and minimizing fractures’ risk (Joo et al. 201525).
Therefore, it is natural sources of vitamin A, such as free-range eggs or cod liver, that make the difference, as they contain both nutrients.
7. Muscle Gain and Weight Loss
Vitamin A was initially known to be essential for animal growth. And indeed, retinol plays a supporting role in protein, fat, and carbohydrate metabolism (Chen et al. 201426).
Accordingly, scientists discovered decreased muscle protein synthesis in rats that consumed too little vitamin A through diet (Narbonne et al. 197827).
Thus, against this background, vitamin A could lead to muscle wasting. In contrast, vitamin A intake directly promotes children’s growth (Hadi et al. 200028).
However, vitamin A may help not only in muscle gain but also in fat loss.
Researchers concluded after monitoring young adults’ blood pressure, blood levels, and diet.
According to their findings, vitamin A deficiency in the diet may directly correlate with obesity (Zulet et al. 200829).
Most people are not aware that your diet can have a direct impact on your genome.
Vitamin A regulation of gene expression is an excellent example of how nutrients can directly influence gene expression.
Accordingly, the bioactive components of retinol can directly regulate genes (McGrane 200730).
For this reason, the way you eat may change your genes over time.
After genes are parts of your DNA, they are passed on to your offspring. In the process, they guide how proteins are built and bodily functions are regulated.
Cancer is a disease based on the uncontrolled growth of abnormal cells. Damage to the DNA of regulatory genes induces these changes in the development and constitution of cells.
Most animal studies suggest retinoids can prevent and suppress cancer (Sankaranarayanan et al. 199631).
Similarly, other studies state that retinoids can suppress cells’ transformation, inhibit organ carcinogenesis, and prevent second primary tumors’ development (Sun et al. 200232).
In contrast, vitamin A supplements based on beta-carotene do not have the same effect as natural foods containing retinol (Lee et al. 199933).
10. Blood Production
Vitamin A also plays a significant role in stem cell modification. Recent research indicates that retinol supports stem cells’ self-renewal, including embryonic stem cells (Khillan 201434).
Moreover, another study suggests that retinoids help regulate those necessary stem cells to keep producing new blood cells (Purton 200735).
Accordingly, vitamin A deficiency can cause a loss of important blood stem cells.
This may damage the hematopoietic system responsible for blood production in the bone marrow, say scientists at the German Cancer Research Center (Cabezas-Wallscheid et al. 201736).
Moreover, low retinol levels can contribute to anemia (Jafari et al. 201337).
Do Not Underestimate the Benefits of Vitamin A
While the Internet, pharmacies, and even supermarkets promote vitamin C, hardly anyone promotes the potential health benefits of vitamin A.
Nevertheless, retinol is essential for the immune system, reproduction, eyesight, and skin. Hence, vitamin A deficiency is also a severe global issue.
You must turn to natural vitamin A foods to get enough active retinol into your body.
In this context, animal products are the key to health since humans may only convert beta-carotene from plant sources into active vitamin A in insufficient amounts.
Vitamin A Benefits FAQ
What is vitamin A good for?
The benefits of vitamin A may support your immune system, skin, eyes, blood, muscle gain and fertility.
How much vitamin A is too much?
It’s hard to overconsume natural foods with vitamin A. Instead, most vitamin A poisoning cases occur when people consume synthetic supplements in excessive amounts daily for months. Health authorities recommend daily consumption of 900 mcg vitamin A for men and 700 mcg for women.
Can I take vitamin A everyday?
You can take vitamin A daily if you consume natural foods containing vitamin A. Be aware that rare vitamin A toxicity cases are induced by excessive daily intake of supplements.
What does vitamin A do for your face?
Vitamin A helps the skin to regenerate and protect itself from UV rays. Besides, retinol is known to fight acne.
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