Vitamin A (retinol) is one of the most important vitamins for humans. It plays an essential role in the development of our eyes and skin. The human body needs it to make new cells, maintain healthy bones and teeth, fight off infections, and many other things. Humans need vitamin a to grow properly. Too little vitamin a can cause blindness or even death if not treated immediately with proper medication.
The human body makes its own vitamin a from retinal pigments called retinoic acid. These pigments are found in the rods and cones of the retina. Retinoids act like hormones to regulate these pigment cells so they produce enough of their active form, known as retinoic acid. There are two types of retinoid: alpha- and beta-carotene derivatives. Alpha-carotene is converted into vitamin A in the liver.
Beta-carotene is converted into vitamin A in the intestines. Both types of carotenoids are used by our bodies to make vitamin a.
How Much Vitamin A Are You Getting?
The amount of retinol you get from food depends on several factors such as your age, gender, and ethnicity. Most of the vitamin A in your body is stored in your liver and fat cells. The liver breaks down the fat-soluble vitamins to make them available for use by other parts of the body. It can take up to six months for all the vitamin A stored in your body to be used up.
The amounts of vitamin A in food are measured in retinol activity equivalents (RAE). Many foods contain a combination of three types of vitamin A:
Retinol: animal-based; found in liver, milk, and eggs.
Retinal: plant-based; found in colorful fruits and vegetables like cantaloupes, carrots, and apricots.
Carotene: plant-based; found in carrots, sweet potatoes, and spinach.
One microgram (mcg) of retinol is equal to 1?
000 of an equivalent of retinal or carotene. Carrots, for example, contain around 3,000 mcg of alpha-carotene, which is the same as 0.5 mcg of vitamin A.
Here are some more food comparisons for you to think about:
3 1/2 oz. cooked lean pork contains 2,000 mcg of retinol.
One large egg contains 0.6 mcg of retinol.
One cup of whole milk contains 0.38 mcg of retinol.
It is possible to get 1,000 mcg of vitamin A in just one carrot!
You can meet or exceed the daily value of vitamin A by eating just a single serving of many foods. If you are concerned about getting enough of this important vitamin, choose a variety of different food sources.
Eating a well-rounded diet will help you get all the nutrients your body needs. Just remember that you only need 2,000-3,000 mcg of retinol per day. It is very easy to get too much of this vitamin, which becomes a problem.
Too much of a good thing
Taking in too much retinol can lead to toxic levels in the body. It can take months or even years before the symptoms are noticeable, but they will get worse over time. In most cases, the symptoms are reversible if you cut out the cause of the overdose.
Too much retinol can lead to:
Sun Sensitivity. Eating too many carrots can make your skin more sensitive to the sun. While you may think that you are getting a healthy dose of both vitamin A and antioxidants, you are actually just increasing your chances of getting skin cancer.
Skin conditions like acne, dermatitis, or dryness can also be caused by eating too many carrots, which in turn might make you shy away from social situations.
Cataracts. Getting too much retinol can cause the lens of your eyes to become less transparent. This can lead to vision problems and make it harder for you to see. Cataracts are also caused by aging, but eating plenty of carrots won’t make them go away any sooner.
Blood Clots. Vitamin A is necessary for normal blood clotting. Eating too many carrots can make it harder for your blood to clot, which can cause a risk of bleeding.
It can be tempting to take in more than the recommended daily amount of any nutrient, but this can lead to unpleasant side effects. Eat a balanced diet and you’ll be doing your body a favor.
How can you get the most out of your food?
Try these ideas for starters:
Eat a well-rounded diet that includes fruits and vegetables. Don’t overdo it with the carrots, though!
Choose a variety of foods that are high in vitamin A. This will help you get the nutrients your body needs without getting too much of any one thing.
Cut back on foods that have been pre-processed. Most food manufacturers add extra nutrients to their products, which means that you don’t have to. Stick with whole foods instead and you’ll get the same (or better!) benefits!
Take a daily multivitamin. There’s no way to know if you’re getting all of the vitamins and nutrients your body needs, but a daily multivitamin is a simple way to fill in the gaps.
If you have any other questions about eating right, just ask us! We’ll do our best to help you out.
This article was written by our editorial staff with contributions from readers like you. Give us your feedback, then browse our other articles about nutrition and health.
Photo by janeb1382
Sources & references used in this article:
More than just food: Food justice and community change by G Broad – 2016 – books.google.com
Impact of massive doses of vitamin A on nutritional blindness in Bangladesh by N Cohen, H Rahman, M Mitra, J Sprague… – … American journal of …, 1987 – academic.oup.com
Telephone health care: It’s more than just a phone call by K Smith – Pediatric Nursing, 1999 – search.proquest.com