What’s Up With Vitamin A?

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What’s up with vitamin A and cronometer.com? I have one lousy small carrot and I am at 278% of my daily requirement for vitamin A. Is that correct? And to add to it all, vitamin A is supposedly toxic at high doses. First, it is correct, and in this blog I will address what is going on and shed some light on what is up with vitamin A.

Carrots, spinach, kale, bell peppers, sweet potatoes, cantaloupe, apricots, broccoli, tomatoes, and asparagus are all excellent sources of vitamin A. Vitamin A will preserve and improve your eyesight and help you fight off viral infections. It is known as the “anti-viral vitamin”. It is also a fat-soluble vitamin and needs fat to dissolve it and transport it within the body. Deficiencies may be caused by a diet that is extremely low in fat.

There are two different types of vitamin A. The first type, preformed vitamin A (retinol), is found in meat, poultry, fish, and dairy products. The second type, provitamin A (carotenoids), is found in fruits, vegetables, and other plant-based products. The most common type of provitamin A in foods and dietary supplements is beta-carotene.   Preformed vitamin A and provitamin A is where the confusion comes in.

Toxicity can occur with excessive intakes of preformed vitamin A (retinol) and not necessarily with provitamin A (carotenoid) intake. The dosage levels that need to be obtained to cause toxicity are difficult to attain through food alone. Toxicity usually has been associated with prolonged supplement intake over a long period of time.

Symptoms of getting too much preformed vitamin A (retinol) can cause dizziness, nausea, headaches, coma, and even death according to the National Institute of Health (NIH).

Consuming high amounts of provitamin A can turn the skin yellow-orange in color, but this condition is harmless.

In cronometer (CM) you can click on “vitamin A” and open a box that displays the daily recommended intakes (DRI), which are CM’s default settings. The range in the picture is for a fifty-year-old male.  These are also editable and you can put any range you desire into them.

Vitamin A

The DRI’s and tolerable upper limits (UL) for preformed vitamin A can be found on the site www.nap.edu.   There are no limits established for provitamin A (carotenoids, beta-carotene).

We get a lot of questions when one carrot reflects 278% of your daily value, but we here at cronometer.com can’t tell you what amount to take or what ranges to use. That decision is left to you and your healthcare team. We hope this blog will help you understand why CM states what it does and what it means allowing you to be better informed and make the decision that is best for your health.

Live well!

Frank Alvarez


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