27 Oct 2013

Let’s talk about vitamins. We all know the word “vitamins,” but what does it mean? What makes a nutrient a vitamin? The definition of a vitamin is: an essential nutrient that is different from protein, carbohydrate, and fats; it occurs naturally in foods in very small amounts; it cannot be made by the body; it is needed for the body to stay healthy; and if the body doesn’t get enough vitamins, deficiencies will occur. For example if you don’t get enough vitamin C you get scurvy, inadequate vitamin D can lead to rickets, and too little vitamin E may result in problems walking. So getting enough of all vitamins is so important.

There are two kinds of vitamins-water-soluble meaning these vitamins get into the body with water and fat-soluble vitamins, which get into the body attached to fat. Getting enough fat-soluble vitamins into the body can be a challenge for persons who have CF because they cannot absorb fat unless they take pancreatic enzyme capsules. So to get sufficient fat-soluble vitamins people who have CF need to take multivitamins designed just for them with a fat-containing food or drink and enzymes.

Today we will review vitamin A. In future issues we will review the other fat-soluble vitamins, D, E, and K. Vitamin A is known as retinol and comes in two forms. One is called “preformed” and found in meats (especially liver), poultry, fish and dairy products. The second form is called “provitamin A” or carotenoids and is found in fruits and vegetables, especially those that are bright orange or deep green.

Vitamin A has many roles in health: normal vision, bone and tooth formation, cell function, and immunity. The carotenoids act as antioxidants. Vitamin A works in the lining of the lungs to help fight infection. It also helps keep the intestines healthy. Not getting enough vitamin A can lead to night blindness. This means your eyes cannot adjust when going from a lighted area to a dark area, such as when you enter a movie theater. Night blindness is a major symptom of vitamin A deficiency, which you can notice, but other symptoms might not be so easy to notice. Without enough vitamin A your body may not be able to fight infections as well as it could if it had enough vitamin A.

Since people who have CF cannot absorb the fat-soluble vitamins, including vitamin A, as easily as people who do not have CF the vitamins designed for CF contain more vitamin A. The MVW Complete Formulation multivitamins contain a mixture of retinol and beta-carotene at a level needed by persons who have CF and in a form, which may make it easier to be absorbed. To be sure the body absorbs the vitamin A it is best to take the MVW Complete Formulation Multivitamins with fat containing food and/or drink and enzymes

Taking too much vitamin A, especially as retinol can cause bone and liver problems. On the other hand, beta-carotene is safer. Pregnant women need to be careful not to take too much retinol daily, since it may be harmful to the developing baby. It is best to work with your CF Healthcare Team to decide how much vitamin A is right for you.

Food Sources of Vitamin A

  • Beef liver and other organ meats. These foods have so much preformed vitamin A that you can actually get too much of the vitamin. Best not to eat daily.
  • Fish such as salmon.
  • Green leafy vegetables and other green, orange, and yellow vegetables such as broccoli, carrots, and squash.
  • Fruits, including cantaloupe, apricots, and mangos.
  • Dairy products.
  • Fortified breakfast cereals.

Please let us know if you have any questions about vitamin A.  You can send your questions through our contact form.