Vitamin A is a fat-soluble vitamin that can be found under many different names, including retinol, retinal and retinyl esters, as well as beta-carotene, a pro-vitamin which can be converted to vitamin A by the body. Vitamin A has many important functions, including the maintenance of proper vision, cell growth and the normal formation of the heart, kidneys, lungs and other vital organs [i,ii].
Women age 19 and older: 700mcg/day
Men age 19 and older: 900 mcg/day [i]
Vitamin A Deficiency
Vitamin A deficiency is incredibly rare in the developed world, but in developing countries it is the leading cause of progressive blindness due to a lack of food access. Cancer does not predispose one to an increased risk of deficiency, however those with pancreatic cancer should be aware of the signs of deficiency and ensure adequate intake of foods rich in all fat-soluble vitamins, not just vitamin A, as the pancreas is essential for the absorption of these vitamins in the body. Signs of deficiency include night blindness or an inability to see in low light situations. Some studies have suggested that vitamin A may decrease the risk of developing various cancers, particularly pancreatic cancer, although the results are still inconclusive [iii].
Excessive intake of fat-soluble vitamin supplements is not recommended, as it takes your body a much longer time to excrete them than water-soluble vitamins. Because of this, getting your fat-soluble vitamins from food sources is an excellent way to avoid nutrient deficiencies while preventing an overdose or toxicity [i,ii].
** If instructed by a medical professional to take a vitamin or mineral supplement, it is important that these instructions are followed. In some cases, food sources of vitamins and minerals will not be sufficient for addressing nutritional inadequacies. **
Sources of Vitamin A
Below is a list of the most common food sources of vitamin A [i].
- Sweet potato
- 8 pounds cherrystone clams, scrubbed clean or two 10 ounces cans canned clams and 6 cups of bottled clam juice
- 1 tablespoon unsalted butter
- 2 celery stalks, chopped
- 1 large onion, chopped
- 1 garlic clove, minced
- 2 ½ pounds of potato, peeled and cut into ½ inch pieces
- 1 tablespoon chopped fresh thyme
- 1 bay leaf
- 2 tablespoons cornstarch
- 1 cup heavy cream
- 1 cup 2% milk
- Salt and pepper to taste
- Chopped fresh chives (optional)
- Oyster crackers (optional)
- Bring clams and 4 cups of water to a boil in a large pot. Cook until the clams open, (8-10 minutes, discard any that remain closed). Using a slotted spoon, transfer the clams to a baking sheet and let cool. When able to handle, pull the meat from the shells.
- Chop the clams into bite-size pieces. Strain the broth through a mesh colander. Add additional water so that broth equals 6 cups of fluid. If using canned clams you may skip steps 1 and 2.
- In a large pot, melt butter over medium heat. Add celery, onion and garlic and stir often, cook until onions are translucent (about 10 minutes). Add the reserved broth (or 6 cups of clam juice), potatoes, thyme and bay leaf. Bring the chowder to a simmer and cook until the potatoes are tender (about 20-25 minutes). Stir cornstarch and 2 tablespoons of water in a small bowl to form a slurry. Add the slurry to the chowder base and return to a boil to thicken.
- Remove the pot from the heat to avoid curdling the milk. Remove the bay leaf. Stir in the chopped clams and cream. Season with salt and pepper to taste.
- Garnish with chives and oyster crackers
[i] Vitamin A: Fact Sheet for Health Professionals 2018; https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/#h6.
[ii] Vitamin A. 2018; https://www.mskcc.org/cancer-care/integrative-medicine/herbs/vitamin.
[iii] Huang X, Gao Y, Zhi X, Ta N, Jiang H, Zheng J. Association between vitamin A, retinol and carotenoid intake and pancreatic cancer risk: Evidence from epidemiologic studies. Sci Rep. 2016;6:38936.