What we call Vitamin A is actually a group of so called retinoids. (Retinol, retinal, and retinyl esters). Retinal in particular is critically important for maintaining normal vision. They are also needed for gene expression, reproduction, embryonic development, immune function, cell growth and differentiation and the maintenance of the lungs, kidney, and heart, among other organs.
Vitamin A comes in two main forms:
Provitamin A Carotenoids: Plant pigments, which are metabolized into the active forms of Vitamin A: Retinal and retinoic acid. The most important carotenoid (for us) beta-carotine, followed by the far less relevant alpha-carotene and beta-cryptoxanthin. The other forms (lycopene, lutein, and zeaxanthin) are not converted by our bodies.
Preformed Vitamin A (retinol & retinyl ester): Found in animal sources. Basically, the already converted provitamins. These are essential for pure carnivores such as cats, which lack the ability to process carotenoids.
This article will cover the recommended intake levels, why we want to reach those levels, the dangers of overconsumption, and which foods are richest in Vitamin A.
Note that all recommended intake figures below are based on the needs of a 31 year old non-pregnant, non-lactating woman on a 2000 kilocalorie diet. Your personal requirements may differ (wildly). One way to figure out your individual needs, including calories per day, is the FooDosage Nutrition Calculator. It’s free, by the way.
Recommended Vitamin A Intake
The recommended intake range for Vitamin A, as set by the National Academy of Sciences:
Recommended minimum Intake (RDA): 700 µg per day
Upper limit: 3000 µg per day.
Note that your personal requirements may differ depending on your age and sex. Lactating women in particular require higher amounts (1200-1300 µg).
Importance of an Adequate Vitamin A Intake (Dangers of a Deficiency)
As mentioned, Vitamin A has many functions in our bodies, including gene expression, reproduction, embryonic development, immune function, and cell growth. But its main function, and the one it’s most famous for is maintaining normal vision.
Side note: Vitamin A (and carrots) does not improve vision. It maintains normal vision. The corresponding myth was invented by the Royal Airforce as part of a confusion-propaganda campaign against the Germans. I’m sorry, but eating lots of carrots will not improve your eyesight, “just” help keep it at its current level.
As such, one of the greatest dangers of a Vitamin A deficiency is loss of vision, via xerophthalmia. Other dangers include an increased risk of diarrhea, as well as an increased severity and mortality of infections.
While severe Vitamin A deficiency is rare in developed countries, pregnant and lactating women should be especially careful to meet the minimum requirements, as adequate Vitamin A levels are necessary for normal fetal and child development.
Risks of an Excessive Vitamin A Consumption (Side Effects)
Being a fat soluble vitamin, respecting the upper limit for Vitamin A is more important than with water soluble ones, as excess amounts are stored in the liver, and cannot be disposed of as quickly. Liver toxicity is a main danger of Vitamin A overconsumption. Note, however, that this is only an issue for preformed Vitamin A. Carotenoids have not shown to cause these issues. Instead, an overdose of beta-carotene may give your skin an orange hue, but this is an aesthetic side effect.
Additionally to all the side effects associated with liver toxicity, consuming excessive amounts of Vitamin A has been associated with teratological effects on fetal development (growth retardation, delayed mental development or other congenital disorders), and osteoporosis (bone brittleness).
Special Considerations
Individuals with high alcohol intake, preexisting liver disease, hyperlipidemia or severe protein malnutrition may be distinctly susceptible to the adverse effects of excess preformed Vitamin A intake. Beta-carotene supplements are advised only to serve as a provitamin A source for individuals at risk of vitamin A deficiency.
Top Vitamin A Food Sources
The highest concentrations of Vitamin A are generally found in liver, dairy products, fish, darkly colored fruits, and leafy vegetables.
Some choice examples of Vitamin A rich foods:
Vitamin A Leaderboard – FooDosage Nutrition Calculator
Beef Liver (New Zealand)
Vitamin A per 100g (Boiled): 21’014 µg (3’002% of recommended minimum intake. WARNING: The upper limit for Vitamin A is 3000 µg per day. Try to keep your consumption below this level, at least as a weekly average.)
Calories per 100g: 150 kcal
Liver in general is extremely rich in Vitamin A. So rich, that you should only eat small amounts, to not exceed the upper limit. Since Vitamin A is fat soluble, this can be taken as a weekly average. Assuming your remaining diet is very low in Vitamin A, you should probably not exceed 50-100 grams of liver per week. Even less if you factor in the absurd amounts of Manganese it contains.
Other types of liver (beef from other countries, veal, goose, chicken, etc.) usually contain between 10’000 and 15’000 µg of Vitamin A.
But Vitamin A is not the only reason to limit liver consumption to very small amounts. Heavy metals such as arsenic, cadmium and lead, as well as pesticides tend to collect in farm animals’ livers. Try to only buy grass fed and organic to get “cleaner” livers, apart from all the other arguments for buying organic foods in general.
Beef liver is also an excellent source of:
- Manganese – at 328 mg / 100g (18’222% of recommended minimum intake. WARNING: The upper limit is 11 mg.)
- Cyanocobalamin (B12) – at 96 µg / 100g (4000% of recommended minimum intake)
- Copper– at 5.73 mg / 100g (637% of recommended minimum intake)
- Riboflavin (B2) – at 3.04 mg / 100g (276% of recommended minimum intake)
- Pantothenic acid (B5) – at 9.8 mg / 100g (196% of recommended minimum intake)
Eel
Example: Unagi (BBQ Eel) Eel – 25 Count – 14 Oz – Frozen – 10 Kilo Case (Amazon)
Vitamin A per 100g (Cooked, dry heat): 1137 µg (162% of recommended minimum intake)
Calories per 100g: 234 kcal
Not an everyday choice for most our pallets, eel is certainly worth a try for those who have never tasted it. Both in terms of taste and nutrition. If you like salmon, chances are you’ll like eel. As a fatty fish, it also sports a good amount of the Omega 3 fatty acids EPA & DHA, at 0.19 g / 100 g (76% of the daily recommended minimum)
Eel is also a good source of:
- Cyanocobalamin (B12) – at 2.89 µg / 100g (120% of recommended minimum intake)
- Phosphorus – at 277 mg / 100g (40% of recommended minimum intake)
- Niacin (B3) – at 4.49 mg / 100g (32% of recommended minimum intake)
- Zinc – at 2.08 mg / 100g (26% of recommended minimum intake)
Sweet Potato
Vitamin A per 100g (Baked): 961 µg (137% of recommended minimum intake)
Calories per 100g: 90 kcal
Sweet, sweet, baked sweet potato. What can we say? It’s delicious and a great source of Vitamin A. They also come with a fair bit of fiber, at 3.3g / 100g (14%).
Sweet potatoes are also a source of:
- Manganese – at 0.5 mg / 100g (28% of recommended minimum intake)
- Vitamin C – at 19.6 mg / 100g (26% of recommended minimum intake)
- Vitamin B6 – at 0.29 mg / 100g (22% of recommended minimum intake)
Carrots
Vitamin A per 100g (Boiled): 852 µg (123% of recommended minimum intake)
Calories per 100g: 35 kcal
Famous for their Vitamin A content, specifically beta-carotene, they even have their own myth about improving eyesight. No myth is that they’re one of the Vitamin A richest foods out there.
Carrots are also a source of:
- Vitamin K – at 13.7 µg / 100g (15% of recommended minimum intake)
- Vitamin B6 – at 0.15 mg / 100g (12% of recommended minimum intake)
- Dietary Fiber – at 3 g / 100g (12% of recommended minimum intake)
Pumpkin (Canned)
Example: Farmers Market Organic Pumpkin, 15 Ounce (Pack of 12)
Vitamin A per 100g (Boiled): 778 µg (111% of recommended minimum intake)
Calories per 100g: 34 kcal
Another great and practical source of Vitamin A, pumpkin contains more than three times as much Vitamin A per 100 g when canned as opposed to cooked.
Canned pumpkin also a source of:
- Vitamin K – at 16 µg / 100g (18% of recommended minimum intake)
- Copper – at 0.11 mg / 100g (12% of recommended minimum intake)
- Dietary Fiber – at 2.9 g / 100g (12% of recommended minimum intake)
Kale
Example: Cascadian Farm Organic Kale Vegetable, 10 Ounce — 12 per case.
Vitamin A per 100g (Boiled): 735 µg (105% of recommended minimum intake)
Calories per 100g: 30 kcal
At 30 calories per 100 grams, kale is a good choice for restricted calorie diets. As a side dish, it makes for a very healthy, vitamin packed addition to heartier meals.
Kale is also a great source of:
- Vitamin K – at 882 µg / 100g (980% of recommended minimum intake)
- Vitamin C – at 25.2 mg / 100g (35% of recommended minimum intake)
- Manganese – at 0.45 µg / 100g (25% of recommended minimum intake)
- Calcium – at 138 mg / 100g (14% of recommended minimum intake)
Butter
Vitamin A per 100g: 684 µg (98% of recommended minimum intake)
Calories per 100g: 717 kcal
Though not exactly recommended in great amounts, a little butter on your morning bread/toast/bagel will already contribute to your daily Vitamin A needs.
Butter is also a source of:
- Vitamin E – at 2.32 mg / 100g (15% of recommended minimum intake)
Spinach
Vitamin A per 100g (Boiled): 603 µg (86% of recommended minimum intake)
Calories per 100g: 34 kcal
For those who like the calorie and vitamin contents of kale, but not kale itself. Or for those who like spinach. Or both.
Spinach is also a great source of:
- Vitamin K – at 541 µg / 100g (601% of recommended minimum intake)
- Manganese – at 0.72 mg / 100g (40% of recommended minimum intake)
- Folate (B9) – at 121 µg / 100g (30% of recommended minimum intake)
- Magnesium – at 82 mg / 100g (26% of recommended minimum intake)
- Vitamin E – at 3.54 mg / 100g (24% of recommended minimum intake)
Goat Cheese (Hard)
Vitamin A per 100g: 486 µg (69% of recommended minimum intake)
Calories per 100g: 452 kcal
Cheese in general is a good source of Vitamin A, but hard goat cheese in particular contains about twice as much as most other cheeses like Swiss, and cheddar. As with most full fat cheeses, goat cheese contains a good amount of fat: 35 g / 100 g, of which 25 grams are saturated. On the other hand, it also comes with 30 grams of complete protein per hundred.
Goat cheese is also a good source of:
- Riboflavin (B2) – at 1.19 mg / 100g (108% of recommended minimum intake)
- Phosphorus – at 729 mg / 100g (52% of recommended minimum intake)
- Copper – at 0.63 mg / 100g (70% of recommended minimum intake)
- Sodium – at 423 mg / 100g (28% of recommended minimum intake. UL: 2300 mg)
Red Leaf Lettuce
Vitamin A per 100g: 375 µg (54% of recommended minimum intake)
Calories per 100g: 16 kcal
A favorite of bunny rabbits, Guinea pigs, and some people, The benefits of lettuce consist of mainly Vitamin A, and Vitamin K (140 µg, 156%). Green Leaf Lettuce contains slightly lower amounts, but more Vitamin C (9.2 mg, 12%) and Manganese (0.25 mg, 14%).
Drumstick Leaves
Example: Zen Principle Organic Moringa Leaf Powder, USDA Certified, 1 lb
Vitamin A per 100g (Boiled): 351 µg (50% of recommended minimum intake)
Calories per 100g: 60 kcal
Not exactly a widely available staple food, drumstick (moringa) leaves are certainly nutrient packed. Most commonly, they can be bought in powdered form, as a natural multivitamin. At 5 grams per hundred (cooked), they also contain a good amount of complete protein, considering the low calorie count of 60 per 100 grams.
Moringa leaves are also a great source of:
- Vitamin K – at 108 µg / 100g (120% of recommended minimum intake)
- Vitamin B6 – at 0.93 mg / 100g (71% of recommended minimum intake)
- Manganese – at 0.87 mg / 100g (48% of recommended minimum intake)
- Riboflavin (B2) – at 0.51 mg / 100g (46% of recommended minimum intake)
- Vitamin C – at 31 mg / 100g (41% of recommended minimum intake)
Garden Cress
Vitamin A per 100g: 346 µg (49% of recommended minimum intake)
Calories per 100g: 32 kcal
Vitamin packed, and many a kid’s first experimental foray into botany, cress makes a nice and tasty addition to salads and wraps.
Garden cress is also an excellent source of:
- Vitamin K – at 542 µg / 100g (602% of recommended minimum intake)
- Vitamin C – at 69 mg / 100g (92% of recommended minimum intake)
- Manganese – at 0.56 mg / 100g (31% of recommended minimum intake)
- Riboflavin (B2) – at 0.26 mg / 100g (24% of recommended minimum intake)
- Folate (B9) – at 80 µg / 100g (20% of recommended minimum intake)
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Bon Appetit 🙂
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