Vitamin A, D and E: Functions, Food Sources & Daily Needs

Understanding vitamin A, D and E is essential for anyone looking to optimize their nutrition through evidence-based strategies. These three fat-soluble vitamins play critical roles in vision, immune function, bone health, and cellular protection — yet deficiencies remain surprisingly common worldwide. Whether you're building a personalized nutrition plan or interpreting your latest blood work results, knowing how these vitamins work together can transform your dietary approach.

By Sarah Chen, RD · Reviewed by Dr. James Patel, MS, RDN · Published March 28, 2026 · Updated March 28, 2026


Key Takeaways


What Are Vitamin A, D and E?

Vitamin A, D and E belong to the group of fat-soluble vitamins, meaning they dissolve in fat rather than water and are stored in your liver and fatty tissues. Unlike water-soluble vitamins (like vitamin C and the B vitamins), your body doesn't excrete excess fat-soluble vitamins easily, which means both deficiency and toxicity are important considerations [1].

Each of these three vitamins serves distinct biological functions:

Understanding how vitamin A, D and E interact is key to building a metabolic profile that truly reflects your body's needs. Research suggests these vitamins may work synergistically — for example, vitamin D enhances calcium absorption while vitamin A supports the mucosal barriers that regulate nutrient uptake [4].

Vitamin A: Functions and Food Sources

Vitamin A exists in two primary forms in the diet: preformed vitamin A (retinol) found in animal products, and provitamin A carotenoids (beta-carotene) found in colorful fruits and vegetables [1].

Key Functions of Vitamin A

Top Food Sources of Vitamin A

Food Serving Size Vitamin A (mcg RAE) % Daily Value
Beef liver 3 oz (85 g) 6,582 731%
Sweet potato (baked) 1 medium 1,403 156%
Spinach (cooked) ½ cup 573 64%
Carrots (raw) ½ cup 459 51%
Cantaloupe ½ cup 135 15%
Red bell pepper ½ cup 117 13%
Mango 1 cup 89 10%
Eggs 1 large 75 8%

Data sourced from USDA FoodData Central [6].

Vitamin D: Functions and Food Sources

Vitamin D is often called the "sunshine vitamin" because your skin produces it when exposed to ultraviolet B (UVB) radiation. Despite this, studies indicate that approximately 42% of American adults have insufficient vitamin D levels, with rates even higher among people with darker skin tones, older adults, and those living at northern latitudes [2].

Key Functions of Vitamin D

Top Food Sources of Vitamin D

Food Serving Size Vitamin D (mcg) % Daily Value
Cod liver oil 1 tbsp 34.0 170%
Trout (cooked) 3 oz 16.2 81%
Salmon (sockeye, cooked) 3 oz 14.2 71%
Mushrooms (UV-exposed) ½ cup 9.2 46%
Fortified milk 1 cup 2.9 15%
Sardines (canned) 2 sardines 1.2 6%
Egg yolk 1 large 1.1 6%
Fortified orange juice 1 cup 2.5 13%

Data sourced from NIH Office of Dietary Supplements [2].

Track this plan in Nutrition.io — Log your vitamin A, D and E intake daily and get AI-powered insights into your micronutrient gaps. Download on the App Store

Vitamin E: Functions and Food Sources

Vitamin E refers to a group of eight compounds — four tocopherols and four tocotrienols — with alpha-tocopherol being the most biologically active form in humans [3].

Key Functions of Vitamin E

Top Food Sources of Vitamin E

Food Serving Size Vitamin E (mg) % Daily Value
Sunflower seeds 1 oz 7.4 49%
Almonds 1 oz 7.3 49%
Sunflower oil 1 tbsp 5.6 37%
Hazelnuts 1 oz 4.3 29%
Peanut butter 2 tbsp 2.9 19%
Spinach (cooked) ½ cup 1.9 13%
Broccoli (cooked) ½ cup 1.2 8%
Kiwi 1 medium 1.1 7%

Data sourced from NIH Office of Dietary Supplements [3].

Daily Requirements by Age

The recommended dietary allowances (RDAs) for vitamin A, D and E vary by age, sex, and life stage. The following table summarizes the current guidelines from the National Institutes of Health [1][2][3]:

Age Group Vitamin A (mcg RAE/day) Vitamin D (mcg/day) Vitamin E (mg/day)
Infants 0–6 months 400* 10* 4*
Infants 7–12 months 500* 10* 5*
Children 1–3 years 300 15 6
Children 4–8 years 400 15 7
Children 9–13 years 600 15 11
Males 14–18 years 900 15 15
Females 14–18 years 700 15 15
Adult males 19–70 900 15 15
Adult females 19–70 700 15 15
Adults 71+ years 700–900 20 15
Pregnant women 770 15 15
Breastfeeding women 1,300 15 19

*Adequate Intake (AI) values when RDA has not been established.

Understanding your specific requirements is crucial for building an effective nutrition plan. Your blood work results can reveal whether you're meeting these targets or falling short.

Deficiency Signs and Symptoms

Recognizing deficiency early can prevent serious health consequences. Here's what to watch for with each vitamin:

Vitamin A Deficiency Signs

Vitamin D Deficiency Signs

Vitamin E Deficiency Signs

Vitamin E deficiency is relatively rare in healthy individuals but may occur with fat malabsorption conditions [3]:

If you notice any of these symptoms, a comprehensive blood work nutrition analysis can help confirm whether vitamin levels are a contributing factor. Learn more about interpreting your results in our guide to the best vitamins for energy.

7-Day Meal Plan for Optimal Vitamin A, D and E Intake

This sample meal plan is designed to meet daily requirements for all three fat-soluble vitamins through whole foods. Track this plan in Nutrition.io for personalized adjustments.

Day 1

Day 2

Day 3

Day 4

Day 5

Day 6

Day 7

How to Track Your Vitamin Intake

Accurately monitoring your intake of vitamin A, D and E requires more than guesswork. Here are evidence-based strategies:

  1. Use a nutrition tracking app: Tools like Nutrition.io can automatically calculate your micronutrient intake from logged meals and flag potential gaps in vitamin A, D and E
  2. Get regular blood work: Serum retinol, 25-hydroxyvitamin D, and alpha-tocopherol levels provide the most accurate assessment of your status. Learn how to interpret these in our blood work analysis guide
  3. Focus on food variety: Eating a diverse range of colorful vegetables, healthy fats, and quality proteins naturally covers most micronutrient bases
  4. Consider seasonal adjustments: Vitamin D synthesis drops dramatically in winter months at latitudes above 37°N. You may need to increase food sources or discuss supplementation with your healthcare provider [2]
  5. Track alongside your metabolic profile: Understanding how vitamin A, D and E fit into your broader metabolic profile helps you make more informed decisions

Understanding clinical nutrition principles can also help you contextualize your vitamin intake within a broader health strategy.

Frequently Asked Questions

What is the difference between vitamin A, D and E?

Vitamin A primarily supports vision and immune function, vitamin D regulates calcium metabolism and bone health, and vitamin E serves as the body's primary fat-soluble antioxidant. All three are fat-soluble vitamins that require dietary fat for absorption, but they serve distinct biological roles [1][2][3].

Can you take vitamin A, D and E together?

Yes, research suggests that taking vitamin A, D and E together is generally safe and may even be beneficial since they are all fat-soluble and share similar absorption pathways. However, excessive intake of any single fat-soluble vitamin can lead to toxicity, so it's important to stay within recommended daily allowances unless directed by a healthcare provider [1].

What are the signs of vitamin A, D and E deficiency?

Common signs include night blindness and dry skin (vitamin A), bone pain and fatigue (vitamin D), and peripheral neuropathy and muscle weakness (vitamin E). A comprehensive blood panel is the most reliable way to identify deficiencies [2][3].

Which foods are highest in vitamin A, D and E?

Beef liver and sweet potatoes lead for vitamin A, fatty fish like salmon and trout are top sources of vitamin D, and sunflower seeds and almonds are the richest in vitamin E. Eating a varied diet that includes all three food groups is the best approach [6].

How much vitamin A, D and E do adults need daily?

Adult men need 900 mcg RAE of vitamin A, 15 mcg of vitamin D, and 15 mg of vitamin E daily. Adult women need 700 mcg RAE of vitamin A, with the same vitamin D and E requirements. These values may increase during pregnancy and breastfeeding [1][2][3].


Sources

  1. National Institutes of Health. "Vitamin A — Fact Sheet for Health Professionals." NIH Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/
  2. National Institutes of Health. "Vitamin D — Fact Sheet for Health Professionals." NIH Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
  3. National Institutes of Health. "Vitamin E — Fact Sheet for Health Professionals." NIH Office of Dietary Supplements. https://ods.od.nih.gov/factsheets/VitaminE-HealthProfessional/
  4. Mawson AR, Croft AM. "Interactions between vitamin A and vitamin D." Nutrition Reviews. 2019;77(6):466-479. doi:10.1093/nutrit/nuz006
  5. Huang Z, Liu Y, Qi G, et al. "Role of Vitamin A in the Immune System." J Clin Med. 2018;7(9):258. doi:10.3390/jcm7090258
  6. U.S. Department of Agriculture. "FoodData Central." USDA. https://fdc.nal.usda.gov/
  7. Aranow C. "Vitamin D and the immune system." J Investig Med. 2011;59(6):881-886. doi:10.2310/JIM.0b013e31821b8755
  8. Lewis ED, Meydani SN, Wu D. "Regulatory role of vitamin E in the immune system and inflammation." IUBMB Life. 2019;71(4):487-494. doi:10.1002/iub.1976

About the Author

Sarah Chen, RD is a registered dietitian specializing in micronutrient optimization and clinical nutrition. She has over 8 years of experience helping clients use evidence-based nutrition strategies to address vitamin deficiencies and improve metabolic health.

Reviewed by Dr. James Patel, MS, RDN — a nutrition scientist with a focus on fat-soluble vitamin metabolism and public health nutrition research.


This content is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.