Vitamin A and D Foods: The Best Natural Sources to Boost Your Health

What Does Vitamin A Do?

Vitamin A is a fat-soluble vitamin that performs numerous essential functions throughout your body, making it absolutely critical for maintaining health from head to toe. This versatile nutrient influences multiple systems simultaneously, and deficiency can create cascading health problems.

Key functions of vitamin A include:

• Eye health and vision: Vitamin A is essential for producing rhodopsin, a protein in your eyes that enables you to see in low-light conditions. It helps prevent night blindness and supports overall visual function. The retina requires constant vitamin A supply to function properly
• Immune system support: This vitamin helps maintain the integrity of mucous membranes in your respiratory, digestive, and urinary tracts, serving as your body's first line of defense against pathogens. It also supports the development and function of white blood cells that fight infections
• Skin and tissue health: Vitamin A promotes healthy skin cell production and turnover, keeping your skin smooth and helping wounds heal properly. It maintains the health of all epithelial tissues throughout your body
• Reproduction and fetal development: Adequate vitamin A is crucial for reproductive health in both men and women. During pregnancy, it supports proper fetal development, particularly of the heart, lungs, kidneys, eyes, and bones
• Gene expression: Vitamin A influences which genes are turned on or off in your cells, affecting growth, development, and cellular differentiation

Understanding the two types of vitamin A:

Preformed vitamin A (retinol) is the active form found in animal products like liver, fish, eggs, and dairy. Your body can use this form immediately without conversion, making it highly bioavailable and efficient.

Provitamin A carotenoids (primarily beta-carotene) are found in colorful fruits and vegetables like carrots, sweet potatoes, spinach, and red peppers. Your body must convert these plant compounds into active vitamin A, and conversion efficiency varies significantly between individuals. Generally, you need to consume about 12 micrograms of beta-carotene to produce 1 microgram of retinol.

What About Vitamin D?

Vitamin D, often called the "sunshine vitamin" because your skin produces it when exposed to sunlight, is another fat-soluble nutrient with profound impacts on multiple body systems. While traditionally recognized for bone health, research continues revealing additional critical roles.

Essential functions of vitamin D include:

• Calcium and phosphorus absorption: Vitamin D is absolutely necessary for your intestines to absorb calcium and phosphorus from food efficiently. Without adequate vitamin D, you cannot maintain healthy bones regardless of calcium intake
• Bone health and strength: By facilitating calcium absorption and regulating calcium levels in blood, vitamin D prevents bone softening diseases like rickets in children and osteomalacia in adults, and reduces osteoporosis risk
• Muscle function: Adequate vitamin D supports muscle strength and coordination, reducing fall risk in older adults. Deficiency is associated with muscle weakness and pain
• Immune system regulation: Vitamin D modulates both innate and adaptive immune responses, helping your body fight infections while preventing excessive inflammation and autoimmune reactions
• Mood and mental health: Receptors for vitamin D exist throughout the brain, and the vitamin influences neurotransmitter production. Low levels are associated with increased risk of depression and seasonal affective disorder
• Cardiovascular health: Vitamin D helps regulate blood pressure and may reduce heart disease risk through multiple mechanisms

The two forms of vitamin D:

Vitamin D2 (ergocalciferol) comes from plant sources, particularly mushrooms exposed to UV light, and fortified foods. While effective, it is generally less potent and shorter-acting than D3.

Vitamin D3 (cholecalciferol) is found in animal-based foods like fatty fish, egg yolks, and liver, and is the form your skin produces from sunlight. D3 is more effective at raising and maintaining blood levels of vitamin D compared to D2.

Animal-Based Vitamin D Foods

• Fatty fish (the champions):
  • Salmon (wild-caught): 3 ounces provides 570 IU (14 mcg) - 95% DV
  • Mackerel: 3 ounces contains 360 IU (9 mcg) - 60% DV
  • Sardines: 2 sardines offer 46 IU (1.2 mcg) - 8% DV
  • Trout: 3 ounces provides 645 IU (16 mcg) - 108% DV
  • Tuna (canned): 3 ounces contains 40 IU (1 mcg) - 7% DV
• Cod liver oil: 1 tablespoon delivers 1,360 IU (34 mcg) - 227% DV, making it one of the most concentrated sources
• Egg yolks: One large egg provides 44 IU (1.1 mcg) - 7% DV. Eggs from chickens given vitamin D-enriched feed contain much more
• Beef liver: 3 ounces offers 42 IU (1 mcg) - 7% DV plus vitamin A
• Fortified dairy products: 1 cup fortified milk contains 115-120 IU (3 mcg) - 19-20% DV. Check labels as fortification varies

👉 Wild Alaskan Canned Salmon 👉 Sardines in Olive Oil

Plant-Based and Fortified Vitamin D Options

• UV-exposed mushrooms: Mushrooms treated with UV light can provide significant vitamin D2. Portobello mushrooms exposed to UV light may contain 400-800 IU per 3-ounce serving. Regular mushrooms without UV treatment contain minimal vitamin D
• Fortified plant milks: Almond, soy, oat, and other plant milks are often fortified with 100-120 IU per cup. Always check labels as fortification is not universal
• Fortified orange juice: Some brands provide 100 IU per cup
• Fortified cereals and oatmeal: Many breakfast cereals are fortified with 40-100 IU per serving. Check nutrition labels
• Fortified tofu: Some brands fortify tofu with vitamin D, providing 80-120 IU per serving

👉 Vitamin D Mushrooms - Sun-Dried Organic 👉 Califia Farms Almond Milk - Fortified

Vitamin A Deficiency Symptoms

Vitamin A deficiency is relatively rare in developed countries but can occur in people with absorption disorders, restrictive diets, or certain health conditions. Watch for these warning signs:

• Night blindness (nyctalopia): Difficulty seeing in dim light or darkness is often the earliest sign of vitamin A deficiency. Your eyes need vitamin A to adjust between bright and low light conditions
• Dry eyes (xerophthalmia): Inadequate tear production leading to dry, irritated eyes. In severe cases, this can progress to corneal damage and blindness
• Dry, rough, or scaly skin: Vitamin A deficiency disrupts normal skin cell production, leading to thickened, dry patches particularly on arms and thighs
• Acne and skin problems: Vitamin A regulates oil production and cell turnover; deficiency can worsen acne and other skin conditions
• Frequent infections: Weakened immune function makes you more susceptible to respiratory, urinary, and other infections
• Poor wound healing: Cuts and scrapes take longer to heal properly
• Reproductive problems: Difficulty conceiving or maintaining pregnancy
• Delayed growth in children: Inadequate vitamin A impairs normal growth and development

If you experience several of these symptoms, particularly night blindness or frequent infections, request vitamin A testing from your healthcare provider. Blood tests can measure retinol levels and assess your status accurately.

Vitamin D Deficiency Symptoms

Vitamin D deficiency is extremely common, affecting an estimated 1 billion people worldwide. Many people have inadequate levels without realizing it because symptoms can be vague and develop gradually.

• Bone pain and tenderness: Aching bones, particularly in the back, hips, and legs, may indicate insufficient vitamin D for proper calcium metabolism
• Muscle weakness and pain: Difficulty climbing stairs, getting up from seated positions, or unexplained muscle aches throughout the body
• Chronic fatigue and low energy: Persistent tiredness that does not improve with rest
• Frequent illness or infections: Getting sick often, particularly respiratory infections like colds and flu
• Depression and mood changes: Low mood, seasonal affective disorder, or clinical depression may be linked to inadequate vitamin D
• Impaired wound healing: Slow recovery from injuries or surgical procedures
• Bone loss and fractures: Reduced bone density (osteopenia or osteoporosis) and increased fracture risk
• Hair loss: Thinning hair or excessive shedding may indicate deficiency
• Cognitive impairment: Difficulty concentrating, memory problems, or brain fog

Because vitamin D deficiency is so prevalent and symptoms overlap with many conditions, testing is worthwhile for most people. The 25-hydroxy vitamin D blood test measures your status accurately. Optimal levels are generally considered 30-60 ng/mL (75-150 nmol/L), though some experts recommend 40-60 ng/mL for best health outcomes.

NOW Supplements Vitamin A 10,000 IU from Fish Liver Oil: This supplement provides preformed vitamin A in a dose suitable for addressing deficiency under medical supervision. The 10,000 IU dose equals the tolerable upper limit, so use only as directed by a healthcare provider. Best for those with documented deficiency or severe absorption issues.

👉 NOW Supplements Vitamin A 10,000 IU

NatureWise Vitamin D3 5,000 IU (125 mcg): This highly-rated vitamin D3 supplement provides an optimal dose for correcting deficiency or maintaining healthy levels. The 5,000 IU dose is safe for daily use for most adults and more effective than lower doses at raising blood levels. Non-GMO and gluten-free.

👉 NatureWise Vitamin D3 5,000 IU

Carlson Cod Liver Oil - Vitamin A and D Combination: This traditional supplement provides both vitamins A and D in their natural forms from cod liver oil, along with beneficial omega-3 fatty acids. One teaspoon delivers approximately 850 IU vitamin A and 400 IU vitamin D. Excellent quality with lemon flavor to mask fish taste.

👉 Carlson Cod Liver Oil - A+D Combo