Maximizing Your Intake: How can I get a large amount of vitamin D?

November 10, 2025 •

4 min read

An estimated 35% of American adults and 50% of the global population have a vitamin D deficiency. To address this widespread issue, understanding how can I get a large amount of vitamin D is essential for maintaining strong bones and supporting overall health through a combination of diet, safe sun exposure, and supplementation.

Quick Summary

This guide covers the most effective strategies for significantly increasing your vitamin D intake, focusing on key dietary sources, fortified foods, the strategic use of supplements, and responsible sun exposure. It provides a practical overview of how to boost your levels to prevent deficiency and its related health issues.

Key Points

Supplements for Efficiency: For a potentially more rapid increase, dietary supplements (preferably D3) can be an effective method, especially for addressing a diagnosed deficiency.
Fatty Fish and Cod Liver Oil: Fatty fish and cod liver oil are among the richest natural food sources of vitamin D, providing varying amounts per serving.
Safe Sun Exposure: Moderate midday sun exposure on bare skin triggers natural vitamin D synthesis, but duration and frequency must be balanced with skin cancer risk.
Fortified Foods Boost Intake: Regularly consuming fortified foods like milk, cereals, and orange juice can provide a consistent source of vitamin D.
UV-Treated Mushrooms: Look for UV-exposed mushrooms in stores, as this treatment can increase their vitamin D2 content, providing a plant-based option.
Consult a Professional: Due to individual needs and potential risks, it's best to consult a healthcare provider for blood testing and guidance.

The Power Trio: Supplements, Sun, and Diet

For many, relying on a single method to achieve optimal vitamin D levels is insufficient. A multi-pronged approach that includes dietary supplements, strategic sunlight exposure, and vitamin-rich foods is the most effective strategy. The fastest and most targeted method for increasing vitamin D, especially for those with a confirmed deficiency, is supplementation under medical guidance.

Maximize Intake with Dietary Supplements

For those seeking a significant and rapid increase, supplements can be an efficient route, particularly when recommended by a healthcare provider.

Vitamin D3 vs. D2: The two primary forms found in supplements are D3 (cholecalciferol) and D2 (ergocalciferol). Research indicates that vitamin D3 is generally more effective at raising and maintaining higher blood vitamin D levels over time.
Optimal Absorption: Since vitamin D is fat-soluble, taking supplements with a meal or snack containing fat can significantly improve its absorption and utilization by the body.
Supplementation for Deficiency: For cases of deficiency, a healthcare provider may recommend a specific regimen to restore levels effectively.
Maintaining Levels: Once levels are within a desirable range, a maintenance approach is often recommended. It is important to follow medical guidance regarding intake amounts due to the potential for excessive intake.

Harnessing Safe Sunlight Exposure

Your body can produce its own vitamin D from cholesterol when your bare skin is exposed to UVB rays from the sun. While this is a natural source, it's not always reliable and requires a balanced approach to avoid skin cancer risks.

Midday is Best: The sun's UVB rays are most intense around midday. Moderate, unprotected exposure for a limited time, a few times per week, during this time is often sufficient for many people to produce some vitamin D during warmer months.
Factors Affecting Production: Several factors influence how much vitamin D your skin can produce. People with darker skin have more melanin, which acts as a natural sunscreen, and therefore require longer sun exposure than those with lighter skin. Geographical location also plays a role; individuals far from the equator produce less vitamin D during winter months.
Safety First: The American Academy of Dermatology advises against using sun exposure as a primary source of vitamin D due to skin cancer risks and recommends relying on food and supplements instead. When spending extended time outdoors, use sunscreen after a short initial period of unprotected exposure.

Incorporating Vitamin D-Rich Foods

While difficult to get a very large amount from diet alone, certain foods and fortified products can provide a substantial boost, especially when combined with other methods. For those with dietary restrictions, such as vegans, options exist through fortified products and specially prepared mushrooms.

Fatty Fish and Fish Oils: Fatty fish like salmon, sardines, mackerel, and trout are among the best natural sources of vitamin D. Cod liver oil is also a notable source.
UV-Treated Mushrooms: Similar to humans, mushrooms can synthesize vitamin D2 when exposed to UV light. Many commercially grown mushrooms are now intentionally exposed to UV light to significantly boost their vitamin D content. Check the label for this designation.
Fortified Foods: Many staple foods are fortified with vitamin D to help consumers meet their daily needs. Common examples include cow's milk and plant-based alternatives (soy, almond, oat), certain orange juices, and ready-to-eat breakfast cereals.
Other Animal Sources: Smaller amounts of vitamin D can be found in egg yolks, beef liver, and cheese.

Comparison of High-Vitamin D Food Sources

To put the food sources into perspective, here is a comparison table based on typical portion sizes and estimated content:


Food Source	Serving Size	Estimated Vitamin D (IU)	Notes
Cod Liver Oil	1 tablespoon	1,360	Also high in Vitamin A; not recommended for high intake during pregnancy.
Wild Sockeye Salmon	3 ounces (cooked)	570	Excellent natural source, content varies by species.
UV-Treated Mushrooms	1/2 cup (sliced)	366	A powerful plant-based option for those exposed to UV light.
Canned Light Tuna	3 ounces (drained)	40	Contains mercury; moderate consumption is advised.
Fortified Milk (2%)	1 cup	120	A common fortified staple in many diets.
Egg Yolk	1 large (scrambled)	44	A modest but reliable dietary source.

Important Considerations

Several factors can affect vitamin D absorption and requirements, highlighting the need for a personalized approach.

Body Weight: People with obesity may have lower circulating levels of vitamin D, as the fat tissue can sequester it, and may require different approaches to achieve sufficient blood levels.
Malabsorption Conditions: Conditions such as Crohn's disease, celiac disease, and ulcerative colitis can impair fat absorption, and consequently, the absorption of fat-soluble vitamin D.
Age: The body's ability to synthesize vitamin D from sunlight declines with age, making supplements and dietary sources even more critical for older adults.
Medications: Certain medications can interfere with vitamin D absorption or metabolism. It is important to discuss any concerns with a healthcare provider.

Conclusion

For individuals with a significant deficiency or those looking to achieve a large amount of vitamin D, the most effective path involves a combination of strategies tailored to their unique needs. While diet offers reliable, incremental benefits, supplements and safe sun exposure are the most direct routes to increasing vitamin D levels. Consulting with a healthcare provider for a blood test and personalized recommendations is the safest way to address a deficiency and maintain optimal levels. Integrating high-vitamin D foods like fatty fish and fortified dairy, along with controlled sun exposure, provides a sustainable approach to long-term health.

NIH provides further in-depth information and dietary reference values for health professionals.

Frequently Asked Questions

The fastest way to get a large amount of vitamin D is typically through a supplement, especially when treating a diagnosed deficiency. A healthcare provider can recommend an appropriate approach to quickly raise blood levels.

It is often difficult to get a large amount of vitamin D from food alone, as few foods are naturally rich in it. However, combining fatty fish, fortified dairy, and UV-treated mushrooms with other strategies can help meet your needs.

People with darker skin have more melanin, which reduces the skin's ability to produce vitamin D from sunlight. They may require longer sun exposure than people with lighter skin to produce the same amount.

For a boost from food, good options include cod liver oil, wild-caught salmon, trout, and UV-treated mushrooms. Fortified milk and cereals also contribute consistently.

Vitamin D supplements are generally safe when taken as recommended by a healthcare provider. However, consuming excessive amounts without medical guidance can potentially lead to issues.

The only reliable way to know your vitamin D status is through a blood test that measures 25-hydroxyvitamin D levels. Symptoms of a significant deficiency can include fatigue, bone pain, muscle weakness, and frequent illness.

For many, moderate unprotected midday sun exposure on the face, arms, and legs a few times per week may contribute to vitamin D production during sunny seasons. However, this varies based on skin tone, latitude, and season, and should be balanced with skin cancer prevention.