Foods That Increase 25-Hydroxyvitamin D Levels Naturally

January 5, 2026 •

4 min read

Worldwide, over one billion people are estimated to have vitamin D deficiency, making it a critical public health issue. While sunlight is a primary source, many foods can significantly contribute to maintaining or increasing your levels of 25-hydroxyvitamin D, the main circulating form of the vitamin in your body.

Quick Summary

An overview of dietary options, including fatty fish, fortified products, and certain fungi, to boost your 25-hydroxyvitamin D levels. Explains the difference between natural and fortified sources for effective dietary planning. Provides practical food examples and preparation methods for increasing your intake.

Key Points

Fatty Fish is Key: Oily fish like salmon, sardines, and mackerel are among the most powerful natural dietary sources of vitamin D3, which is efficiently used by the body.
Fortified Foods Bridge the Gap: Many foods, including milk, cereal, and orange juice, are fortified with vitamin D to help meet daily needs, especially for those with limited natural sources.
Mushrooms are a Plant-Based Source: Certain mushrooms, when exposed to ultraviolet (UV) light, produce vitamin D2 and can be a good option for vegetarians and vegans.
Fat Enhances Absorption: Since vitamin D is fat-soluble, consuming it with healthy fats can increase its absorption into the body.
Dietary Intake May Not Be Enough: While diet is important, it may not be sufficient to correct a significant deficiency, which often requires medical supervision and supplementation.
Cod Liver Oil is a Potent Option: Cod liver oil is a highly concentrated source of vitamin D, though careful dosage is necessary due to its high vitamin A content.

Understanding 25-Hydroxyvitamin D and Your Diet

25-hydroxyvitamin D (25(OH)D) is the storage form of vitamin D, and its measurement in the blood is the best indicator of overall vitamin D status. While our bodies can synthesize vitamin D from sunlight, dietary sources play a crucial role, especially during seasons with limited sun exposure or for individuals with limited outdoor time. Unlike a simple pill, obtaining vitamin D through food provides a range of other essential nutrients and helps create a balanced diet. Incorporating specific foods rich in either vitamin D2 or D3 can be a powerful strategy for maintaining adequate levels.

The Top Food Sources for Increasing Vitamin D

Natural Sources Rich in Vitamin D3

The most potent and bioavailable dietary source of vitamin D comes from animal products, particularly fatty fish. These foods contain vitamin D3 (cholecalciferol), which is more effectively utilized by the body to raise 25(OH)D levels compared to the plant-based vitamin D2.

Fatty Fish: Oily fish are at the top of the list for natural vitamin D content. A 3.5-ounce serving of wild-caught salmon can contain a significant portion of the recommended daily intake. Other excellent choices include:
- Wild-caught salmon and trout
- Mackerel
- Sardines and herring
- Tuna, especially canned varieties
Cod Liver Oil: This supplement is an incredibly concentrated source of vitamin D and is often used to quickly and effectively raise levels.
Egg Yolks: The yolks from eggs, particularly those from pasture-raised hens, contain a modest amount of vitamin D. The hens' diet and sun exposure influence the vitamin content of their eggs.
Beef Liver: While it contains some vitamin D, the concentration is generally lower than that of fatty fish.

Plant-Based and Fortified Sources

For those on vegetarian or vegan diets, or for anyone looking to supplement their intake, fortified foods and a specific type of fungi are key. Mushrooms produce vitamin D2 (ergocalciferol) when exposed to UV light, making them a unique plant-based source.

UV-Treated Mushrooms: The vitamin D content in mushrooms can vary dramatically. Store-bought varieties, like cremini, often contain very little vitamin D unless explicitly labelled as UV-treated. Wild mushrooms or those grown under UV light are the most reliable option.
Fortified Milk: Many milks, including cow's milk and plant-based alternatives like soy, almond, and oat milk, are fortified with vitamin D. It's essential to check the nutrition label as fortification levels can differ.
Fortified Breakfast Cereals and Orange Juice: A wide array of cereals and some brands of orange juice are fortified with vitamin D, providing a convenient way to boost your intake at breakfast.
Fortified Margarine and Spreads: In some regions, margarine and other fat spreads are legally required or voluntarily fortified with vitamin D.

Dietary Strategies to Maximize Absorption

Vitamin D is a fat-soluble vitamin, which means it requires fat to be properly absorbed by the body. Pairing your vitamin D-rich foods with healthy fats can significantly enhance absorption. For instance, enjoying grilled salmon with a drizzle of olive oil or consuming fortified yogurt with some nuts can be beneficial.

Comparison of Vitamin D Food Sources


Food Source	Type of Vitamin D	IU per serving (approx.)	Best for	Notes
Cod Liver Oil	Vitamin D3	1,360 IU per tbsp	Rapidly increasing levels	High concentration, but also contains a lot of Vitamin A, so dosage must be managed.
Wild Salmon	Vitamin D3	570-1000 IU per 3.5oz	Heart-healthy omega-3s	A complete protein source with a high vitamin D content.
UV-Treated Mushrooms	Vitamin D2	1100 IU per cup	Vegan/vegetarian diets	Must be explicitly labeled as UV-treated for a reliable source.
Fortified Cow's Milk	Vitamin D3 (typically)	120 IU per cup	Convenient daily intake	A common and easy way to add vitamin D to a diet, along with calcium.
Egg Yolk	Vitamin D3	40-50 IU per yolk	Small, regular boost	Content varies based on the hen's diet and access to sunlight.

Conclusion

While sun exposure is a major source of vitamin D, relying solely on it can be inconsistent and may carry risks, making dietary intake essential for maintaining healthy 25-hydroxyvitamin D levels. By strategically incorporating fatty fish, UV-treated mushrooms, and fortified products into your diet, you can effectively boost your vitamin D status. It's important to remember that diet alone may not be enough to correct a significant deficiency, and in such cases, supplementation under a healthcare provider's supervision may be necessary. A balanced approach combining a nutrient-rich diet with sensible sun exposure is the best way to support your overall health and well-being. For specific dietary guidance, consult a registered dietitian or your doctor.

More information from authoritative sources

For additional scientific data on vitamin D in various food sources, the NIH Office of Dietary Supplements offers comprehensive fact sheets.

Disclaimer: This article is for informational purposes only and should not be considered medical advice. Always consult with a healthcare professional before making significant changes to your diet or starting a new supplement regimen.

Frequently Asked Questions

For most people, it is challenging to obtain sufficient vitamin D from diet alone due to the limited number of naturally rich food sources. Sunlight exposure and, in some cases, supplements are often necessary to reach adequate levels.

Fortified foods can be an excellent and convenient source of vitamin D, especially for individuals with dietary restrictions or low sun exposure. However, the bioavailability and specific form of vitamin D (D2 vs. D3) can differ from natural sources like fatty fish.

Vegetarians and vegans can increase their levels through fortified plant-based milks, fortified cereals, and UV-treated mushrooms. Supplements are also a reliable option, especially for those with limited sun exposure.

Cooking methods generally have a minimal effect on the vitamin D content of foods. For instance, research suggests that cooking mushrooms in water does not significantly reduce their vitamin D, but cooking in oil may have some effect.

Vitamin D3 (cholecalciferol) comes from animal sources and is considered more effective at raising blood 25(OH)D levels. Vitamin D2 (ergocalciferol) is found in plant sources like mushrooms. Both can increase vitamin D levels, but D3 is generally more potent.

Consistency is key. Aiming to include vitamin D-rich foods regularly, such as fatty fish a couple of times a week and fortified products daily, helps maintain stable vitamin D levels over time.

Aside from UV-treated mushrooms (which are technically fungi), fruits and vegetables are not significant natural sources of vitamin D. Certain juices can be fortified, but it is not a natural property of the fruit itself.