Best Foods to Boost Vitamin D Levels

Maintaining adequate levels of vitamin D is essential for the absorption of calcium, which supports the health of bones, teeth, and muscles. While the body produces most of its vitamin D when the skin is exposed to daylight, dietary intake serves as a critical secondary source, particularly for those with limited sun exposure or specific dietary restrictions.

The recommended daily intake of vitamin D is approximately 10 micrograms, which is equivalent to 400 international units (IU). In some regions, such as the UK, it is estimated that 1 in 6 adults have low blood levels of the vitamin, increasing the risk of deficiency.

Primary Dietary Sources of Vitamin D

Oily and fatty fish are among the most potent natural sources of vitamin D. Different species and origins can significantly impact the amount of the vitamin provided per serving.

• Salmon: Farmed Atlantic salmon provides approximately 441 IU per 100-gram serving. Wild-caught salmon often contains higher levels; for example, salmon caught in the Baltic Sea can provide between 556 and 924 IU per 100 grams.
• Herring: Fresh Atlantic herring offers around 167 IU per 100-gram serving, while grilled herring is noted to contain 16.1 micrograms per 100 grams.
• Mackerel: This fish provides 643 IU per 100-gram serving, or 8.5 micrograms per 100 grams when grilled.
• Sardines: Canned sardines in brine provide approximately 3.3 micrograms per 100 grams.
• Halibut: This fatty fish provides 190 IU per 100-gram serving.

Plant-Based and Fortified Alternatives

Because relatively few foods naturally contain high amounts of vitamin D, many products are fortified to help the general population, including vegetarians, vegans, and individuals with food allergies, meet their nutritional needs.

Fortified foods that serve as reliable sources include cow’s milk, soy milk, and orange juice. These additions are designed to help maintain overall health and bone strength.

Among non-fortified, non-fish options, eggs and mushrooms contribute to vitamin D levels. Mushrooms are particularly effective when they have been exposed to UV light.

The Role of Sunlight and Supplementation

Dietary intake alone is often insufficient to meet daily requirements. In the UK, the average intake from food is estimated to be only 2 to 3 micrograms per day, well below the recommended 10 micrograms.

From late March to the end of September, a combination of a balanced diet and sunlight is typically sufficient for most people. However, during the months of October through March, sunlight is less available, and the UK government recommends taking vitamin D supplements.

Certain populations may require supplements year-round, including individuals who do not spend much time outdoors or those who cover their skin while outside.

Healthcare providers, including dietitians and nutritionists, suggest that individuals consult their medical team to determine how specific food choices and supplements should be integrated into their personal health plans to maintain optimal vitamin D levels.