From the Guidelines
To improve vitamin D absorption, adults should take vitamin D supplements, typically 600-800 IU daily, preferably with a meal containing some fat to enhance absorption, as recommended by the Institute of Medicine 1.
Key Strategies for Improvement
- Consume vitamin D-rich foods like fatty fish (salmon, mackerel), egg yolks, and fortified products (milk, orange juice, cereals) to support overall vitamin D intake.
- Spend 10-30 minutes in sunlight several times weekly, as UVB rays trigger vitamin D production in the skin, but be cautious of the risk of skin cancer associated with UVB radiation 1.
- Consider taking vitamin D with magnesium supplements, as magnesium helps activate vitamin D in the body.
- Reduce alcohol consumption and quit smoking, as these habits can interfere with vitamin D metabolism.
- Maintain a healthy weight since excess body fat can trap vitamin D and prevent it from circulating in the bloodstream.
- If you have digestive issues like Crohn's disease or celiac disease, work with your healthcare provider to manage these conditions, as they can impair nutrient absorption, and consider vitamin D supplementation to reduce the risk of bone disease 1.
Importance of Vitamin D
Vitamin D is essential for bone health, immune function, and overall wellbeing. Its deficiency has been associated with various health issues, including increased risk of falls, fractures, and cardiovascular disease. Therefore, ensuring adequate vitamin D levels through a combination of dietary intake, sunlight exposure, and supplementation is crucial for maintaining good health.
Special Considerations
For individuals with inflammatory bowel disease (IBD), such as Crohn's disease or ulcerative colitis, vitamin D deficiency is common and can exacerbate disease activity and bone health issues 1. In such cases, routine measurement of vitamin D status and correction of deficiency using oral supplementation are recommended. However, the impact of vitamin D on inflammation in IBD and its optimal level as a treatment goal are not yet fully understood and require further research.
From the Research
Improving Vitamin D Absorption
To improve vitamin D absorption, several factors should be considered:
- Taking vitamin D with the largest meal of the day can enhance absorption and result in higher serum levels of 25-hydroxyvitamin D 2
- Consuming vitamin D with a meal containing fat can increase absorption, as fat increases vitamin D-3 absorption 3, 4
- The type of fat in the meal may not significantly influence vitamin D absorption, as studies have shown no difference in absorption between meals with high and low monounsaturated-to-polyunsaturated fatty acid ratios 3
Factors Affecting Vitamin D Absorption
Several factors can affect vitamin D absorption, including:
- Dietary composition, with fat-containing meals enhancing absorption 3, 2, 4
- The presence of other nutrients, such as cholesterol, which can modify vitamin D absorption 4
- Individual factors, such as genetic variants in vitamin D hydroxylation and transport, which can contribute to vitamin D deficiency 5, 6
Optimal Vitamin D Levels
The optimal levels of vitamin D required for non-skeletal effects, such as immune function and disease prevention, are not yet fully established: