In East Asian medicine, winter is a season of conservation and deep nourishment. As the days grow shorter and we spend more time indoors here in the Midwest, one challenge many people face is maintaining adequate vitamin D levels. This nutrient plays a foundational role in immune resilience, mood regulation, energy balance, and overall well-being.
Why vitamin D is especially important in winter
From late fall through early spring, the sun’s angle in our region is too low for the skin to produce sufficient vitamin D—even on clear, sunny days. As a result, low vitamin D levels are very common during the winter months and can quietly contribute to a range of physical and emotional symptoms.
Common signs and conditions associated with low vitamin D
When vitamin D levels are suboptimal, people often experience or notice patterns such as:
- Persistent fatigue or low energy
- Seasonal affective patterns, low mood, or depression
- Frequent colds, flu, or recurrent infections
- Eczema, dry skin, or inflammatory skin conditions
- Thyroid imbalances, including hypothyroidism
- Generalized aches, immune weakness, or difficulty maintaining vitality
Supporting vitamin D levels proactively during winter can be an important part of maintaining balance and resilience.
Optimal vitamin D lab ranges
Many integrative and functional medicine practitioners consider optimal vitamin D (25-OH vitamin D) blood levels to be between 60–80 ng/mL. It’s important to note that not all physicians use this reference range. Some labs and providers still rely on older, more conservative ranges that may classify levels as “normal” even when they are not optimal for immune or mood support.
If you’ve had vitamin D testing done, I encourage you to ask for your actual lab values rather than relying solely on whether the result was marked as “normal,” so you can better understand where your levels truly fall.
Supporting proper absorption
Vitamin D is fat-soluble, so how and when you take it matters:
- Take vitamin D3 with your largest meal of the day, especially one that includes healthy fats (olive oil, avocado, eggs, nuts, fish).
- Liquid forms are generally better absorbed than pills or tablets.
- Vitamin D3 works best when paired with vitamin K2, which helps guide calcium into bones and away from soft tissues.
- During the winter months, many adults benefit from up to 10,000 IU daily, though individual needs can vary.
A note for individuals with darker skin tones
Melanin reduces the skin’s ability to produce vitamin D from sunlight. People with darker skin tones—especially those living in northern climates—are at higher risk for deficiency and often require more consistent supplementation year-round.
Recommended supplement
One product I often recommend is Orthomolecular Liquid Vitamin D3 + K2, which offers excellent absorption and ease of dosing. It can be purchased directly through my Fullscript dispensary HERE.
In my practice, vitamin D support is viewed as one part of a larger, integrative approach that includes acupuncture, herbal medicine, nutrition, sleep, stress management, and seasonal alignment. If you have questions about vitamin D, lab testing, or how this fits into your individualized care plan, feel free to reach out or bring it up at your next visit.
Wishing you a well-supported and healthy winter,
Cindy Kudelka LAc, MSTOM
