I recently took a trip to Vancouver Island at the tail end of summer, and my friend and I were fortunate to experience two beautiful, sunny days. We made the most of them with visits to the enchanting Butchart Gardens, afternoon tea, and a sprawling, picturesque winery. Unfortunately, the rest of our trip was marked by rainy, gloomy weather.
While the island’s lush forests and thriving greenery owe much to this rainfall, days without sunshine can certainly affect how we feel. As someone who thrives on a daily dose of sunlight, I notice that prolonged stretches of cloudy weather can leave me feeling less energetic and cheerful.
And as the days grow shorter in winter, sunlight can become harder to come by. That’s when I pay a little more attention to getting enough Vitamin D through food and, when needed, supplements.
Why Is Vitamin D Important?
Vitamin D is a fat-soluble vitamin that plays an essential role in bone health, muscle function and immunity. It helps the body absorb calcium and maintain healthy levels of calcium and phosphorus—two minerals that are particularly important for building and maintaining strong bones.
Vitamin D also plays a role in immune function, and receptors for Vitamin D are found throughout the body, including in the brain.
Our bodies can produce Vitamin D3 naturally when UVB rays from sunlight reach the skin. How much we produce, however, varies considerably depending on the season, time of day, cloud cover, skin pigmentation, age, location and how much skin is exposed.
During winter, particularly in northern climates, getting enough Vitamin D from sunlight can therefore become more challenging.
Vitamin D is crucial for bone health, but it also boosts immunity and mood.
The Best Food Sources of Vitamin D
Very few foods naturally contain significant amounts of Vitamin D, which makes choosing the right sources especially important.
Fatty fish such as salmon, trout, tuna and mackerel are among the best natural sources. Smaller amounts can be found in egg yolks, beef liver and cheese, while mushrooms can provide Vitamin D2—particularly varieties that have been exposed to UV light.
Many foods, including certain milks, plant-based milks and breakfast cereals, are also fortified with Vitamin D, making them another convenient way to increase your intake.
Because Vitamin D is fat-soluble, consuming it as part of a meal that contains some healthy fat can also help with absorption.
Vitamin D Deficiency: What to Look For
Low Vitamin D levels don't always cause obvious symptoms. When deficiency becomes more pronounced, however, it may contribute to muscle weakness, bone pain and an increased risk of fractures.
If you have limited sun exposure or are concerned about your Vitamin D status, a simple blood test measuring 25-hydroxyvitamin D [25(OH)D] can help determine your levels.
What About Vitamin D and Mood?
The relationship between Vitamin D and mood is particularly interesting, although the science is more nuanced than you might think.
Research has found an association between low Vitamin D levels and depression, and Vitamin D receptors are present in areas of the brain involved in mood and brain function. However, an association doesn't necessarily mean that low Vitamin D causes depression.
Studies examining Vitamin D supplements for improving depressive symptoms have produced mixed results. So while maintaining healthy Vitamin D levels is important for overall health, Vitamin D shouldn't be thought of as a treatment for depression.
Still, if your Vitamin D levels are low—particularly during the darker winter months—bringing them back into a healthy range is one piece of supporting your overall well-being.
How to Get Enough Vitamin D in Winter
Sunlight remains an important natural source of Vitamin D, but there isn't a single amount of sun exposure that works for everyone. Season, latitude, skin tone, age and weather can all influence how efficiently your skin produces it.
It's also important to balance Vitamin D production with skin protection, since UV radiation increases the risk of skin damage and skin cancer.
During periods when sun exposure is limited, Vitamin D-rich foods, fortified foods and, when appropriate, a Vitamin D supplement can help you maintain an adequate intake.
If you're considering supplementation, particularly at higher doses, it's worth checking your Vitamin D levels and discussing the appropriate amount with your healthcare provider.
A Little Extra Support
For those looking for additional support around their menstrual cycle, Semaine PMS & Period Support contains Vitamin D3 alongside magnesium and plant extracts including ashwagandha, curcumin, quercetin and resveratrol.
The formula is designed specifically to support common PMS and period symptoms, including changes in mood, energy, bloating and discomfort. Rather than using it as a substitute for a dedicated Vitamin D supplement, I like to think of it as another way to incorporate Vitamin D into a broader wellness routine.
As winter approaches, paying a little more attention to your Vitamin D intake—through food, sensible sun exposure and supplements when needed—can be a simple way to support your bones, muscles and immune system throughout the darker months.
