By Samara Foisy, Registered Dietitian

• Declining estrogen weakens calcium absorption and accelerates bone loss after 40.
• Multiple large studies found vitamin D doesn't meaningfully improve mood, hot flashes, or brain fog.
• Vitamin D does have strong evidence for bone health and is part of Canada's current osteoporosis guidelines.
• A systematic review found vitamin D supplementation improved grip strength in postmenopausal women.

Many Canadians don't get enough, especially in fall and winter. Talk to your healthcare provider about your needs

When you're talking with your girlfriends about menopause, the conversation usually centres around hot flashes, brain fog, and sleep disruptions. We rarely talk about the less obvious changes: not feeling as strong, noticing that recovery takes longer than it used to, or finding that everyday tasks require a little more effort.

These shifts may not get as much attention, but they matter just as much. While protein tends to be the nutrient in the spotlight, vitamin D plays an equally important supporting role. It's essential for maintaining strong bones, supporting muscle function, and helping you stay strong and active. While hot flashes often improve over time, bone and muscle loss can continue unless you actively support them.

Here's the part many women don't hear about. Estrogen plays an important role in helping your body absorb calcium and maintain healthy bone turnover. As estrogen levels decline during perimenopause and menopause, that protective effect weakens, accelerating bone loss and increasing the risk of osteoporosis.

Vitamin D is a key part of this process because it helps your body absorb calcium from the foods you eat. Without enough vitamin D, even a calcium-rich diet can't do its job effectively. Calcium, vitamin D, and estrogen each play an essential role in maintaining bone health, making it especially important to maintain adequate vitamin D levels so your body can absorb and use calcium effectively.

On top of that, a lot of us in Canada are simply not getting enough. Health Canada's own data shows adults get less sun exposure than we assume for a good chunk of the year, and vitamin D isn't abundant in many everyday foods.⁵

This is where I'll be straight with you: vitamin D is not a miracle cure. Multiple large studies have found it doesn't meaningfully improve mood, hot flashes, or brain fog, despite what wellness Instagram might imply.³ If someone's selling you on that, be skeptical.

Where vitamin D does have strong scientific support is bone health. Adequate vitamin D helps your body absorb calcium, supports bone mineral density, and is an important part of maintaining healthy bones during and after menopause. Current Canadian osteoporosis guidelines recommend vitamin D as one component of a comprehensive bone health strategy, alongside adequate calcium intake and regular weight-bearing and resistance exercise.¹

Vitamin D also plays an important role in muscle function. Research suggests that maintaining adequate vitamin D levels may help support muscle strength, and a systematic review in postmenopausal women found that vitamin D supplementation improved grip strength, a widely used measure of overall muscle function.² While vitamin D isn't a substitute for strength training or eating enough protein, it's an important piece of the foundation for staying strong and active through midlife.

Technically true, practically unhelpful. The amount of vitamin D shown to support bone health is higher than the minimum needed just to avoid deficiency.⁴ "Not deficient" and "getting enough to support bone health as you age" aren't the same target.

◆ Make sure you're getting enough vitamin D: Many women don't meet their daily needs, especially during the fall and winter months. Talk to your healthcare provider about whether a supplement is appropriate for you, particularly if you have risk factors for deficiency such as limited sun exposure, darker skin (which produces less vitamin D from sunlight), spending a lot of time indoors, or being in perimenopause or menopause and concerned about bone health.

◆ Pair vitamin D with resistance training and enough protein, not instead of them: Vitamin D helps support healthy muscles, but strength comes from using them, and protein gives your body what it needs to rebuild that muscle. Aim for resistance training at least twice a week, targeting major muscle groups, along with adequate protein and calcium intake, to help maintain muscle and support bone health.

◆ Focus on consistency: Whether you're getting vitamin D from food (fatty fish or fortified foods), supplements, or both, a consistent daily routine is generally more effective than taking large doses only occasionally. Small habits, repeated over time, have the biggest impact.

If I'm not deficient, do I still need to think about my vitamin D intake?

Yes. The amount shown to support bone health is higher than the minimum needed just to avoid deficiency, so "not deficient" and "getting enough to support bone health as you age" aren't the same target.

Can vitamin D replace strength training or protein for muscle health?

No. Vitamin D may help support muscle strength, including grip strength in postmenopausal women, but it works alongside resistance training and adequate protein, not instead of them. 

The life you love deserves a strong foundation, and your bones and muscles are part of it. Getting enough vitamin D is one practical way to support them, alongside strength training, adequate protein and calcium. Start with small, consistent habits, and talk to your healthcare provider about your individual needs. Caring for yourself today is an investment in the things you want to keep doing in the years ahead.