We tend to think of vitamin D as the ‘sunshine vitamin’, but there's much more to it than that. And as we enter our 50s and beyond, particularly around menopause, getting enough becomes increasingly important.
From maintaining strong bones to supporting our immune system and even our gut health, vitamin D plays several important roles. Yet it's also one of those nutrients surrounded by confusing advice. Do we need supplements? Is more better? And does it matter which type we take?
As a gut health scientist and dietitian, here are six things I think every woman over 50 should know.
Vitamin D does far more than support your bones
Vitamin D is best known for helping our bodies absorb calcium, which is essential for maintaining strong bones. But its influence extends much further.
Vitamin D also supports normal muscle function and helps regulate our immune system. Interestingly, emerging research suggests it may play a role in gut health, too.
We have vitamin D receptors throughout our digestive tract, and the latest research suggests vitamin D helps maintain the gut barrier, which is our body's first line of defence against unwanted substances entering the bloodstream.
There's also growing interest in how vitamin D interacts with our gut microbiome, although we're still learning what this means for our health in practice.
You might not be getting enough
In the UK, government guidance recommends adults take 10 micrograms (400 IU) of vitamin D daily during autumn and winter.
That's because, between October and March, sunlight in the UK generally isn't strong enough for our skin to make sufficient vitamin D.
Some people are at greater risk of deficiency, including those with darker skin, limited sun exposure or conditions affecting nutrient absorption, such as coeliac disease or Crohn's disease.
Our skin's ability to produce vitamin D may also decline as we get older, although this varies considerably between individuals and isn't something that automatically happens when we reach our 50s.
For people at higher risk, supplementation may be appropriate year-round. And if you have osteoporosis, malabsorption or a suspected deficiency, speak to your healthcare professional about whether testing or a different dose is needed.
Food helps, but it's hard to get enough from diet alone
I'm always an advocate for food first, but vitamin D is one nutrient where food alone can struggle to meet our needs.
Oily fish, such as salmon, sardines and mackerel, are among the richest natural sources. Egg yolks and fortified foods, including certain breakfast cereals and plant-based milks, also contribute.
Mushrooms exposed to UV light can provide vitamin D2, although amounts vary considerably.
My advice? Include these foods as part of a varied diet, but don't assume they're enough to cover your requirements, particularly during winter.
It’s also worth noting that vitamin D is fat-soluble, so taking your supplement alongside a meal containing some fat can help absorption. No need for anything complicated, your usual breakfast or lunch will often do.
Menopause makes bone health particularly important
Here's why vitamin D deserves extra attention around menopause.
Oestrogen plays an important role in protecting our bones. As levels decline during menopause, bone breakdown can accelerate, increasing the risk of osteoporosis and fractures later in life.
Vitamin D helps us absorb calcium, but it's only one part of the picture.
Getting sufficient calcium through foods such as yogurt, calcium-set tofu and fortified alternatives is equally important. Protein supports our muscles and bones, while resistance training and weight-bearing activities help maintain strength.
And don't underestimate the value of movement. Walking, dancing and strength training can all contribute to healthier ageing.
Think of vitamin D as one member of your bone-health team, rather than the star player.
More vitamin D isn't necessarily better
It's tempting to assume that if a little vitamin D is good, a higher dose must be even better. But that's not how nutrition works.
Because vitamin D is fat-soluble, excessive amounts from supplements can build up in the body and cause dangerously high calcium levels, potentially damaging the kidneys.
For most healthy adults, the UK recommended 10 micrograms daily is a sensible starting point during winter. Unless medically advised, adults shouldn't exceed 100 micrograms (4,000 IU) daily.
Not all vitamin D supplements are created equal
Here's something many people don't realise: vitamin D comes in two main forms – D2 and D3.
D3 is the form our skin naturally produces in response to sunlight and is also found in animal-derived foods. D2 comes primarily from fungi, including UV-exposed mushrooms.
For years, the two were treated almost interchangeably. But research increasingly suggests D3 is more effective at raising and maintaining vitamin D levels.
If you're choosing a supplement, I'd generally recommend D3, so make sure to check the label. And if you're vegan, the good news is that vegan-friendly D3 derived from lichen is available.
The takeaway? You don't need expensive high-dose supplements or complicated routines. Focus on consistency, a varied diet and healthy lifestyle habits.
After all, when it comes to healthy ageing, it's rarely one nutrient that makes the difference – it's how everything works together.
Known as The Gut Health Doctor, Dr Megan Rossi is a gut-health scientist, bestselling author and founder of SMART STRAINS.