Sunshine really is the best source of vitamin D, and in these dreary months we barely see the sun, let alone spend enough time outdoors. For our bodies to synthesise vitamin D using the sun, we need 20 minutes' exposure daily without sunscreen and a good bit of skin exposed. I shiver just thinking about it!
The Scandinavians, a hardy bunch, put up screens outside to protect themselves from the cold wind and some even sunbathe nude or almost nude, on clear winter days to get their vitamin D. I can't see that happening in gardens around Ireland, so it's best we look at food sources of vitamin D.
Vitamin D is more important than you realise. It is essential for the control of cell growth, bone development, neuromuscular function, immune system regulation, stabilising moods, and lowering the risk of inflammation.
Vitamin D is also widely known to stimulate the absorption of calcium – when your body isn't producing enough vitamin D, it will try to recover some of the calcium in the blood by taking it from your bones, which interferes with your body's ability to maintain bone health as you age. Unfortunately, your body's ability to produce vitamin D declines with age, which is why a significant majority of older adults are vitamin D deficient.
Your GP can send you for a 25-hydroxy-vitamin D (25 OH vitamin D) blood test to check if you are vitamin D deficient.
You may be prescribed a supplement, but you can probably get enough vitamin D through your diet and some time outdoors.
Salmon is one of the top sources of vitamin D. Wild salmon especially is a significant source of vitamin D, more so than non-organically farmed fish. It contains the highest natural source of vitamin D – a 100g serving contains 1,059.14 IU, which is 264.79pc of your recommended daily value.
When you consume half a fillet of salmon, you get 1,400 IU of vitamin D. That is more than double needed for your day. In Ireland we produce fantastic fresh salmon and you can also use tinned salmon, especially tinned wild salmon. You're not going to eat salmon every day, but aim for at least one portion a week.
Tuna also contains significant amounts of vitamin D, especially when enjoyed raw as sushi or as a Scandinavian type dish where it is 'cooked' with lemon juice and dill, instead of using salmon.
If using tinned tuna, use tuna canned in oil rather than water as it will contain more Vitamin D. Per 100g serving, tuna packed in oil will give you 39pc of the recommended daily amount.
I grew up on tuna in salads and sandwiches and to this day am partial to a tuna mayo quesadilla with plenty of spring onion and hot sauce.
3 Fortified Milk
Dairy products are already high in dairy, so it makes sense that they are fortified with vitamin D, to get the most benefits. Avonmore now produces a low fat fortified Supermilk and recently a full fat version, which is important for younger children who should be having full fat dairy products to help with the absorption of nutrients. I've started buying it and use it to cook with, such as cheese sauces, and notice no difference in flavour or texture.
4 Fortified Cereals
Many breakfast cereals on the market are fortified with extra vitamins and minerals, including vitamin D. Do exercise caution though and choose a cereal that is low in sugar and salt and has no hydrogenated oils which are the dangerous trans fats. I would also opt for a wholegrain, high fibre version. Served with fortified dairy milk or soy milk, this makes a very good start to the day.
One egg from a free-range chicken contains 26.50 IU of vitamin D. For vegetarians who eat eggs, they're an excellent source of vitamin B12 and protein as well.
A meal with two large eggs contains about one-tenth of your daily dose of vitamin D. You can eat up to 14 eggs a week without it affecting your cholesterol but six to seven eggs per week is the recommended amount.
Mushrooms have the ability to produce vitamin D when exposed to sunlight, similar to humans. Portobello mushrooms have greater amounts of vitamin D, with 400 IU per three-ounce serving. Shiitake mushrooms are also considered a good source of vitamin D, containing 17.40 IU per 87-gram serving.
Mushrooms naturally grow in the dark, but certain varieties are now being grown in ultraviolet light to specifically produce more vitamin D.
You can buy dried shiitake mushrooms that are wonderful reconstituted and used in risottos and soups, and to enrich gravies and stews.
7 Soy and Soy Products
Many soy products are fortified with calcium and vitamin D. A 100g serving can contain up to 39pc of your recommended daily vitamin D. Brands vary greatly, so do check the labels.
Also, just because many of these products are considered 'health' foods, doesn't mean that they are not high in sugar and salt. Health shops stock a good range of soy products and supermarkets have improved greatly in their selection.
Pork is also high in vitamin D, but it varies greatly between cuts and quality of meat. Also, curing and smoking pork can add significantly to the salt content.
Key things to look for is that the pork you're buying is free from phosphates and low in nitrates (used in curing). Do also keep the saturated fat content in mind.
I prefer to buy my pork from a butcher where I know the pigs have been raised and fed properly. Most families enjoy sausages, so again be choosy, there are many excellent pork products produced in Ireland.
9 Cod Liver Oil
Cod liver oil is another good alternative for vitamin D. It contains high amounts of omega-3 fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), which are also good factors for a healthy heart.
Every 100-gram serving of cod liver oil provides 10,001 IU of vitamin D. Cod liver oil would not be my favourite source of vitamin D as it also contains high levels of vitamin A, which should be taken with caution.
10 Ricotta Cheese
Cheese is pretty high in vitamin D in general, but ricotta cheese stands head and shoulders above the rest with about five times the amount of vitamin D in comparison to other cheeses.
It would still take quite a number of servings to make up your daily needs, but do make it a part of your diet.
Ricotta is actually very easy to make, and if you use a fortified milk, you are guaranteed a nutrient rich cheese.
Herby Tartare Homemade Ricotta with Smoked Salmon
Makes 1 bowl
Ireland produces the most gorgeous, creamy, rich milk and cream, so naturally these produce world-famous butter and cheeses. Why not enjoy the fun of making your own cheese with the best raw ingredients? It's a bit show-offy, but that's allowed sometimes.
* 1 litre full-fat milk (use full fat Avonmore Supermilk)
* 500ml cream
* 1 tsp sea salt
* 3 tbsp white wine vinegar
* 1/2 red onion, finely chopped
* 2 tbsp chopped fresh dill
* 2 tbsp finely chopped fresh chives
* 1 tbsp small capers
* juice of 1/2 lemon
* salt and freshly ground black pepper
* Irish brown soda bread
* smoked salmon
* lemon wedges
* dill fronds
* Mix the milk, cream and salt in a large pot. Bring to the boil, stirring to dissolve the salt. Turn off the heat and stir in the vinegar. The mixture will go lumpy and will curdle.
* Line a large colander or sieve with 2 layers of muslin. Stand this over a large bowl. Pour the curdled milk into the colander. Allow to stand for 1 hour. Discard the liquid that collects in the bowl.
* You'll be left with thick, creamy ricotta cheese that's ready to use as is or seasoned. Add the red onion, dill, chives, capers, lemon juice and some salt and pepper. Cover and refrigerate for up to four days.
* This is delicious served on toasted rustic bread with smoked salmon.
Ish Factor: Smoked salmon is so quintessentially Irish. When I first moved here I lived on brown soda bread and smoked salmon for the first few weeks. It will shock the puritans, but I do freeze packs of smoked salmon so that I always have some. My favourite light meal is a poached egg, steamed asparagus and smoked salmon.
- All recipes taken from 'Delish' and 'Relish' cookbooks by Rozanne Stevens. To book a healthy cookery class or to order a book, log onto www.rozannestevens.com
- Twitter: @RozanneStevens