One in eight over-55s suffer from vitamin D deficiency. Margaret Jennings hears how fortified foods are helping to keep our bones strong.

HOW has the winter been for you? 

One in eight of us in Ireland over the age of 55 suffers from vitamin D deficiency which, among other functions, regulates how our body uses calcium, so that we can have healthy bones.

Usually dubbed the “sunshine vitamin” it’s been grabbing the headlines in recent years because we now know that during those winter months, unless we supplement, or get vitamin D from our limited dietary sources, our health is even more at risk, as we age.

“While vitamin D can be synthesised in skin on exposure to summer sunlight, this happens much less during the winter months and furthermore, in summer, standard public health advice is to avoid over-exposure due to concerns over skin damage and cancer,” says Kevin Cashman, professor of food and health at the School of Food and Nutritional Sciences at UCC.

Ageing: How to keep your bones strong during the winter months

Prof Cashman has, together with his colleague Professor Mairead Kiely, been co-ordinating the EU-funded ODIN project, Europe’s first fully comparable evaluation of vitamin D status and dietary intake, which is due to end its four-year run in October.

“The 12% — or one in eight — was in a national survey of 18-90-year-olds in Ireland, but in general it is fairly similar in pre-55 versus over-55-year-olds,” says Prof Cashman. 

“Many papers will say there is a higher prevalence of low vitamin D in older people compared to younger — because skin production becomes a little less efficient with age.

“But in the Irish population, people over 55 years, especially women, are more aware and a higher percentage of this age-group take supplements, so all in all, the 12% for the whole adult population — younger and older — is about right.”

Ageing: How to keep your bones strong during the winter months

It’s good to hear we women are responding by supplementing, because medical research suggests lack of vitamin D in the over-55s can increase our risk of falls and fractures since it helps our body absorb the calcium needed for bone health.

According to the Irish Osteoporosis Society (IOS), substantial clinical evidence demonstrates that low calcium and vitamin D intake and/or poor absorption are linked to an increased risk of hip fractures as we age.

“Many people are not aware of the devastating effects of a hip fracture and the fact that 90% of hip fractures are due to osteoporosis,” says the IOS website.

Ageing: How to keep your bones strong during the winter months

It points out that:

  • 20% of Irish people aged 60+ who fracture their hip will die within 6-12 months;
  • 50% of Irish people aged 60+ who fracture their hip will not be able to wash, dress, or walk across a room unaided;
  • Only 30% of Irish people aged 60+ who fracture their hip will regain their independence. However once a person has fractured a hip, this places them at a higher risk of fracturing again.

Considering our limited sources of the vitamin, from food — such as in fatty fish, beef liver, cheese, and egg yolks — one of the main drives behind the ODIN project was to focus on how we could get vitamin D in our diet through fortification, that is simulating sunshine by treating food products with light.

Emerging as one of the big players among fortified foods are UV (ultraviolet) treated mushrooms, a market that has been developed by Monaghan Mushrooms. 

Ageing: How to keep your bones strong during the winter months

It says vitamin D mushrooms taste just like regular brown mushrooms, but “have the benefit of providing 100% of the recommended daily amount of vitamin D in just three mushrooms” — a claim supported by the European Food Information Council.

Prof Cashman says mushrooms are one of the products that seem to work if given to people during the winter who have low vitamin D, but possibly don’t improve vitamin D status further in people who have good levels to begin with.

Why they work well is that they have “a pre-vitamin D compound” capacity that, once exposed to UVB light, transforms into vitamin D (as vitamin D2). 

“This is similar to our skin having a pre-vitamin D which, when we are exposed to UVB light — most usually from summer sunlight — transforms it into vitamin D3,” he says.

The process does not work on plants, for example, because they don’t possess that pre-vitamin D compound.

Another success story has been a low-fat, vitamin D fortified cheese, produced by a Dutch dairy company that is a partner to the ODIN project.

Ageing: How to keep your bones strong during the winter months

It conducted a human dietary intervention study in which post-menopausal women consumed a reduced-fat, Gouda-type cheese, either unfortified or fortified with vitamin D3, to test the potential of the cheese to prevent vitamin D deficiency during winter.

Overall, the eight-week randomised controlled trial showed that consumption of the cheese was effective in counter-acting vitamin D deficiency during winter months in the women in Greece.

Aside from the obvious boost to our health, the fortified foods market could also benefit public health spending, when you consider that one hip fracture costs €55,000, according to the IOS, and one person fractures a hip every 30 seconds in the EU.

So in the future we may be hearing more about eating up our mushrooms, as well as those health-enhancing colourful veg that normally get top billing.

Ageing quote

“We need to love ourselves first, in all our glory and imperfections"

— John Lennon

Silver surfer

A rare glimpse inside the late Elizabeth Taylor’s home 


The Menu was delighted to make recent mention of a new UCC postgraduate diploma in Irish food culture and is equally pleased to announce availability of two new bursaries for same.The Menu: Food news with Joe McNamee

More From The Irish Examiner