I AM intrigued by the article by Kathleen Nutt about vitamin D and its potential benefits against the coronavirus (Call to send vitamin D to every Scots home, April 9).

Vitamin D reports have mushroomed in the last decade, mostly claiming that it has benefits beyond its established role in building and maintaining healthy bones. In northern climates, where for around half the year sun exposure is not enough for it to be the only source of the vitamin, many older people who can’t maintain good nutrition do need supplements. Canadian pensioners are routinely given it, and we in Scotland should probably follow that example.

READ MORE: Scottish Government 'should send vitamin D to every Scottish home'

However, our main source of the vitamin is food. There is plenty of vitamin D in eggs, oily fish, liver, and in foods such as cereals that for generations have been loaded with vitamin D.

Most of us have adequate vitamin D in our circulations and tissues. If everyone takes extra, will that make a difference to our resistance to viruses? The jury is still very much out on that, despite the studies quoted in the article. I was unhappy that the senior doctor Kathleen quoted was unwilling to be named. Was he or she afraid to be drawn into debate about his or her stance?

READ MORE: Scottish GP surgeries to stay open over Easter weekend

I would like to know more, too, about the Trinity College report that vitamin D “helps prevent respiratory illness and benefits immune function”. Was this to do with vitamin D supplements, or based on the natural vitamin D levels in the subjects studied? Are supplements just as effective as eating foods rich in vitamin D? We need to know much more about their beneficial effects and their downsides before recommending them to everyone.

Advising whole populations to take other forms of vitamin supplement has a bad history, and has had bad endings.

Dr Tom Smith
Girvan, Ayrshire

THE letters in The National about Vitamin D were the first mention of a matter that has been in my mind since the disease was reported. This is, when is our government going to offer some advice on resisting the infection by dietary and regime means? Well done for your constructive contribution.

If this infection lasts for any period we will need to be awareof the value of a carefully balanced diet as a means of combating it, as the West has been described as the most unhealthy population in the world.

During and after World War Two, orange juice and cod liver oil were issued by the government with milk for growing children. The milk was to provide calcium and prevent rickets. It was infamously ended by Mrs Thatcher. The concentrated orange juice gave Vitamin C, which supplies interferon which is made by the cells when under viral attack and it is a vitamin involved in antibody responses. Cod liver oil provides vitamin D and is otherwise the main dietary source of the sunshine vitamin as described in your piece.

Scotland’s population has probably always relied on oily fish for its vitamin D. Apprentices used to object being fed with the readily available salmon. Trout could be guddled. From our sea came herring, mackerel and cod. Sardines were a childhood staple which are tasty yet.

But now we have this source of nourishment cut off by the tying up of our fishing fleet. Even if it went out, there are few cod. These sensible people who sunbathe in parks to absorb vitamin D are moved on by police.

Lastly, the role of eight hours of sound sleep as the way that our body builds up immunity must also be underlined. This process is interfered with by alcohol or caffeine, or upset by stress.

This is a lesson that politicians and health professionals must also remember.

Iain WD Forde
Scotlandwell

THE biggest outdoors organisation here in Norway has just put up big posters proclaiming: “Nature is Open 24/7”, encouraging people to get outdoors in these coronavirus lockdown times. The government is actively supporting this campaign.

Quite a contrast with Scotland and UK, where one trip out for exercise per day is allowed. Otherwise you should stay indoors. Norwegians see no harm at all in being out in Nature as long as they like, as long as they observe social distancing.

Mike Fergus
Oslo, Norway

DURING this period of self-isolation and a very limited outing to my local Co-op for essentials, I have heard a new buzzword, namely “waninwanoot”, this to comply with social distancing measures, as there are only a certain amount of customers allowed in store at any one time and is necessary during busy periods.

I’m convinced that when we are through this epidemic, it will not have been the Queen, Boris Johnson or Nicola Sturgeon that got us through, but it will have been waninwanoot whit done it. With many thanks to the staff at Beith co-op.

Terry Keegans
Beith, North Ayrshire

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