RESEARCH that I am carrying out suggests that the most important factor explaining the outcome of the Brexit referendum was anti-immigration sentiment. 

There is a widely held view that immigrants sponge off the welfare state and steal jobs from native-born Brits. 

Given that it is not possible to stop immigration from other European Union countries to the UK as a member of the EU, the only way to stem the flow of people from these countries – and solve the UK “immigration problem” – is to leave the EU.

READ MORE: New figures reveal over-50s are the fastest growing part of workforce

However, migration is a two-way street. It is often forgotten that a large number of UK citizens leave the UK to live elsewhere. 
Of this total, about half end up in other EU countries. 

Currently, there is considerable political debate – and some quibbling between the House of Lords and House of Parliament – about what is the best way to secure the right to stay of UK citizens living in other EU countries. This right is in no way guaranteed. 

Theresa May’s “solution” is a form of political blackmail. She wants to use the right of EU citizens currently in the UK to stay in the UK as a bargaining chip. 

While the House of Lords favours a decision being made before formal negotiations to leave the EU begin.

Regardless of what the outcome is for UK citizens currently living in the EU, with a “hard Brexit” the situation will be very different for those wishing to do so in the future. 

It is my view that the EU will not budge on the fundamental right of the free movement of people. In this respect, you will need to be either in or out, and the UK will be out. 

While this will not in any way stop UK citizens travelling to EU countries, it will certainly make it more expensive for them to do so. 

One of the benefits of EU membership for UK citizens is reciprocal health care. 

What this effectively means is that UK citizens get free health care in all other EU member states if they become ill. 

So, if John from Glasgow has a heart attack while on holiday in Tenerife, he is entitled by law to the same medical treatment and care that Juan from Madrid would receive in the same situation. 

Given that the Spanish health service is considered to be one 
of the best in the world (regardless of how quality is measured), John should consider himself fortunate. If he had the same heart attack while on holiday in the United States, and did not have health insurance, he would face a very large bill.

Leaving the EU means tearing up this reciprocal health care arrangement. 

This will mean that UK citizens – of any age – will need to purchase health insurance to travel to other EU member states (and vice versa) or risk considerable expense if they become ill. 

This will make, for example, holiday and business travel more expensive. 

This is a cost of Brexit that we will need to live with. 

It is of course easy to dismiss this as not being important since it is what is required when we travel to other non-EU countries anyway. 

I don’t agree with that assessment. 

What about people who want to live, or spend a large part of the year, in an EU country after Brexit? 

I expect they will be able to this with little problem except if they want to work. 

All EU countries welcome tourists and recognise the importance of tourism as an industry. 

All issue lengthy tourist visas to citizens of the United States, Canada and other rich countries, and there is no reason to believe that the UK will be treated any differently. 

It has been estimated that about one-third of UK citizens living in Spain are over 65 years of age. 

Anecdotal evidence suggests there is also a large number of older UK citizens who spend the cold months of the year in the warmer climes of Croatia, Italy, Greece and Portugal. 

With population ageing, we can expect a larger number of older people wanting to do the same in the future. 

The problem, which has not featured much (if at all) in Brexit debate, is that it will become much more expensive to stay longer-term in EU countries. 

READ MORE: New figures reveal over-50s are the fastest growing part of workforce

Those wishing to do so will be required to buy health insurance and will very likely be required to prove that they have at least minimum coverage on entry. 

My view is that this insurance will be prohibitively expensive for older people. 

Health insurance rates rise rapidly with age and this is especially true for people with an existing medical condition (such as high blood pressure). 

This is likely to be a particular problem for Scots, whose 
Poland-like life expectancy and morbidity will result in even higher health insurance costs. 

Robert E Wright is Professor of Economics at the University of Strathclyde. He recently gave evidence to the House of Lords 
on the costs of Brexit.