A disabled former soldier who said he is so poor that he lost 16kg (2st 7lb) due to a lack of food is among the contributors to the first United Nations investigation into extreme poverty into the UK.

Alexander Tiffin, a 30-year old from the Scottish Highlands, sent a diary of his life on universal credit to Prof Philip Alston, the UN rapporteur on extreme poverty and human rights, who is coming to Britain in November.

The eminent international human rights lawyer called for submissions from anyone in the UK to establish “the most significant human rights violations experienced by people living in poverty and extreme poverty in the UK”. He is interested in the impact of austerity, universal credit, the advent of computer algorithms making decisions on welfare matters, and Brexit.

Anyone taking part has been asked to set out in no more than 2,500 words what is happening, where he should go and what he should look at. He has set a deadline of 14 September for submissions and academics, thinktanks and charities are among those drafting responses.

The visit is set to be politically controversial. Alston conducted a similar exercise in the US earlier this year, which resulted in public clashes with the Trump administration. In the UK, he wants to know “to what extent austerity has been necessary” and its impact on public services including police, firefighting and libraries.

He will also consider how Brexit might affect people living in poverty. Alston defines extreme poverty as “a lack of income, a lack of access to basic services, and social exclusion”.

Facebook Twitter Pinterest One of the most poverty-stricken coastal towns in the UK, Barrow-in-Furness. Photograph: Andy Hall/The Observer

The government has already said in response that household incomes “have never been higher and there are 1 million fewer people living in absolute poverty than in 2010, including 300,000 children”.



The Centre for Social Justice, a right-leaning thinktank founded by Iain Duncan Smith, who set up universal credit as work and pensions secretary, said it will not make a submission.



“Universal credit is one of the most effective poverty-fighting tools in existence,” said Edward Davies, the head of policy. “When it is fully rolled out, hundreds of thousands more people will have a job as a result.”

Tiffin’s diary of life on universal credit is among the most striking contributions so far. The wheelchair user told Alston he is living off £95.35 a fortnight in universal credit payments and that after paying for his electricity and gas, fuel for his adapted car, broadband connection, TV licence and baby milk for his youngest son, he is left with £10.50 for two weeks.

“At one time in February, I had no food at all for two weeks,” he wrote. “I probably ate on less than a quarter of the days in that month. I just had nothing. I lost two and a half stone … my hair has started falling out and my teeth are loose due to a lack of vitamin intake.”

On 8 May, he wrote: “I wanted to be able to make myself some sandwiches, so I bought a loaf of bread for 45p and a small block of cheese for £1.72. This left me with £3.30 [with 10 days to go until the next payment]. I must admit I felt bad after buying it as I shouldn’t have wasted the money.”

Tiffin has suffered from mental health problems. He is a Muslim convert and was recently admonished by a court for threatening to kill unbelievers. Police considered he was “an idiot” rather than a terrorist and he was not punished. He said the incident occurred when he was going through a complete breakdown.

Facebook Twitter Pinterest Sanitary products are distributed at a food bank in Aberdeen, Scotland. Photograph: Murdo Macleod/The Guardian

Human Rights Watch, an organisation more often associated with defending rights in countries such as Russia, China, Syria, and India, is planning to tell Alston about food poverty in the UK.

“There is a lot of hunger that goes under the radar, ranging from parents skipping meals, kids showing up to school hungry, and schools and families relying on low-cost, redistributed surplus food to make ends meet,” said Kartik Raj, a HRW researcher for western Europe.

“People have a right to food and an adequate standard of living. These are human rights the government is obliged to ensure under international treaties it has signed. If the fifth largest economy in the world is failing to ensure that basic minimum, or letting things get worse, particularly for those who are least well off, then that is certainly something we will be bringing to the rapporteur’s attention.”

The Trussell Trust, which runs food banks, said it will tell Alston how food bank use rose 52% in areas where universal credit was rolled out, compared with 14% where it wasn’t or had only just been launched.

The Joseph Rowntree Foundation said it will urge Alston to examine how tougher benefit sanctions lead to greater destitution, which means people not being able to keep warm, fed, dry and clean. It found that last year 1.5 million people fell into destitution at some point – just over one in 50 people – with the highest levels in Manchester, Liverpool and Middlesbrough.

“Destitution cuts off your ability to have a decent life and affects mental and physical health and the opportunities for you and your children in the future,” said Chris Goulden, a deputy director of the JRF.

Aoife Nolan, a professor of international human rights law at the University of Nottingham, said: “The key issue he has to come and see is welfare reform, deliberate actions which have negatively impacted the enjoyment of human rights for disabled people and children in particular.”

The right to an adequate standard of living is enshrined in the UN convention on the rights of the child and, Nolan said, it is being breached because these rights were not being extended as they should and minimum thresholds are being breached.

The government has said it is its policy to accept and facilitate visits by UN rapporteurs.