As I stood by and watched Boris Johnson’s carefully orchestrated procession out of the Addenbrooke’s treatment centre in Cambridge last week, I was angered by his cowardice and his clear desire not to be questioned. My final medical exams are fast approaching, and I left the clinic pondering some of the complex conditions I’d just seen. Going up to the prime minister and speaking my mind about the state of the government was not part of my revision plan.

Like the majority of people working in Addenbrooke’s, I had no idea Johnson was visiting that day. Most staff didn’t even know he was there until after he had left – he clearly wanted to get some nice photos in a lab coat and get out of there. As just another young person who is deeply concerned about the future of our planet, as well as our NHS, I decided to try my luck at speaking to Johnson. But the security guard who quickly ushered him away made it very clear I wasn’t allowed to ask questions. Of course politicians’ security must be protected, but what kind of prime minister needs security to protect him from the public’s questions? Only a government whose record is hurt by the facts, led by a man unable to give straight answers.

More and more junior doctors are choosing not to continue training after their first two years because of exhaustion and stress

After my attempt to speak to Johnson, some journalists approached me and filmed me talking about the NHS, and the subsequent video was widely shared online and picked up by the national media. I hope that, as a result of my interview, Johnson heeds my call for evidence-based politics, and uses his position of leadership to give us more than just slogans and false promises. As a sixth-year medical student, I might not work in our NHS yet, but I have already seen enough to know why Johnson was so unwilling to meet frontline NHS staff openly. As I’m not yet a doctor, I’m perhaps more able to say things that others might be afraid to, so I want people to hear what other doctors have been saying for years: that the NHS has been relentlessly underfunded by the Conservative government.

Medical students like me sit on the periphery of medical care provision, so I see the day-to-day reality of funding shortages. I’ve seen the system stretched in many directions as I’ve trained in different hospitals and departments. Funding “gaps”, as they are often euphemistically labelled, cause increasing delays in patients getting the care they need: your grandmother waiting for her knee operation; or worse, for cancer treatment. There’s never anything truly elective about surgery on the NHS – patients don’t have surgery for fun – but “elective” operations are increasingly being cancelled. It’s important to recognise the emotional effects of these cancellations: parents being told that the life-saving surgery that was planned for their child today cannot go ahead any more. It’s heartbreaking, and it’s just not good enough.

I think patients are perhaps most aware of having to wait longer and longer to see their GPs. Despite the Conservatives’ promises to increase the number of GPs, it keeps falling.

In his book Direct Democracy, the former health secretary Jeremy Hunt uses the failings of the NHS to push his agenda of fast-forwarding the marketisation of our services. We’ve already seen increasing provision from independent providers, totalling £9.2bn in 2018-19. But there have been serious failings among some of these private companies, notably in the care of vulnerable young people, and also the treatment of adults with autism, learning disabilities and serious mental health problems.

This increasing privatisation is also incredibly opaque – data about levels of private service provision by sector isn’t even collected. If you were an insincere politician, perpetuating the NHS crisis would be a clever way to argue that we couldn’t continue with our current wonderful system, which provides free care for all at the point of use. It’s easier to deconstruct the NHS if you haven’t got anyone to work in it any more; the staffing crisis is such that about one in 12 positions are currently unfilled.

If all goes to plan, I will start my first job as a junior doctor next August. While I’m filled with excitement about being able to do the job I’m training for, I also worry that it will be tough. More and more junior doctors are choosing not to continue training after their first two years’ work because of exhaustion and stress – will this be me in three years?

I can’t offer solutions to all the complex issues of our health service. But I can say that we deserve moral integrity and truthful use of evidence by politicians. As a medical student, the work I do is evidence-based, but the government is ignoring the facts. The reality is that the NHS is underfunded and understaffed. Our prime minister doesn’t hold personal responsibility for the entire state of the NHS, but he shouldn’t pretend that hollow promises to build 40 new hospitals (when funding is only confirmed for six) is going to solve the problem.

If Johnson really wants to engage with NHS staff, he needs to go beyond photo opportunities, and listen to what people on the ground are saying. Reading the Doctors’ Association’s election priorities – which include restoring funding and valuing our workforce – would be a good place to start.

After my encounter with Johnson’s team and then with the press, I’m overwhelmed by the positive response I have received for speaking out. But I’m still waiting for answers from the prime minister.

• Julia Simons is a medical student