Reality Check: Was 27 December the busiest NHS day?
The claim: Tuesday 27 December was the busiest day in the history of the National Health Service.
Reality Check verdict: In relation to attendance at type-one accident and emergency departments (the general A&E departments at big hospitals), Mr Hunt is correct. That's a reasonable measure of how busy the NHS is, but other measures suggest different days were busier.
Secretary of State for Health Jeremy Hunt made the claim on BBC Radio 4's Today programme as he thanked staff for their work over Christmas.
NHS England publishes daily statistics during the winter for several metrics to do with NHS services, so we can look into whether it is the case.
We can assume he was talking about the NHS in England only, because health is devolved, so he is not in charge of the NHS in Wales, Scotland or Northern Ireland.
The number of people attending accident and emergency departments is an important indicator of demand for hospital services.
On 27 December, there were 60,215 attendances at A&E departments.
That is a high level, but it's not the highest for the month, which was set at 60,692 on 5 December.
But it turns out that Mr Hunt was talking about only type-one A&E departments, which is what most people would think of as an A&E department.
Type-two are specialist units, such as Moorfields Eye Unit, while type-three are GP-led walk-in centres.
There were 46,315 attendances at type-one A&E departments, which is the highest of the month. Comparisons with previous years are difficult due to changes in coverage and figures not being broken down in the same way.
Another important measure is the number of emergency admissions, which was 13,715 on 27 December.
That is a high figure, but the number was higher on each of the following three days - it was 14,649 on 28 December.
Looking at the proportion of beds occupied: on 27 December, 90.5% of the total number of available beds were occupied.
That's actually quite low by the standards of last month - there were higher figures on 24 days in December.
NHS England says that the week ending 1 January 2017 was the busiest week for the NHS 111 24-hour non-emergency service since it began in August 2010, but we do not get that figure broken down by day so cannot say whether the Tuesday was the busiest day.
We also do not have daily figures for how busy other parts of the NHS were, such as GPs.