Ill people are being urged to seek help earlier as part of a plan to keep more patients out of A&E.
Those who are elderly or frail or who have an existing health condition made worse in winter - such as breathing problems - should not leave it too late to seek help, according to NHS England.
It said A&E departments become congested in winter due to a much higher proportion of frail and elderly patients who require "much more assessment in A&E".
In the absence of alternatives, these people often need a hospital bed, it added.
In winter, the NHS experiences more trusts breaching the national waiting times target for patients to be seen within four hours.
The target covers all A&E types, including minor injury units and walk-in centres, and relates to the number discharged, admitted or transferred within four hours of arrival.
Figures released last month showed the number of A&E units failing to meet the Government four-hour target had almost trebled in a year.
Some 39 departments failed to meet the target of seeing 95% of patients within four hours during the period July to September, compared with 14 units during the same period in 2012.
The NHS as a whole across England was still hitting the target, but only because some units performed way above the target, with some consistently hitting 100%.
Analysis by NHS England, newly published, showed the average (median) time in A&E for patients not admitted to hospital was one hour 49 minutes.
It said fewer than 5% of these patients spent four hours or longer in A&E.
For patients who needed admitting to a hospital bed, the median time in A&E was three hours and 37 minutes.
NHS England said it was these patients who made up the majority who exceeded the four-hour target.
For those aged over 75, there was a greater than 80% chance of needing admission from A&E, compared to less than 20% for the under-30s, it added.
Professor Keith Willett, national clinical director for acute care for NHS England, said: "Our A&Es are a safety net.
"They are trusted by the public.
"They reflect what is going on in our communities and the pressures that build in other parts of the health and social care system.
"The pinch point in winter is the increase in the number of emergency admissions - patients predominantly with respiratory conditions or transient worsening of other chronic conditions usually brought on by the cold weather, reduced activity and viruses.
"Thanks to the hard work and dedication of staff, average waits in A&E are low.
"However, problems arise when a patient needs admitting to hospital.
"Most of those who need a stay in hospital are our elders and the vulnerable who have increased care needs as much as medical need.
"Once in A&E they need a bed from the outset and until they are discharged from hospital and, if the support to return them to their home is limited, delays occur and new patients cannot be received."
A report last month from the National Audit Office (NAO) found many emergency admissions through A&E were avoidable and many patients stayed in hospital "longer than is necessary".
In 2012/13, more than a quarter of all patients attending major A&E departments were admitted to hospital, up from 19% in 2003/04.
Only a quarter of this rise was due to an increase in the number of people attending A&E, with the rest due to a higher admission rate.
Natural Immune System Boosters
Professor Mike Morgan, national clinical director for respiratory conditions at NHS England, said: "Each winter we see a spike in the number of emergency admissions for patients that are triggered by respiratory problems.
"In the elderly, minor respiratory illness, such as the common cold, can prompt care needs associated with frailty.
"My message to the public is simple: look after yourself this winter.
"If you know someone who is frail or elderly or has an existing health problem and they are feeling unwell, encourage them to seek early advice, go to their local pharmacy or GP before one problem leads to another and they end up in hospital.
"People with existing lung conditions should follow their self-management plans and seek help if uncertain."
A Department of Health spokeswoman said:"Across the country, A&E departments have been seeing 95% of their patients within four hours since the end of April.
"But with a million more people visiting A&E compared to three years ago, we know the system is under pressure.
"That's why we are tackling both the short and long-term problems: transforming out of hospital care by renegotiating the GP contract, agreeing a £3.8 billion integration fund to join up the health and social care system, and backing A&Es with £250 million to prepare for this winter.
"Winter is always tough, but the NHS has never been more prepared."