Official statistics are failing to paint an accurate picture of people's health outside our cities, says the document.
This lack of information is masking pockets of significant deprivation and poor health in rural areas.
See also: Shortage of rural GPs risks rural health
The report, called Health in Rural Areas, aims to dispel the myth that rural areas are affluent and idyllic communities.
One sixth of areas with the worst health and deprivation levels in the country are located in rural areas, it says.
Councils are warning of the increased pressures they face in meeting the needs of an ageing rural population, which is also a longer distance from health services.
Izzi Seccombe, who chairs the LGA's community wellbeing board, said: "We often think of rural areas as picture-postcard scenes of rolling green fields and farming land, yet this idyllic image is masking pockets of deprivation and poor health.
"Although many rural areas are affluent, this is not the case for everywhere. The north/south divide can be seen in the countryside as well as the cities."
Rural areas make up 85% of the land in England and 9.8m people (19% of the population) live in rural communities – a number that is increasing and ageing.
On average, 23.5% of the rural population is over 65 compared with 16.3% of the population in urban areas, according to Rural England.
Some rural areas – including in the south, south west, and East Anglia – have the largest proportion of "oldest older" residents who are aged 85 and over.
The study says this is creating further challenges as older people generally experience worse health and have a greater need of health and care services.
Separate figures show that 80% of rural residents live within 4km of a GP surgery, compared with 98% of the urban population.
Only 55% of rural households are within 8km of a hospital compared to 97% of urban households.
To address the issue, the study suggests improvements are needed in government data to capture the health of rural communities – and to help councils plan how they provide services that better meet people's health needs.
And within even the wealthiest rural areas, there are pockets of real hardship, ill health and inequalities.
Councillor Sercombe said: "Rural communities are also increasingly older, and older people often experience worse health and have greater need of health and care services.
"We are also concerned that the make do attitude and reluctance to make a fuss of some older rural residents means they may not seek out health care or treatment when they need it.
"This stores up worse problems for later on where they require far more serious and emergency care.
"The remoteness of our rural communities from their nearest point of contact with a GP or hospital can leave those residents cut off from getting vital support.
"The health of our rural residents is just as important as those in our towns and cities. They must not be forgotten or left behind."
Duncan Selbie, Chief Executive of Public Health England, said the study publication busts the myth that poverty, deprivation and ill health are confined to urban, inner city areas.
"Rural areas are very diverse environments with differing needs, particularly in remote places," he said.
"Local authorities are already finding new and imaginative ways of reaching out to people in remote communities who so often go unnoticed.
"This report offers a number of great examples that other areas can use to ensure they do not miss out on the opportunity for better health and wellbeing."
A full copy of the report can be downloaded here.