Professor Sir Michael Marmot said the rise in life expectancy had "slowed dramatically" since 2010, while health inequalities were widening between the most and least deprived parts of the country.
The new report, Health Equity In England: The Marmot Review 10 Years On, found an increase in the North-South health gap, with the largest decreases in life expectancy seen in the most deprived 10 per cent of neighbourhoods in the North East, and the largest increases in the least deprived 10 per cent of neighbourhoods in London.
It also found that life expectancy in men had risen by about half a year from 79.01 in 2010-12 to 79.56 in 2016-18, while in women it rose by about a third of a year from 82.83 to 83.18 during the same period.
Prof Marmot said that this compared to life expectancy generally improving by about one year every four years for a century up until 2010.
The difference in life expectancy at birth between the least and most deprived deciles was 9.5 years for men and 7.7 years for women in 2016-18, rising from 9.1 and 6.8 respectively in 2010-12, the report added.
Prof Marmot said: "England is faltering. From the beginning of the 20th century, England experienced continuous improvements in life expectancy but from 2011 these improvements slowed dramatically, almost grinding to a halt.
He added: "England has lost a decade. Pretty much - with a few dips and bounces - life expectancy improved about one year every four years from the end of the 19th century until 2010, then it slowed down dramatically.
"If health has stopped improving, that means society has stopped improving and if health inequalities continue and in fact increase, that means inequalities in society have been increasing.
"A similar lost decade would mean continuing worsening of health inequalities and continued flatlining of life expectancy."
The report estimated that the cost of failing to tackle these issues would be about £82 billion a year in lost taxes, higher welfare payments and increased NHS and social care costs.
It called on the Government to reduce child poverty to 10 per cent, reduce "poor quality, low-paid and insecure" work, make sure the national living wage and benefits give people the minimum needed for a healthy life, and invest more in the most deprived areas.
The report also found an increase in the North-South health gap, with the largest decreases in life expectancy seen in the most deprived 10 per cent of neighbourhoods in the North East, and the largest increases in the least deprived 10% of neighbourhoods in London.
It also said that child poverty after housing costs had risen from 27 per cent in 2010-11 to 30 per cent in 2017-18, while among single parents who were not in work, 70 per cent of children were in poverty.
Prof Marmot said that while poverty was an issue, austerity had taken its toll on equity and health.
He added: "Austerity has taken a significant toll on equity and health and it is likely to continue to do so... if you ask me if that is the reason for the worsening health picture, I'd say it is highly likely that is responsible for the life expectancy flatlining, people's health deteriorating and the widening of health inequalities."
The report said that while there were growing regional inequalities in life expectancy, "people living in affluent areas in every region are living longer".
It said: "It matters little for life expectancy where those areas are in the country. Region matters much more for people living in deprived areas."
In the last decade life expectancy for men in the most deprived 10 percent of neighbourhoods decreased in the North East, Yorkshire and the Humber and the East of England
Dr Jennifer Dixon, chief executive of the Health Foundation, which commissioned the report, said: "To 'level up' the country as the Government aims, it must take action to level up the health and wellbeing of the population.
"We urgently need a new national health inequalities strategy, backed by investment in the factors that have the most powerful impact on health, such as early years and youth services, housing, education, social security and good quality work.
"Having secured new support from ‘red wall’ areas that are at the sharp end of rising health inequalities, the government now has a real opportunity to show leadership on improving health.
"‘Levelling up’ will require the government to go further than investment in infrastructure – building bridges, train lines and new hospitals.
"It must also invest in the circumstances in which people live that have powerful impacts on their health and wellbeing – such as poverty, employment, housing and education."
In a statement, Health Secretary Matt Hancock said: “Every single one of us, no matter who we are, where we live, or our social circumstances, deserves to lead a long and healthy life.
“The ultimate goal of the NHS is to increase healthy life expectancy, and this Government is determined to narrow the gap by levelling up access to healthcare across England.
“I thank Professor Sir Michael Marmot for his dedicated work to shine a light on this vital issue. His findings show just how important this agenda is, and renew my determination to level up health life expectancy across our country. After all, levelling up health is the most important levelling up of all.
“There is still much more to do, and our bold prevention agenda, record £33.9 billion a year investment in the NHS, and world-leading plans to improve children’s health will help ensure every person can lead a long and healthy life.”