Japan has the highest life expectancy in the world. Girls born in Japan today can expect to live to 86. And boys will live to 80. In the UK if you are a female you expect to live until you are 82 and men are only expected to live until they are 78. So how can we catch up?

New research in the Lancet suggests Japan's success is down to three key factors. First, Japan has a universal healthcare system and it has invested in public health. Second, the Japanese are health- and hygiene-conscious. They have a good balanced diet and generally take responsibility for their health.

Third, and most importantly, Japan has not been afraid to be a bit of a nanny. Japan has sought to tackle the number of deaths from stroke by trying to cut salt consumption and prescribing the right drugs to get blood pressure under control. And they have encouraged a focus on prevention through screening programmes, checkups and getting local government and businesses in on the act.

So how do we compare? And how do we move up the table? Well we have the National Health Service, which is free at the point of need and available to all. And we spend a similar amount on healthcare as the Japanese. So we must not lose this. Taking away the NHS or cutting spending would push us further down the table.

Under considerable pressure, the coalition government has reaffirmed its commitment to the NHS and universal healthcare, and health has so far been largely spared in the cuts. This is good news. But we also need to ensure that those communities with the biggest health needs continue to get their fair share of NHS spending. Otherwise health inequalities will get worse.

The coalition's plans for public health also hold some promise. The government is proposing that the new health and wellbeing boards should bring local authorities and GPs together to take joint decisions on how to step in early and promote prevention.

Much of the gains in UK life expectancy in the last 10 years can be credited to GPs upping their game on controlling cholesterol and managing blood pressure. And the planned increase in NHS screening and prevention programmes also holds the prospect of more gains.

But diet and health focus in the UK is still a worry. Compared with Japan, we are in the midst of a public health crisis. We eat, drink and smoke the wrong things. We do it to excess. And we ignore public health advice, if we get any.

If we don't start doing something about it, we are not just going to fall behind Japan, healthcare costs are also going to go through the roof, which will inevitably mean more taxes. This was Derek Wanless's warning in his review of healthcare costs nearly 10 years ago.

The current coalition government has placed much faith in its "nudge programme": people shouldn't be told what they can and can't eat, and the government simply needs to make it easier for people to do the right things.

But will a firm nudge really be enough to stem the tide? The world's big food, drink and tobacco firms are geared up to encourage even greater consumption – an increasing problem, even for Japan. The food industry's annual advertising budget, for example, is £30bn: higher than the GDP of 70% of the world's nations. The sole aim of such advertising and marketing budgets, ranging from TV advertisements aimed at children to "supersize" marketing ploys, is increased consumption.

It should be no surprise that the excessive consumption of energy-dense, high-fat, high-salt foods, as well as sugary and alcoholic beverages, is driving the contemporary health problems of obesity, alcohol abuse, high blood pressure, and the resultant rise in heart disease, liver disease, stroke and diabetes. The resources available to counter this assault from the food industry are limited: a prime example of what the late great Harvard economist John Kenneth Galbraith called "social imbalance". For every one pound the UK government spend on healthy eating advice the top 20 food brands in the UK spend £20. Who is going to win this battle?

Still, there's hope. In many key areas, the public mood is shifting. Educated and informed consumers are increasingly forcing large corporations and retailers to improve product information and promote health-conscious foodstuffs. Restrictions on smoking in public areas are now widely accepted.

But a nudge will not be enough to switch people on to healthier lifestyles. The government needs to spend more on public health and introduce new regulation that promote health and protects children. We need to regulate big businesses and advertising that promotes harmful excess consumption. We must follow the lead of both Sweden and Norway, who have banned junk-food advertisements on TV aimed at children under 12. Finally, we need to use the tax system to change corporate and individual behaviour to encourage public health and not just create private wealth. Only then can we really move up the life expectancy league table.