The five-a-day campaign is one of the most recognised but it has its critics

The 'five-a-day' campaign is one of the most recognised but it has its critics

The latest intervention in the diet and health debate in the UK hit the headlines on 1 April. It was not an April Fool but the findings of research conducted at University College London (UCL) that we should be eating seven portions of fruit or vegetables a day may have prompted a wry smile from those who struggle to get near the current 'five-a-day' recommendation.

The research examined the diets of 65,226 men and women in England between 2001 and 2013, and found that those who ate seven or more portions of fruit or vegetables a day had a 42% lower risk of death at any point in time than those who ate only one. The research revealed people who ate seven portions of fruit or vegetables a day reduced their risk of dying of cancer and heart disease by 25% and 31% respectively.

The UCL study put the 'five-a-day' campaign in the media spotlight, and raises some interesting and important questions.

First, while 'five-a-day' is viewed to be among the more successful public health campaigns, it is clear many people fail to get to the 'five-a-day' mark, so raising the recommendation to seven-a-day may be an unrealistic aim, particularly in terms of reaching people most at risk.

This facet of the debate also throws up an epidemiological problem with such research. The fact is the group eating more fruit and vegetables are probably doing many other things to prevent illness and live more healthily than those who are not. The higher mortality among those eating less fruit and vegetables may derive from other lifestyle factors, though the study's authors did say they had tried to take this into account.

Among other factors, this leads some to question the validity of the five-a-day message. Among them is the campaigning nutritionist, Zoë Harcombe, who maintains the 'five-a-day' advice - and similar advice in other countries - is not evidence-based, and places too much emphasis on fruit and vegetables at the expense of other food groups. 

In her blog, Harcombe suggests five was chosen because it was "a memorable number", and because it seemed achievable. The point about the arbitrariness of the advice is to a degree borne out by the significant variation in advice across different countries.

In Denmark, the recommendation is for six a day, while in Ireland the message is for at least four a day. The recommendation in the US is for 2.5 cups of vegetables and 2.5 cups of fruit every day, while Australia also differentiates between fruit and vegetables, urging people to consume five portions of vegetables and two of fruit.

Harcombe suggests the recommendations are arbitrary and that 'five-a-day' was "never the outcome of evidence-based, thoroughly researched, scientific investigation". She adds that "it was a marketing campaign – and the most successful nutrition marketing campaign that the world has seen".

As is clear by the endorsements it receives, many in the public health community strongly support the five-a-day message. They take the pragmatic view that it may not be perfect but in general it does far more good than harm. Malcolm Clark, coordinator of the Children's Food Campaign, says he rates the 'five-a-day' campaign as among "the most successful public health interventions of recent times".

However, the point about this being an extremely successful campaign in terms of public awareness raises another important question and one that is extremely pertinent to food manufacturers. The success and traction of the 'five-a-day' campaign makes it a compelling on-pack message to place on foods.

However, this is an area where the benefits of the five-a-day message could be substantially compromised. There has been concern among health campaigners for years that the five-a-day slogan is often added to processed foods, such as fruit juices, smoothies, canned vegetables and tinned fruit, with high levels of sugar or salt. These could be said to provide a portion of fruit or vegetable but in other regards are nutritionally questionable. 

These products benefit from the consumer awareness of the five-a-day campaign but in reality do not make a positive contribution to diets. Nutritional standards regarding added sugar only apply when the official 'five-a-day' logo is being used.

The UCL research bears out the significance of this failing. The researchers found no evidence of a "significant benefit" from fruit juice, while canned and frozen fruit appeared "to increase risk of death by 17% per portion". 

While the food industry stresses it wishes to make a positive contribution to tackling diet-related health problems, the presence of such products on the market does it little credit, and represents the kind of reputational weak spot that can compromise its position as a responsible stakeholder.

The next iteration in the UK government's Public Health Responsibility Deal will address the issue of food promotion and marketing. It will deal with some of the most contentious issues for the food industry within the diet and health debate and it is perhaps no surprise it is taking longer to finalise than had been expected. Clark says he would like to see some form of undertaking on the responsible use of the five-a-day message included, qualifying his support for the five-a-day campaign with a wish for it to be "better policed".

Arguably, the question of how consumers perceive products marketed as one of their 'five-a-day' day does not pertain solely to those containing added sugar. Products containing only natural sugars are still nonetheless high in sugar and in calories, and evidence suggests this also is not well understood by at-risk groups.

Eating a lot of fresh fruit may be better for you than eating a lot of sweets but it still contains a high amount of sugar and for those at risk of overweight and obesity has to be consumed with caution. This is exacerbated by the fact some consumers almost regard one of the five a day as a 'free hit', including such foods in their diet but not cutting down on other less healthy foods. 

Some suggest these campaigns should focus on 'swapping' rather than consuming. The fact the 'five-a-day' campaign in the UK has not done this could be seen as a failing, though it should be noted the parallel Smart Swap campaign within the Change4Life programme does.

The question of giving equal prominence to fruit and vegetables is particularly pertinent in light of the direction the food/health debate has taken very recently. The launch of the Action on Sugar campaign at the start of the year and the consultation on sugar intake initiated by the World Health Organization underlines how the focus is now firmly on sugar and on obesity.

It should be noted the five-a-day campaign in the UK and others like it elsewhere were never anti-obesity measures. However, now the focus of health campaigners is so firmly on sugar it could be its failure to differentiate sufficiently between fruits and vegetables will be seen as a more troubling weakness. Furthermore, food companies may find themselves subject to increasing criticism for marketing products with high levels of added sugar under the 'five-a-day' banner.