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We have probably now all heard of the famous ‘5 a day’, but ask anybody what a portion of fruit or vegetables is and the response given most often is an apple, or less frequently a pear or an orange. It is an obvious, handy answer to the portion issue and works particularly well for everyday fruits we all know and love.
But what about other fruits and veggies which are not so handy in size, how do we measure exactly what a portion is?
Well the simple answer is that we do not have to measure an exact portion, the portion argument can be used as a guide – it appears to work well for handy sized fruits, but we take the meaning far too literally with “I need to eat my 5 a day!” The truth is that 5 a day portion size does actually differ from fruit to vegetables.
In actual fact that five-a-day is a recommended minimum. So who’s recommendation is it and how did this figure materialise out of the ether?
Well for that we need to find out where that recommendation first appeared – and the answer lies in an organization within the World Health Organization – The International Agency for Research on Cancer.
On the 20 June 2001, The International Agency for Research on Cancer media centre released the first results of the EPIC Study into cancer and nutrition – a mammoth 10 year study of over 500,000 participants in 10 European countries (hence the name: European Prospective Investigation into Cancer and Nutrition (EPIC)).
The press release (No 135) gave an indication that fruit and vegetable consumption was protective towards some cancers, particularly those of the colon, rectum and upper aerodigestive tract.
This may not have been new – smaller studies had found similar results in the past, but the Agency quantified for the first time the protective effect of fruit and vegetable consumption. The press release stated:
“A daily consumption of approximately 500g or more is sufficient to decrease by 50% the incidence of cancers of the upper aerodigestive tract.”
There were other results given in the press release particularly relating to the disastrous effects of tobacco and excess alcohol, the contrasting results for preserved meats and red meats, and the protective effect of fish.
In a later press release (no 144; 12 Mar 2003) which followed, the scientists stated that:
“approximately one in ten cancers in western populations are due to an insufficient intake of fruits and vegetables.”
On the flipside, in 2005, the agency further reported that they found no link between the consumption of fruit and vegetables and the risk of breast cancer (press release no 157, dated 12 January 2005). Whilst this was a disappointing observation, one of the lead researchers Dr Elio Riboli stated:
“Although these findings may be disappointing, there are indications that consumption of fruits and vegetables may be protective for cancers of the mouth, pharynx, larynx, stomach and possibly colorectum and lung. Furthermore, fruit and vegetable consumption has been shown to lower blood pressure and the risk of cardiovascular disease, therefore there are good reasons to recommend eating plenty of fruit and vegetables”.
It is from the extensive research leading to these initial press releases that we are encouraged to eat that 5 a day minimum.
If we look back at that last comment from the 2005 press release, we can see that as well as research showing that fruit and vegetable consumption was beneficial for prevention of certain types of cancer, other non-communicable diseases (NCD) such as heart disease could also be prevented with adequate consumption of fruits and veggies.
To put some numbers on those NCD levels, according to The World Health Report 2002 published by The World Health Organization (WHO), low fruit and vegetable intake is estimated to cause about 19% of gastrointestinal cancers, 31% of ischaemic heart disease and 11% of stroke cases worldwide. Overall, 2.7 million deaths each year are attributable to low fruit and vegetable intake.
In response to those numbers from the EPIC study and further studies into other NCD’s, WHO began their global campaign to promote the consumption of fruit and vegetables for health.
In 2003, a joint taskforce of experts from the WHO and The Food and Agriculture Organization of the United Nations (FAO) published a report which recommended a minimum intake of 400g per day of fruits and veggies for the prevention of chronic diseases such as cancer, heart disease, obesity and diabetes.
The report emphasized the minimum of 400g per day, noting that this is a minimum, not a target.
Other noteworthy points are that this is excluding potatoes and other starchy tubers and that a variety of fresh is “best”.
And so it was from this report (WHO Technical Report Series, No. 916) that the recommendation of a minimum of 400g (broken down into 5 portions of 80g each) per day came into being.
In practice the 80g portion size was used as an “average” value. A typical portion of fruit is often larger than this (for example an average apple is about 130 - 150g) and a typical vegetable serving is frequently smaller (a tablespoon of cooked vegetables is around 20 - 25g, so 3 tablespoons is an advisable vegetable serving), but bear in mind that the origin of the recommendation is for a minimum of 400g and that is the cornerstone of the advice.
So when you are wondering about your 5-a-day, fear not about the exact size of your portions, just try to include as much and as broad a range of fruit and veggies in your diet as you can. Studies have shown that frequency of intake may be just as important as exact portion sizes.
One important point to bear in mind - dried fruit was once fresh and as such weighed far more than it does dry. A dried fig, for example, will only weigh around 10g, but a fresh fig will weigh around 40g. Apricots are similar, so for dried fruit assume a 'wet' weight.
Remember that initial research published in the press release, “A daily consumption of approximately 500g or more is sufficient to decrease by 50% the incidence of cancers of the upper aerodigestive tract.”. Note that it does not eliminate the risks, it is simply an amount by weight which reduces the risks by a specific percentage – eat more and you’ll possibly reduce your risks further still – eat less and your protection from cancer and other NCD’s may be reduced.
As a final note, please make choices that you enjoy and don’t get swayed into eating the latest fad food of the year based on an overpriced, overhyped scientific wonderberry from the outer reaches of Mongolia or flab fighting fruits from the deepest jungles of South America – they are just not necessary for a healthy diet.
Yes, we may eat fruits and vegetables grown in all parts of the world these days, but they are not overpriced based upon overmarketed reputedly miraculous effects, they are priced based upon the required growing conditions and the supply and demand for out of season fruits and vegetables – and that is a different story.
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