'Superfoods': A healthy way to eat?
A type of nutrient-rich broccoli can boost your metabolism, scientists believe. But are such "superfoods" a healthy way to eat?
Fancy eating a stem cell beef burger, with some genetically modified rice? Perhaps with some specially bred broccoli that can "retune" your metabolism?
It's not outlandish, each has recently been announced by food technologists and scientists working to modify and improve the food we eat.
The burger, grown in the lab rather than grown as part of a living animal, is designed as a way to provide protein-rich meat while avoiding the killing of livestock. The broccoli, a recently published study shows, contains an active compound that helps human cells work more efficiently. While the release of a rice in the Philippines, genetically modified to contain more vitamin A to boost our immune systems and avoid blindness, edges closer.
Boost your nutrients:
Modifying our food isn't itself new. Since the dawn of agriculture, we've bred crops to be larger, sweeter, yield more, or resist disease.
But that trend continues with greater urgency. Many of the world's soils are losing nutrients, and with the rise of monocultures, and loss of fruit and vegetable varieties, our fresh food contains less 'goodness' than 50 years ago, some experts say.
So scientists are looking to artificially boost the amount of nutrients in our food, particularly to help feed millions of malnourished people in developing countries.
A related trend is also emerging; foods in developed countries including the UK are also increasingly being modified and fortified. But they are marketed and sold to us to boost our health, rather than provide a basic level of nutrition.
The hope is that one day such foods might even mitigate the impact of certain cancers.Manipulating micronutrients
For plants, there are different ways to manipulate the nutrients they contain. One powerful method is selective breeding, seeking out varieties and strains that take up more nutrients from the soil, for example.
- Means searching for a specific characteristics within varieties of crop and then inter-breeding them.
- Scientists use: Seed banks of older varieties
- Mutagenesis - chemical or physical induction of genetic mutations to create new variation
- Wide crosses: interbreeding between cultivated species and closely related species
Genetic modification (GM):
- Used to transfer a single gene or several genes from one species into another
- Scientists can control when a gene is turned on in a plant's development and where it is expressed to change the characteristics of a crop
Most people don't eat enough of the micronutrient selenium, which helps our cells grow.
So scientists are trying to boost the selenium content in wheat by producing varieties that harvest it more efficiently.
Around the world, billions of people are deficient in other vitamins or minerals. About two billion people are deficient in iodine, and two billion anaemic due to a lack of iron. A quarter of people are at risk of not getting enough zinc, which is vital for growth, while hundreds of thousands of children go blind each year due to a lack of vitamin A.
In China, scientists are attempting to fortify ten different vegetables with iodine, as adding iodine to dietary salt isn't contributing enough to people's diets.
Both leaf vegetables and fruit absorb iodine from soil, and a recent study found that adding iodised fertiliser to the soil, in the form of organic algae, boosted iodine levels in vegetables.
Microsoft billionaire and co-founder Bill Gates helps fund HarvestPlus, an international programme attempting to modify food to better feed the poor.
The project has developed an orange sweet potato boosted with vitamin A, and is using conventional breeding to work on six more crops: vitamin A-rich cassava and maize, iron-rich beans and pearl millet, and zinc-rich wheat and rice.
Meanwhile, genetically modified (GM) "Golden Rice" which is grown to produce beta-carotene, is being grown in the Philippines, and scientists are weeks away from submitting it for safety evaluations.
The human body converts beta-carotene into vitamin A, and scientists estimate that one cup of Golden Rice could provide up to 50% of an adult's recommended daily intake.
Some are cautious about modifying food in this way.
There's still "so much we don't know", says Emma Hockridge, head of policy at the Soil Association, a UK-based charity campaigning for organic food and farming.
"Are we able to absorb the extra nutrients? To do so, for some nutrients we need other vitamins and minerals as well, to get them to work. We are not exactly sure what's in (differing vegetables)," she says.
In the developing world, she would like to see a different approach to solving malnutrition. "It is less about getting particular vitamins and minerals but more about access to food or [helping people] grow their own food," she explains.
She points out that someone eating a lot of Golden Rice "may have too much of some vitamins and minerals" and that there are other non-GM crops such as plantain, that contain higher levels of vitamin A.Quick fix?
But modifying food to contain added nutrients and benefits, a process called biofortification, is increasingly popular in developed countries too.
In July, the government launched a £160m Agri-Tech strategy, to encourage more scientific study of foods for the future.
Not enough good stuff:
- Undernutrition: Caused by an inadequate diet, inability to absorb nutrients or excessive loss of nutrients.
- Micronutrient malnutrition: Deficient in one or more vitamins or minerals, such as iron, zinc or Vitamin A.
- Protein-energy Malnutrition (PEM): Inadequate intake of protein leads to stunting, wasting and other childhood conditions. 1 in 4 children are affected
In 2011, one such food went on sale in British supermarkets. Beneforte is a type of broccoli grown in East Anglia.
Scientists bred it to contain three times the normal level of the compound glucoraphanin, which reduces inflammation and inhibits the cell division associated with some early-stage cancers.
A study of the broccoli's impact when eaten has just been published in the American Journal of Clinical Nutrition. It shows eating the fortified broccoli boosts metabolism, and reduces levels of fatty acids and other lipids.
The crop has taken almost 20 years to develop, says project leader Prof Richard Mithen of the Institute of Food Research in Norwich, UK.
"It was cross-bred with a wild species from Sicily - this is plant breeding and is not genetic modification," he says.
"We looked at people who ate Beneforte and their metabolisms worked just a little bit better," he explains. "They were eating four portions a week, of 100 grams a portion for 12 weeks.
"It takes up more sulphur from the soil, to create more glucoraphanin and broccoli is the only plant that produces this compound."
Emma Hockridge of the Soil Association says this broccoli is "mainly aimed at people in the richer West".
Marketing enhanced produce to the masses could mean people increasing look for quick fixes, she fears.
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"There is a danger how people are receiving that message - 'if I eat less broccoli, I can do whatever else I want'," she says.
Though the broccoli is being sold to consumers in two large supermarket chains, Prof Mithen warns it won't solve problems caused by a bad diet.
"People need to have a healthy lifestyle, and include a bit of broccoli, with other fruit and vegetables. I am not advocating it as a 'magic bullet', it won't cure every disease."
He is also keen to explore how to get more folate into our diets, and says a "high folate broccoli could be very interesting, as it would be better than taking supplements, eating it raw".
Ms Hockridge would rather people eat organic produce, which she says is higher in nutrients, a view backed by Katy Mottershead, of the Better Food Organic Food Company in Bristol, UK.
"Courgettes - they come to us in the shop within 24 hours of being picked eight miles away - it doesn't take long to get here, and vegetables after you pick them, the vitamins degrade in them," says Ms Mottershead. "They get to us much quicker than supermarkets get air freight... that means they have more nutrients in them. I certainly feel like they taste better," she adds.
Recent figures show that organic produce sales in the UK are increasing, particularly via home-delivered box schemes.
But researchers at Stanford University in the US have found that eating organic food will not necessarily make you healthier either, although it can cut your exposure to pesticides by 30%.
So the quest for high nutrient "superfoods" looks set to continue. In the meantime, there is one approach to healthy eating that most experts agree on.
Instead of seeking out a single "superfood", it is far healthier to eat a wide variety of foods such as fruits and vegetables, which together, should provide the nutrients we need.