We eat hundreds of foods throughout our lifetime. All of these foods are made of up chemical compounds - although it sounds less worrying to call them nutrients and non-nutrients. Our individual metabolisms use these chemicals to extract energy and use nutrients to enable our bodies to grow and repair.
The key word here is individual; the subtle variations in our genes mean that we deal with the same nutrient in slightly different ways. The long-term goal of nutrigenomics is to tease out the relationship between each different food and these genetic variations, and ultimately to understand how real foods affect the whole body and its health.
Within nutrigenomics, there is a sub-branch called nutrigenetics. This focuses on how an individual reacts to an individual food. That is determined by the genes that that individual has inherited from their parents, but there are variations, as Professor John Mathers, from Newcastle University explains:
"So you and I differ by maybe 100,000 little changes in our genetic make-up, called polymorphisms. And they make us what we are: taller or shorter, different coloured eyes, different coloured skin and so on. In addition to the very obvious differences, we also differ in how we metabolise foods and how we use those foods and how that influences function and health." No easy task
To get a handle on how many variations are possible, it is estimated that over half of our genes play a role in metabolism. And the total number of polymorphic variations across the world's population is estimated at 10 million. So using ropey induction, that gives us over five million genetic variations to identify.
Just in case you thought this was a simple task, here are a few additional problems to bear in mind. Humans are notoriously difficult to study. They tend to be unreliable about writing down what they have eaten, for all sorts of reasons. This means if you want to know the effects of a food on people, you have to keep them where you can monitor them. There are all sorts of rules and regulations meaning that you can't incarcerate them, although
prisoners have proved quite useful in nutritional studies into the effects of Omega-3 on behaviour.
Humans have different lifestyles so the effect of the food in study has to be measured alongside other factors, such as whether they smoke, exercise, drink alcohol, how old they are, etc. And the scientists have little idea of the relative importance of these many factors.
Personal food plan
There are some examples where we know that eating certain foods can protect us from a variety of age and diet-related diseases. Eating cooked tomato sauces reduces a man's risk of developing prostate cancer. A high folic acid intake reduces the chance of neural defects in the foetus. However, this jigsaw is still in the early stages and most of the pieces are missing.
That hasn't stopped certain companies from capitalising on the scientific principle - you can already buy nutrigenetic kits over the Internet. For a few hundred dollars and a swab of your saliva, you can receive a personal plan of foods to avoid/eat plentifully. Some companies will also provide you with supplements, designed to offset your personal genetic risks. And this is making certain people uneasy.
Genewatch UK, a public interest group, point out that the validity and usefulness of these tests has not been assessed. They are also concerned by what they see as the medicalisation of these genetic risks. And certainly, from food industry's perspective, there isn't much "value-added" profit to be had from getting people to eat fruit and vegetables.
Another of their broader concerns about personalised nutrition is that it promotes a false solution to the current epidemic of diet related disease. But the science is in such early stages that, as far as I can see, it offers no solutions at all. Whilst it is true that we'd all do well to pay attention to current nutritional advice, I don't see this as a reason to stop the scientific investigations. As in so many areas of science, the knowledge isn't dangerous. Lack of regulation over how to apply it may be.
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There are sub-groups of the population where you can make a clear link between diet and health, and one such group are the Dutch famine babies, a group studied by the Amsterdam Medical Centre.
The individuals being studied are now 61 year olds, but they were all unborn children around the time of the Dutch Hunger Winter, a short period of famine towards the end of WWII.
The Netherlands was under Nazi occupation during WWII. Towards the end of the war, in response to resistance, the German administration banned all food transports to the western Netherlands.
By the time the embargo was partially lifted in early November 1944, allowing restricted food transports over water, an unusually harsh winter had already set in. The canals froze over and became impassable for barges. Food stocks in the cities in the western Netherlands rapidly ran out.
The adult rations in cities such as Amsterdam had dropped to below 1000 calories (4,200 kilojoules) a day by the end of November 1944. Over that winter, known as the Hongerwinter ("Hunger winter"), people would walk for hundreds of kilometres to trade valuables for food at farms.
J. Vrouwenfelder from the Hague recalled:
"I queued for hours to get some salted endive or some beans. Always that hunger...And then there was less and less. There remained nothing, not even in the black market. Sugar beets from which we first made syrup and then some kind of cookies from the leftovers. Impossible to eat, but it kept many people alive. Fried tulip bulbs were the last resort."
Famine mode
From September 1944 until early 1945 approximately 30,000 Dutch people starved to death. The German occupiers allowed coordinated air droppings of food by the Royal Air Force over German-occupied Dutch territory in Operation Manna, which saved many lives. The Dutch Famine ended with the liberation of the western Netherlands in May 1945.
By monitoring the people who were malnourished in the womb and comparing them with babies born the year before and after the famine, scientists can see clear increases in certain diseases, such as diabetes.
The babies' genes were switched to "famine mode," where the body, experiencing nutritional deprivation in the womb, expects the food shortage to continue throughout life and switches on the genes to grab every spare nutrient going.
This switch on its own won't make individuals fat - they'd need to overeat as well, but the fact that the famine babies are often fatter adults with a three-fold increase in cardiovascular disease shows the power of the gene-diet interaction.
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Dechenne Rachel,
rdechenne@hotmail.com,
27-11-2006
- UK
Putting Nutrigenomics on the map
What might appear like just another fad has much more implications than you might think. Most of us can't exactly explain what functional food stands for, let alone nutrigenomics! In thousands of laboratories around the world, however, scientists are busy whispering the "N" word with respect and devotion. All that hard work to gratify us with a new generation of allegedly called “functional foods” this time based on our genetic make-up. Currently nutrigenomics proponents argue that, if made available to everybody, it will reduce and ultimately eliminate racial and ethnic disparities resulting from environment-gene interactions, particularly those involving dietary, economic and cultural factors (Center of Excellence in Nutritional Genomics at UC Davis, USA).
“Lets don't bother about putting too much effort into changing our lifestyle and support organic, locally produced, well-balanced food, exercising and rethinking our food habits. That doesn't work anyway.” Very soon a deluge of adverts will say that: "It's the genes fault if we put on weight or get depression etc. All we all have to do is to take a quick blood test and go to the supermarket to buy the corresponding techno-food/drink”. Of course, cheap version will also be available in newly built supermarket owned by Tesco, Wal-Mart and consorts in India, Thailand, China, etc. » This could sound as a pretty good idea, just like the promises to alleviate world starvation with genetically modified crops ten years ago! However, just like the latter, nutrigenomics” honorable goal is far from having any beginning of proof to substantiate it. I am not implying that nutrigenomics is good or bad. As a science it has no other pretension than to push our knowledge of food and diet interactions a little bit further. As the article posted on this blog rightly said: “The knowledge isn’t dangerous. Lack of information over how to apply it may be.”
My concern is that the appetite for control and greed of a few might eventually prevail over a “boring” balanced and precautionary approach that would benefit all. What’s important, I believe, is that a full assessment of the risk/benefit of the technology, including consumers participation, is conducted before deciding of the trajectories of development. As a trained food policy analyst and lawyer, I’ve made my homework and started to document that research examining the social impacts and the balance of risks/benefits of the commercialization of these future products on a global scale are largely overlooked. If the political process is not opened up to take into account alternatives views, including consumers opinions, it may lead to confusing further more public perceptions regarding an healthy diet. It might contribute to further transforming our societies into big hospitals filled with hypochondriacs. Despite this, Governments around the world, lured by this easy way out of the health care nightmare, are investing in food industry to produce the miracle product instead of insuring a sound and fair supply chain. Of course the alternative offered is not an easy one. Moderation is not as sexy as a wonder science, but it is certainly a more realistic approach for consumers. Of science can help but it can’t tackle the roots of MAL-NUTRITION raging in both hemispheres (obesity, anorexia, etc). The inequalities and consumerism illusions caused by government disengagement, bad governance and the triumph of unfettered free trade dogma are certainly not just a matter of finding a new wonder science.
In short, what really concern me is that the current development of this niche science is kept behind closed doors without an appropriate risk assessment of the technology to determine which developments to prioritize based on the necessary evidence-based information.
The current private and public sector research in nutrigenomics, at the EU and the US levels, is heavily aimed at commercial rather than “public health” ends. Where a commercial approach is pursuit, there is very little public research serving to inform about the ethical challenges of future genetically-tailored functional food. Consequently not much is done in term of regulatory benchmarking to protect from misleading health claims and avoid pushing through unneeded commercial applications. It is, therefore, crucial to inform all the stakeholders (regulators, scientists, social scientists and especially the consumers) of the importance of integrating a broad socio-cultural dimension in the technology assessment of nutrigenomics. But as underlined before, the moderation path doesn’t stand a chance while facing the prospect of an ever growing billion $ market in functional food. At the end of the day, it’s all down to us: the consumers. If we don’t use our critical judgment to stop being force fed with illusions that get us fat and ill while starve the rest of the world, than a few billionaires at the top of intangible fortresses “multinational companies” will keep on draining the biosphere of all its blood.
What I am personally planning to do is to extend my investigation started at City University, London, under the supervision of Professor Tim Lang and inspired by my work with Vandana Shiva in India. I am currently putting together a proposal to rise funding with the help of professional fundraiser (pro-bono) here in London. It is, as you might imagine, not the easiest task but as I try to demonstrate here, such work is urgently needed. I will put the information gathered in a format accessible to a wide audience and not only the so-called experts. The work I am intending to do will supply people with enough information to develop their own opinion on what the development of the science behind nutritional genomics will entail for their everyday life. It will also show how our support for functional food (buying power) reverberates in the population of the South. It will, among other, explain how these poor countries are currently graciously providing the human guinea pigs necessary to get the precious genetic data, the core material upon which nutrigenomics knowledge is built, and cheap scientists to develop premium techno food for a handful of “worried-well”.
As stated earlier, my message will revolve around the fact that unhealthy nutrition is a complex problem rooted in inequalities and delusions caused by government disengagement, bad governance and the triumph of unfettered free trade dogma. It is not just a matter of finding a new wonder science. Let’s not be fooled and concentrate our precious resources on what really works!
All the best,
Rachel Dechenne
jasmin,
29-09-2006
- India.
Great article !
I quote an artcle by Sri Swami Sivananda below ;
Three Kinds of Diet
Diet is of three kinds, viz., Sattvic diet, Rajasic diet, and Tamasic diet. In the Bhagavad-Gita, Lord Krishna says to Arjuna: "The food which is dear to each is threefold. The food which increases vitality, energy, vigour, health, and joy and which are delicious, bland, substantial, and agreeable are dear to the pure. The passionate persons desire foods that are bitter, sour, saline, excessively hot, pungent, dry, and burning, and which produce pain, grief, and disease. The food which is stale, tasteless, putrid, rotten, and impure, is dear to the Tamasic".
Milk, barley, wheat, cereals, butter, cheese, tomatoes, honey, dates, fruits, almonds, and sugar-candy are all Sattvic food-stuffs. They render the mind pure and calm and play a very important part in the practices of spiritual aspirants, in the mental development of the student, and in the personality- power of the leaders of mankind. Fish, eggs, meat, salt, chillies, and asafoetida are Rajasic food-stuffs; they excite passion and make the mind restless, unsteady, and uncontrollable. Beef, wine, garlic, onions, and tobacco are Tamasic food-stuffs. They exercise a very unwholesome influence on the human mind and fill it with emotions of anger, darkness, and inertia.
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