Another Suspect In Ballooning World Health Problem - Microwave Ovens And The Obesity Epidemic

"The first citizens' jury will meet this week to discuss youth and children's issues."
Gordon Brown appoints Tory advisers
Daily Telegraph, 3 September 2007

"A celebrity chef is in hot water with parents after sparking a culinary row by saying that making microwave food for children is an 'act of hate'. Instead Raymond Blanc has argued that parents should take the time to cook their children fresh food.... the National Family and Parenting Institute (NFPI) says knocking convenience food is unfair on busy parents. However Mr Blanc stood by his comments made during his book launch in Manchester earlier this week. 'Such food is full of additives and colourings and has very little taste and very little nutritional value. An act of love is when you cook for your children or your family,' he told Today. However, he accepted that the modern fast pace of life left little time for parents to spend slaving away in the kitchen."
Chef sparks microwave meals row
BBC Online, 3 October 2001

"People have more leisure time than they used to. This is partly due to technological progress. Less time is spent on household chores because of various household durables which we now take for granted. The Family Resources Survey found that in 1998-99, 93 percent of Scottish households had a washing machine and 89 per cent had a deep freeze/freezer. Over three-quarters of Scottish households had a microwave oven and almost a quarter had a dishwasher (Table 10.12)."
Lifestyles
2001 Scottish Social Statistics, Scottish Executive

'Now They Tell Us'
The Full Impact Of Major Changes In Food Culture Can Take Decades To Surface

"Parents have been warned of the effects of food additives on their children's behaviour after new research found a possible link to hyperactivity. A Food Standards Agency (FSA) study of 300 random children found they behaved impulsively and lost concentration after a drink containing additives.... The FAS has met representatives of the UK food industry to talk about the study's implications, but food safety campaigners say it has not gone far enough. Emma Hockridge, of the Soil Association, said the FSA should be taking a leading role in addressing the issue by undertaking initiatives to prevent the development of hyperactive disorders, through new policies to limit food additives. The Food Commission called on food manufacturers to voluntarily remove additives from their products.... Lead researcher Professor Jim Stevenson said the study, published in the Lancet, showed that certain mixtures of artificial food colours, alongside sodium benzoate, a preservative used in ice cream and confectionary, were linked to increases in hyperactivity. He added: 'However, parents should not think that simply taking these additives out of food will prevent hyperactive disorders. We know that many other influences are at work but this at least is one a child can avoid.' He said it was not possible to say which of the ingredients in the additives cocktail affected the children."
Parents warned of additives link
BBC Online, 6 September 2007

"It is more than 30 years since an American scientist, Ben Feingold, first suggested that artificial food colours and other additives caused overactive, impulsive and inattentive behaviour in children; this sort of hyperactivity is known to be a marker for later educational difficulties, especially problems with reading, and antisocial behaviour.... Since Feingold's original work, behavioural problems among schoolchildren have risen, as have diagnoses of attention deficit and hyperactivity disorder (see graph).... Experts were asking yesterday why it had taken the authorities so long to act and why they had not gone further to remove the additives from food.... ....The global additives market is worth more than $25bn (Ł12.4bn) a year. It grew by 2.4% a year between 2001 and 2004, when the food industry says it was transforming itself, and is growing rapidly."
After 30 years of debate, fears over children's food confirmed
Guardian, 6 September 2007

BBC Online, 6 June 2007
http://news.bbc.co.uk/1/hi/health/6725775.stm

Did microwaves 'spark' obesity?

Microwaves may be to blame for kick-starting the obesity epidemic, a UK scientist suggests.

Professor Jane Wardle says obesity rates started to rise soon after 1984 - around the time of the rapid spread of microwave ownership.

The mid-1980s also saw the first ready-meals appearing in shops.

It is one of three theories being debated at Cheltenham Science Festival - alongside the rise of the supermarket and the end of the Second World War.

In 1980, 8% of women and 6% of men were classified as obese.

One of the striking changes was there were differences in the speed with which we could prepare a meal as a consequence of the introduction of microwaves
Professor Jane Wardle

By 2004 this had increased to 24% of men and women.

Children are also suffering from increased levels of obesity, with 16% of children aged two to 15 classed as obese in 2003 compared with 10-12% in 1995.

Experts blame diets high in fat and calories combined with reduced levels of physical activity.

It is often reported that previous generations had a higher calorie intake but were much more active and had physically demanding jobs.

Trigger

The three experts taking part in the debate were asked to determine when the nation's waistline began to expand and what the trigger was.

Professor Wardle who is professor of clinical psychology at University College London said: "I looked at the figures showing rates of obesity in the population over many years and it seem very clear it began between 1984 and 1987.

"So then we looked at what changes were going on in the food and activity world at that time and one of the striking changes was there were differences in the speed with which we could prepare a meal as a consequence of the introduction of microwaves."

She added that food also became cheaper and ready meals began to appear on supermarket shelves.

"I'm not trying to demonise the microwave but it was emblematic of a change that took place in the 1980s in terms of the availability of food - a real change in the disincentives for eating."

Also taking part in the debate is Professor Tim Lang, professor of food policy at City University in London argues that the introduction of the supermarket is to blame.

"Co-op introduced the supermarket retail format to Britain, heralding the late 20th century food revolution in which prices have tumbled, car use rocketed, physical activity plummeted and the NHS was born which picks up the pieces."

Professor Ken Fox, professor of exercise and health science at the University of Bristol says the current obesity epidemic can be tracked back to 1945 and the end of the Second World War.

"The end of the war saw technology starting to replace physical effort in both work and leisure."

Dr David Haslam, clinical director of the National Obesity Forum said all the theories could have contributed to rising levels of obesity and there was no one cause.

"Microwaves are a double-edged sword because they are also a very healthy way of cooking food and supermarkets sell healthy food if people choose to buy it."

He said the end of the Second World War could be important because of the end of rationing.

"We're the only generation where there's never been a shortage of food, so that's a major thing."

Durable goods	Percentage of Scottish households with selected durable goods
Durable goods	1980-81	1985-86	1990-91	1993-95	1998-99⁽¹⁾
Washing machine	83	87	91	93	93
Dishwasher	3	5	10	15	22
Deep freeze/freezer	39	59	76	83	89
Home computer	. .	13	17	21	27
Video	. .	35	64	76	85
Microwave oven	*. .*	*. .*	47	64	78
Compact disc player	. .	. .	. .	43	67
Satellite dish	. .	. .	. .	. .	26
2001 Scottish Social Statistics, Scottish Executive

"To clarify neuronal disturbance in the hypothalamus reflecting the development of obesity in ventromedial hypothalamic nucleus (VMH)-lesioned rats, we investigated the contents of neurotransmitters in the hypothalamus after pretreatment by microwave irradiation, contents of neurotransmitter metabolites in third ventricle fluid and catecholamine contents in the adrenal gland..... These results indicate that a disturbance of NE and DA neurons in the hypothalamus is involved in the development of VMH lesion-induced obesity. In addition, an increment of the activities of NE and DA systems in the central nervous system as a whole and some irregularity in the sympatho-adrenal system might contribute to VMH obesity."
Aspects of hypothalamic neuronal systems in VMH lesion-induced obese rats
Journal Of The Autonomic Nervous System, 1994 Aug; 48(3):213-9

Technical Standards Set A Limit For Microwave Oven Radiation Leakage
Properly Constructed And Maintained Ovens Should Not Leak High Levels Of Microwave Radiation
But How Many People Get Their Ovens Regularly Tested For Leakage?

"If we use our microwave oven for longer than about 30 seconds, our car's alarm goes off. Why? The car is at least 20 metres away through two walls. The inside of the microwave is a little corroded and the car has a remote central locking/alarm system. Certain car alarms, such as those fitted to recent Mazda 6, Toyota Rav4 and Mitsubishi Shogun models, transmit a continuous signal at 2.45 gigahertz at powers of up to 500 milliwatts. The microwaves are picked up by sensors inside the vehicle, which detect changes in intensity to signal the presence of intruders. Microwave ovens also operate at 2.45 GHz. While the power radiated within the oven is typically in the range 600 to 800 watts, the amount radiated outside the appliance will typically be less than a watt. When your oven is in operation, the microwaves reaching your car may be powerful enough to trigger the sensors inside it, which the alarm system interprets as a disturbance within the vehicle. It is possible to set a car alarm so that the internal signal generator is disabled. You might also want to have your microwave oven serviced in case there is a serious leak of radiation. If your microwave has damaged shielding the radiated power could be higher than the values above."
Alarming microwave
New Scientist, 3 February 2007

"All ovens must have a label stating that they meet the safety standard. In addition, FDA requires that all ovens have a label explaining precautions for use. This requirement may be dropped if the manufacturer has proven that the oven will not exceed the allowable leakage limit even if used under the conditions cautioned against on the label. To make sure the standard is met, FDA tests microwave ovens in commercial establishments, dealer and distributor premises, manufacturing plants, and its own laboratories. FDA also evaluates manufacturers' radiation testing and quality control programs. Although FDA believes the standard assures that microwave ovens do not present any radiation hazard, the Agency continues to reassess its adequacy as new information becomes available. Much research is under way on microwaves and how they might affect the human body. It is known that microwave radiation can heat body tissue the same way it heats food. Exposure to high levels of microwaves can cause a painful burn. The lens of the eye is particularly sensitive to intense heat, and exposure to high levels of microwaves can cause cataracts. Likewise, the testes are very sensitive to changes in temperature. Accidental exposure to high levels of microwave energy can alter or kill sperm, producing temporary sterility. But these types of injuries - burns, cataracts, temporary sterility - can only be caused by exposure to large amounts of microwave radiation, much more than the 5mW limit for microwave oven leakage. Less is known about what happens to people exposed to low levels of microwaves. Controlled, long-term studies involving large numbers of people have not been conducted to assess the impact of low level microwave energy on humans. Much research has been done with experimental animals, but it is difficult to translate the effects of microwaves on animals to possible effects on humans. For one thing, there are differences in the way animals and humans absorb microwaves. For another, experimental conditions can't exactly simulate the conditions under which people use microwave ovens. However, these studies do help us better understand the possible effects of radiation. The fact that many scientific questions about exposure to low-levels of microwaves are not yet answered require FDA to continue to enforcement of radiation protection requirements.... There is little cause for concern about excess microwaves leaking from ovens unless the door hinges, latch, or seals are damaged. In FDA's experience, most ovens tested show little or no detectable microwave leakage. If there is some problem and you believe your oven might be leaking excessive microwaves, contact the oven manufacturer, a microwave oven service organization, your state health department, or the nearest FDA office. A word of caution about the microwave testing devices being sold to consumers: FDA has tested a number of these devices and found them generally inaccurate and unreliable. If used, they should be relied on only for a very approximate reading. The sophisticated testing devices used by public health authorities to measure oven leakage are far more accurate and are periodically tested and calibrated."
Microwave Oven Radiation
United States Food And Drug Administration, 14 July 2006

"When used according to manufacturers' instructions, microwave ovens are safe and convenient for heating and cooking a variety of foods. However, several precautions need to be taken, specifically with regards to potential exposure to microwaves. The design of microwave ovens ensures that the microwaves are contained within the oven and can only be present when the oven is switched on and the door is shut. Leakage around and through the glass door is limited by design to a level well below that recommended by international standards. However, microwave leakage could still occur around damaged, dirty or modified microwave ovens. It is therefore important that the oven is maintained in good condition. Users should check that the door closes properly and that the safety interlock devices, fitted to the door to prevent microwaves from being generated while it is open, work correctly. The door seals should be kept clean and there should be no visible signs of damage to the seals or the outer casing of the oven."
Electromagnetic fields & public health: Microwave ovens
World Health Organisation Fact Sheet, February 2005

"Microwave ovens are being used increasingly for industrial purposes, for catering and in the home. They are more economical than conventional ovens - and have many other advantages too. The microwaves penetrate about half to two inches into the food. However, that the electromagnetic field intensities employed are potentially dangerous and precautions are essential to limit any leakage to a biologically safe value (less than l0mW/cm2). To prove and demonstrate the safety effectiveness of the design and manufacture of microwave ovens, and to check that this effectiveness is maintained, periodical checks with a suitable electromagnetic leakage monitor are recommended. The Department has microwave leakage detector available specifically for this purpose. A simple hand-held instrument, it enables checks to be made in situ at the door and inspection cover seals, oven cavities and from the unit used to generate the microwave power. It is important you regularly check the microwave seals to prevent a build up of dirt which may prevent the door closing properly."
Microwave Leakage Detection
States of Jersey, 2007