Hello Cruel World
Thursday, September 16, 2004
RE: HBP some good stuff
Sent: Thursday, 16 September 2004 11:37 AM
To: C; M
Subject: BHP some good stuff
attached here is an article from the UK Guardian on the relationship between salt and high blood pressure. It is easily the best "plain
English" article on the subject that I have ever read. It strikes me as worrying that I have had HBP for quite a few years and got the feeling when reading this that I finally understood what it was all about. I hope that you find it useful.
Against the grain
Health campaigners say it is implicated in tens of thousands of strokes and heart attacks each year. Now the government wants to persuade us all to eat less of it. But is salt really as bad for us as the health lobby insists? Sarah Boseley and Tim Radford investigate
Wednesday September 15, 2004
Civilisation is built on salt. The discovery of its power to preserve food enabled wandering tribes to put down roots. Men and women could hunt and gather today and eat tomorrow. A life that was no longer hand to mouth allowed time to sit and think. Salt became as precious as any metal, was traded between nations and offered as gifts. Its influence lingers in our linguistic value judgments: a good man is the salt of the earth and worth his salt, but a social inferior sits below it.
But the white crystals have lost their magic. "It wasn't a gift for civilisation. It was a poison," says Graham MacGregor, professor of
cardiovascular medicine and the one man who has probably done more than any other to shake our confidence in a substance traditionally offered
with bread as a sign of friendship to strangers.
MacGregor is chairman of CASH (Consensus Action on Salt and Health) and is this week savouring the sweet taste of success. Ten years after
he and fellow experts on blood pressure began pressing for limits on the amount of salt we eat, which they say is implicated in 120,000 heart attack deaths a year in the UK, the Food Standards Authority has launched a £4M campaign to persuade us to eat less of it — and manufacturers to cut the sackfuls they pour into our processed foods.
But it isn't the salt on your table that does the damage — it's the salt in your lasagne and, more alarmingly, your bread. The FSA says that 75% of our salt comes from processed foods, and that an adult consumes 9.5g a day, though we don't need more than 6g. Baked beans, breakfast cereals, pizza, soup and cooking sauces tend to be salt-lavish, but so are some sweet foods, such as biscuits and hot chocolate.
Why does our food contain so much salt? Not only because manufacturers found it made their products taste more interesting, but also because it binds in water, thus cheaply adding "texture" or bulk. It also makes you thirsty — another knock-on effect for the food and drink industry.
MacGregor argues that thousands of lives could be saved by cutting the salt content of processed foods by 10-20%. "If salt intake was reduced to 6g a day, it would prevent 70,000 heart attacks per year, 35,000 of which are fatal. It is as big an improvement as when they put drains into London," he says.
Unusually for a bunch of scientists, CASH is extremely media-savvy. It was naming and shaming high-salt foods, lambasting individual
manufacturers and barbecuing supermarkets long before health minister Melanie Johnson got in on the act. This month it scored a direct hit on
Sainsbury's, fingering the company's "Be good to yourself" flakes and orchard fruits as one of "the UK's saltiest foods". One 50g portion
contained 1.84g of salt, it said. Sainsbury's immediately pulled the product off the shelves.
Back in 1994, the government's advisory Committee on Medical Aspects of Food and Nutrition (known as COMA) recommended a model diet for the
UK, including a reduction to 6g of salt a day. The food industry obtained a leaked draft and four heavyweight food manufacturers,
Cadbury Schweppes, Tate and Lyle, United Biscuits and Mars demanded a meeting with the department of health. They did not get the reassurance
they wanted. That same year, United Biscuits and Tate and Lyle cut their contributions to the Tory party.
MacGregor is convinced that this contributed to the government's rejection of the recommended salt level which has now been espoused by the FSA. "That really infuriated us — that for a few thousand pounds, the health policy of the UK could be altered," he says.
CASH was formed in 1996 to press the case through the media instead of polite government channels. It has worked better than they imagined.
"If you had said to me in 1996 that in 2004 the FSA would launch a £4M campaign about the dangers of salt, I'd have said you were joking, says MacGregor. It took almost 40 years to get serious action on smoking, he points out.
As any school child knows, salt is scientifically known as sodium chloride. It's a simple combination of two molecules, easily extracted
from water. Salt's primitive appeal must have to do with its bodily familiarity - our tears are salty; our blood is salty. But the question
is how much we need of it. Chimpanzees and orang-utans get their sodium from plants they eat, not the salt cellar, and they have perfect blood
pressure of around 90 over 70. High blood pressure, increasingly common in the UK where it rises steadily with age, is responsible for half the heart attacks and strokes that kill people here - 120,000 out of 240,000 a year.
MacGregor claims there is virtually no scientific dispute in the UK over the link between salt, high blood pressure and heart attacks.
Excess salt, says MacGregor, leads to water retention. People who eat too much salt could have a litre and a half of extra fluid sloshing
around in their veins, he says. That means there is more blood for the heart to pump, and the blood pressure goes up.
The question of how much is too much, however, seems to vary from person to person. It's quite possible that some of us can eat salt without living dangerously. Five years ago a team from the University of Utah school of medicine (in Salt Lake City, of course) identified three variations in a bit of human machinery called the angiotensinogen gene. High levels of a hormone produced by this gene also correlated with high blood pressure. They reported in 1998 that variants in the gene made some people much more sensitive to salt. So for some, a low salt diet had a significant effect on blood pressure.
There is more than one cause of high blood pressure. But most people in the field believe that maybe one third of all hypertension sufferers
are reacting to the buildup of sodium. Yet some humans feel they need salt, and some feel the need for salty food at all times. Six years ago
Ilene Bernstein, of the University of Washington, proposed that babies might arrive with a taste for salt implanted at birth.
It depended, she and colleagues claimed, on just how nauseous and uncomfortable their mothers felt during early pregnancy. They reported in 1998 that adult children of mothers who had experienced morning sickness to conspicuous levels were also very keen on salty snack foods. Babies at 16 weeks old were more likely to show a fondness for salty water if they had previously sent their mothers-to-be retching to the bathroom. Her guess was that dehydration linked with vomiting might have something to do with a fondness for salt.
"Fluid depletion in the mother triggers the hormonal system in the blood and kidneys to restore the normal fluid level," said Bernstein. "We don't know if these hormones cross the placental barrier and affect the baby or if dehydration causes the baby to release its own hormones to restore fluid balance. These hormones can have powerful effects on the brain."
Such claims are contentious. But they do illustrate the complex link between salt and the functioning of the human machinery. Some babies
show a distinct response to (very slightly) salty tastes within three days of birth, the response being strongest in those babies who have at
least one grandparent with a history of hypertension, according to the journal 'Hypertension' in 2002. A team from Mount Auburn Hospital in
Cambridge Massachusetts tested 283 babies in their sucking response to the taste of salt and sugar. The 67 babies that seemed to like salt most already had, at three days, higher blood pressure levels than those who seemed to object to the taste.
Such research seems to suggest that appetite, inheritance and environment all play a part in the link between salt and hypertension.
But this is not saying very much: appetite, inheritance and environment play a role in practically everything. Nobody is yet prepared to suggest that a warm response to a hint of the flavour of salt is really an indicator of some future cardiovascular troubles to come.
Salt manufacturers are unsurprisingly unhappy at the turn of events in the UK, in spite of the fact that most of what they produce ends up on the roads rather than in our baked beans. "The biggest problem we have is that the deer on the roads lick up the salt — they like it just as we do," says Peter Sherratt, general secretary of the Salt Manufacturers' Association.
While the food manufacturers agree to salt reductions here and there — although not as comprehensively as the FSA and CASH want — Sherratt insists much of the science is nonsense." A heck of a lot of literature says the government is wrong."
He cites two documents that have come out within recent months. The national diet and nutrition survey commissioned by the government says
salt has no effect on the blood pressure of healthy people, while the National Institute for Clinical Excellence says that people with high
blood pressure should be on drugs to control it. "I don't understand where salt comes into the equation," he says. "There is no problem with
a healthy person, and an unhealthy person should be on drugs."
If some of us are more susceptible to salt-related damage than others, maybe there is an element of sense in that, but that's not how public
health strategies work. We all have to eat less salt because we don't know who the lucky people are who can eat crisps with impunity. And if
we won't even notice a small cut in our salt intake, then it's hard to see the problem for anybody except a salt manufacturer — or a processed food company that has to have another think about how to make its pizzas taste good.
I heard an explanation about how smoking affected blood pressure & thereby a bunch of other things just recently too.
Has to do, apart from any possible effect of nicotine or other pharmacologically active ingredients, with carbon monoxide. CO "locks" onto the haemoglobin where O2 and CO2 bind more loosely. Thus it takes red blood cells out of use, though they are still circulating. Your body has to make more RBC to replace the lost capacity. This makes the blood thicker (more viscous), so your heart has to work harder, more wear & tear on the heart & blood vessels, more likelihood of clots (with same side-effects as DVT),also tends to damage one's kidneys, which have a fine tubing filtering system, through the viscosity & higher pressure.
NOTE: This would apply to pretty much any smoke inhalation, not just tobacco. Deaths by smoke inhalation in fires are mostly CO overload; you lose usable haemoglobin faster than you can replace it, then can't absorb enough oxygen from air to support vital functions. (Breathing pure O2 to recover might work unless you've lost just too much capacity. I guess a blood transfusion -- after draining out some of the bright red monoxided stuff -- might be treatment. Leads one to wonder what would happen to avampire drinking the bad stuff: goes down to mortuary to find fresh corpses, picks wrong one?)
JOYS OF DIGITAL TELEVISION: The STB 'crashed' again t'other night. It froze on a half-pixellated image on Channel 9, then refused to be changed from there. I tested the timer, and it recorded the (broken-up) sound from Channel 9, still stuck on the same image.
Re-set the box, and for a while the sound didn't come up, but reset again & seems to be all OK, **EXCEPT** for Channel 9. Am now getting [Loss of signal] box on all of their channels (ie, including EPG & multiview). Other channels seem to be OK. Just what is it about TCN 9? Anyway, the non-STB non-ABC reception just on TV is OK, so am sticking to that -- there are very few things indeed on 9 I'd be recording until they bring West Wing back. Have caught a couple of episodes of Six Feet Under, but at the moment it's a bit character-based, so if you haven't got to know them already, it's not as likely to draw one in.
ALSO: Looked at the Amazon customer comments on West Wing DVDs, and Region 1 versions have commentaries on them. The UK people are complaining Region 2 doesn't. Have a guess if Region 4 does. Uh-huh.
INTERESTINGLY, in the Product Details or Technical Details section of the Amazon description of the different season's (seasons') box sets, they do NOT have a list of the episodes included (if you were looking for a particular one w/o knowing which season it was), NOR ANY LIST OF 'EXTRAS'. Thus, you wouldn't know if the extras in different DVD Regions were different.
I WONDER IF THERE IS THE SAME LACK OF INFORMATION ABOUT OTHER DVDS?
I think I can remember some other online retail outlets having more information about what's included on DVDs.
PS: It's nice in the article you sent, above, that they spelt 'barbecued' correctly.
ALP tax policy
Tue, 07 Sep 2004
Interview with Mark Colvin, ABC Radio's PM
Ricky Swallow, Artist
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