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Today, 65 m Americans suffer from hypertension, and 59 m more have pre-hypertension. In other words, over 40 % of the
population is at risk. Halving the amount of salt in the diet, says the AMA, would save 150,000 lives annually in the United States
alone. That’s five times more than the number of people killed on the road each year.
But unlike trans-fat, removing salt from the diet altogether would be most unwise. Sodium is one of the body’s four essential
electrolytes (along with potassium, calcium and magnesium). It helps maintain the right balance of fluids in the body, and allows the
brain to transmit messages and the muscles to contract and relax.
But if your kidneys can’t regulate the amount of sodium in the body properly, it builds up in the blood. Because sodium attracts and
stores water, the volume of blood then increases. That puts extra pressure on the heart and the arteries. And if the omens are against you,
the result is cardiovascular disease.
No matter how you look at the data, there’s no question Americans consume way too much sodium. With a few exceptions, most
people need no more than 0.5 grams a day – and seriously shouldn’t take more than 2.3 grams (the amount of sodium in a teaspoon of
salt). If you’re black, middle-aged or older, or have high blood pressure, chronic kidney disease or diabetes, you should restrict your
daily intake to 1.5 grams at most.
Yet, with a pinch here and a dash there – plus dollops of the stuff in processed food and restaurant fare – most of us unwittingly
ingest between 3 and 4 grams of sodium every day, with some determined folk racking up 20 grams or more.
The trouble is that salt makes food tasty. Because we need it to survive, we seem to be genetically programmed to like it. Taste
tests show people from all cultures, even those that have low-salt diets, opt for saltier items when given the choice.
No wonder salt is used to flavour or preserve so many of our favourite dishes – from potato chips and snacks to fish, meat, dairy
products, canned vegetables, pickles and bread. A single bagel or a slice of pizza will supply the body with all the sodium it needs for a
day. A frozen TV dinner or a meal from a fast-food joint will dose you with ten times the necessary amount.
Losing the taste for salt is difficult, but not impossible. In Britain, for instance, where the average person used to consume 4
grams of sodium daily, the government has pressured food manufacturers into lowering the salt content in some 85 categories of
processed foods. Already progress is being made in reducing the population’s daily intake to no more than 1.6 grams.
The Finns have been at it longer, and chalked up even greater success. Over the past 30 years, they’ve lowered the amount of salt
in their diet by 30 %. In the process, Finland has seen a 10 mm drop in blood pressure nationwide, and a 75 % reduction in
cardiovascular disease in people under 65 years of age, plus a six-year increase in life expectancy.
As in Britain, success has come from clever media campaigns aimed at fostering better eating habits, plus labeling laws that force
food manufacturers to mark their products "high in sodium" if they exceed certain levels.
Could something similar happen in America? Certainly, and it probably wouldn’t take 30 years. Stopping people smoking in
public was a far bigger challenge. The measures changed national habits within a decade – though it took legislation to make it
happen, initially as city ordinances and later as state-wide initiatives.
Interestingly, New York City – which was among the first to ban smoking in restaurants and bars, and the first to pass laws
targeting unhealthy eating habits – isn’t waiting for a new administration in Washington, DC to place salt on some national hit list.
By all accounts, New York is preparing to add permissible sodium levels to its recent ban on artificial trans-fats and its
requirement for calorie counts to be listed on the menus in restaurant chains. Absent some national initiative, San Francisco, Los
Angeles and Seattle won’t be far behind.
One way or another, the betting is that by this time next year salt will be the new trans-fat. And manufacturers will be vying with
one another to provide the lowest figure in the land.
T a s k O n e. Answer the following questions.
1. What speedy decisions will the government need to make after the current presidential campaign?
2. What is a key factor in heart disease and stroke?
3. What do studies done at Indiana University suggest?
4. What do doctors compare two numbers when measuring the pressure of a person’s blood?
5. What does sodium help maintain?
6. Why does sodium build up in the blood?
7. Why do we seem to be genetically programmed to like salt?
8. What has the government pressured food manufacturers into doing in Britain?
9. What is New York preparing to do?
T a s k T w o. Write a brief summary of the article.
A R T I C L E 2. Treatment on a plate.
Oct. 16
th
2008
From
The Economist
print edition
A dietary approach to treating addiction seems worth investigating
PEOPLE are programmed for addiction. Their brains are designed so that actions vital for propagating their genes – such as eating
and having sex – are highly rewarding. Those reward pathways can, however, be subverted by external chemicals (in other words,
drugs) and by certain sorts of behaviour such as gambling.
In recent years, neuroscientists have begun to understand how these reward pathways work and, in particular, the role played by
message-carrying molecules called neurotransmitters. These molecules, notably serotonin, dopamine and gamma-aminobutyric acid
(GABA), hop between nerve cells, carrying signals as they go. Some drugs mimic their actions. Others enhance them. Either way, the
body tends, as a result, to give up making them. At that point the person needs the drug as a substitute for the missing transmitter. In
other words, he is an addict.
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