Salt, of course, is not alcohol. We do not get physically addicted to it. However, it silently wreaks havoc throughout the body by increasing blood pressure, with the consequent risk of disability, or even death, by stroke. And that’s just the start of it. Every day, on average, we eat our way through about eight times more salt than we actually need. These excesses leach calcium from the bones, making them thinner and putting them at greater risk of fracture. Eating too much salt can also aggravate asthma, exacerbate PMT, put stress on the kidneys and increase the risk of stomach cancer.

Personally, I love salt, and the knowledge that eating a lot of salt could lead to a stroke in the distant future hadn’t stopped me adding it liberally. But when Graham MacGregor, professor of cardiovascular medicine at St George’s Hospital in London, told me that lowering my intake could lead to an instant 3lb (1.4kg) reduction in weight, I took notice. Shameful, but true.

This is how MacGregor’s theory works. When we eat excess salt, our bodies hold on to extra water to dilute its presence. This causes the body to hang on to as much as 2.5 pints (1.5 litres) of fluid, which causes the weight gain. According to MacGregor, switching to a low-salt diet will stop fluid retention and therefore result in weight loss.

It is rare to see instant results when making dietary changes, but according to experts, bloating and swollen ankles can literally “deflate” within a matter of days when salt intake is reduced. It can also be particularly beneficial if you are hostage to your monthly cycle, when bloating can strain waistbands to breaking point. As MacGregor says: “Exactly the same principles apply when women swell up during their menstrual cycle. A reduced salt intake can often relieve symptoms dramatically.”

To reap these benefits, it’s important to know how much salt you need, and then get real about how much unnecessary salt you are unwittingly eating. There is no question that salt is essential to your health; for example, it is required to keep muscles and nerves working smoothly, as well as for a myriad other duties. But your body can do this with just 1-2g a day. Unfortunately, the average British adult consumes much more than that.

Somewhat alarmingly, an apparently healthy-sounding day’s menu of a bowl of bran flakes, a slice of wholemeal bread and a glass of orange juice for breakfast; low-fat crisps and an apple mid-morning; soup and sushi at lunch; a low-fat flapjack and smoothie in the afternoon; and a “good for you” style ready-made lasagne for supper gives a whacking 13g of salt. Substitute a few of these options with fast junk food and the figure soars further — some 16g of salt a day is normal for many of us.

The Food Standards Agency has set a daily target for salt consumption of 6g a day. This is between what we actually need (1-2g) and what we actually eat (up to 16g), and it is a good starting point. But if you are serious about sorting out your bloated tummy and swollen legs, not to mention preventing your bones from crumbling prematurely, protecting your kidneys, lowering the risk of asthma attacks and preventing stomach cancer, then aiming for 3g, and no higher, is probably the best bet, says MacGregor.

The first step is to take a serious look at the amount and types of processed foods you consume, since they form the lion’s share of most people’s meals and snacks and contribute to at least 75% of daily salt intake.

Manufacturers are reducing the salt content in bread, breakfast cereals and soups, but even the lower-salt versions — along with fast food and savoury snacks — will still supply the bulk of your salt intake. If you choose carefully, however, you can eat a low-salt diet without subjecting yourself to a regime of brown rice and lentils for ever. Subtle swaps can help to reduce salt while maintaining a fast-track, taste-packed life.

Take the healthy day already mentioned. Swapping from a bowl of fruit-and-fibre-style cereal to fruit-and-nut-filled muesli, which is naturally virtually salt-free, immediately removes almost 1g of salt at breakfast. A juicy, plump peach with a creamy Greek yoghurt mid-morning instead of low-fat crisps loses another 0.5g of salt. A ready-made salmon niçoise salad instead of the soup and sushi saves 5.5g, while a small 20g bar of Green & Black’s chocolate instead of a low-fat flapjack saves another 1g (and, incidentally, 300 calories).

Having a simple dinner of grilled chicken with a tomato, basil and olive sauce, soft noodles and a host of your favourite vegetables (both noodles and vegetables cooked without added salt) saves a further 3g compared to the ready-made lasagne. The day’s total comes out at just 3g of salt, and is far from bland or boring.

Although the initial switch to a lower-salt diet takes determination, you can still indulge your natural desire for delicious food — you just have to be clever with ingredients. For instance, a little sourness from lime or lemon juice in a stir-fry will emphasise saltiness and reduce the amount of salt required. So, too, does learning to make the most of foods containing glutamate, which can dramatically enhance the flavour of dishes. Glutamate is a type of amino acid that is naturally present in tomatoes, parmesan cheese, anchovies and seaweed. In Japan, glutamate is known as umami, or the “fifth taste”. Cooking with glutamate-rich foods means, for example, that you can cook pasta in unsalted water — adding parmesan will give enough saltiness to the finished dish to ensure it still tastes delicious.

Getting clever in the kitchen to help you get back in touch with your taste buds is a crucial part of any salt-reduction campaign. Combine this with some diligent label reading, and within weeks, you can be well entrenched in a lifestyle that’s lower in salt, yet still packed with flavour.

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