While recent trials debunked some established truths about salt, the leader of the research says the findings don’t give us a licence to liberally consume it either, says Peta Bee.
FOR decades the message has been to cut down on the white stuff, to avoid liberally adding salt to our food for the good of our health.
Salty diets have been shown to raise our blood pressure and our risk of diseases from stomach cancer and osteoporosis to kidney disease and vascular dementia. Too much of the white stuff can also exacerbate symptoms of asthma and diabetes.
According to the Food Safety Authority of Ireland (FSAI), food manufacturers have made “significant reductions” in the levels of salt added to the food we buy, but our salt intake is still way too high. The recommended dietary allowance (RDA) is 1.6g/70 mmol sodium (4g salt) per day for adults, yet each adult currently consumes 10g of salt daily, a level the FSAI describes as “well in excess of physiological requirements” and more than double the acceptable upper limit.
“Our body needs about 4 grams of salt each day and an acceptable maximum level is 6 grams or 1 teaspoon of salt per day,” says consultant dietician Paula Mee:
“Many people, especially men, exceed this level of salt intake and eat on average about 9 to 10 grams of salt per day. Children need to eat much smaller amounts of salt. School children should eat less than 4 grams per day and younger children should eat only the minimum amount of salt.”
However, some exeprts now argue that the salt message has been blown out of all proportion. In The Salt Fix: Why The Experts Got It All Wrong and How Eating More Might Save your Life, Dr James DiNicolantonio — a respected US cardiovascular research scientist who is also an associate editor of the British Medical Journal’s Open Heart, published in partnership with the British Cardiovascular Society — argues that most of us don’t need to watch our salt intake at all and, in fact, might be better off consuming more salt than less of it.
It’s easy to forget that some salt — or sodium chloride — is essential for health. It is needed by every cell in the body and required to regulate fluid balance, as well as for nerves and muscles (including those in the heart) to function well. But can it really be the case that everything else we thought we knew about salt was wrong?
“The new findings demonstrate that consuming too little salt is not good either, but the most significant point is that the studies and evidence support our guidelines to lower excessively high salt intake,” says Mee.
Here we delve deeper into the salt debate:
Salt may not make us thirsty
Most of us learn how and why salt makes us thirsty in science lessons at school, that the more salt you consume in food, the greater the urge to drink as your body attempts to maintain its delicate concentrations of salts in the blood.
Yet two recent studies published in the Journal of Clinical Investigation challenged this accepted wisdom. Both trials were led by Jens Titze, a kidney specialist and associate professor of medicine and of molecular physiology and biophysics at Vanderbilt University Medical Centre.
In the first of the investigations, his unusual group of subjects — ten Russian astronauts studied during two simulated space flights to Mars lasting 105 and 205 days — were asked to stick to a diet of varying degrees of saltiness. On the shorter of the two flights, the crew ate a diet containing 12g of salt, double the level recommended as a healthy upper limit for adults in the UK, followed by 28-day cycles of 9g daily salt and then a low-salt diet of 6g per day. They were given a similar intake on the longer flight, but with another 28-day cycle of 12g of daily salt added to the schedule.
Initially, Titze saw that, the more salt in the astronauts’ diets, the greater their volume of urine as they excreted it. Yet, when he looked closer, he unexpectedly found that, the saltier their diet, the less thirsty they had become and the less they drank. It seemed they hadn’t drunk more fluid, as he had expected, but that their bodies produced more water in response to the salty food.
It could help burn calories
In his studies, Titze was also puzzled by the fact the astronauts seemed to be hungrier when eating the diet with most salt, despite the fact their calorie intake was controlled and consistent. Tests of their urine samples revealed the subjects were producing higher levels of glucocorticoid hormones, known to influence immune function but also metabolism.
Intrigued to find out more, Titze carried out a subsequent experiment using laboratory mice. He found that raised levels of hormones triggered the body to break down fat and muscle, freeing excess water for the body to use. The whole process used up energy and, in short, the more salt the mice ate, the more calories they burned up. So pronounced was the effect that the mice gobbled 25% more food just to maintain their body weight when on the saltiest diet. Even he was “surprised” by the results: “I could never have imagined that salt intake might have such a dramatic impact on energy metabolism,” he says. “We had
always focused on blood pressure in research. That was the only thing we could think of that it might affect.”
It might curb cravings
One of the claims made by Dr DiNicolantonio in his book is that too little salt in the diet can lead to cravings for sugar and refined carbs and to weight gain. Titze says the claims and his findings should be taken with, well, a pinch of salt. A lot of people are now suggesting that salt may help you to lose weight, so why not consume more of it?
“I think it is not a good idea, for several reasons,” Titze says. “Firstly, hunger is a very significant reason to flunk a weight reduction programme — and salt seems to make us hungry.
“Secondly, even if successful, what would the weight reduction look like? Glucocorticoids reduce muscle mass, and increase the relative amount of fat. I’m not sure that this is the toned, lean weight loss people are dreaming of.”
But we should still cut down…
Even Titze says his findings are not a green light to use the salt shaker more liberally. For one, the elevated levels of glucocorticoid hormones that seem to accompany a salty diet also contribute to the development of chronic diseases.
“These hormones are associated with increased risk of stroke and cardiovascular disease,” he says. “Not good.”
A lot more research needs to be done before health advisors “rethink the principles of salt metabolism”, Titze says. So, for now, the advice remains to err on the side of caution.
Consultant dietician, Aveen Bannon, says overwhelming evidence points to the healthiest diets being low in salt and high in potassium, a mineral she describes as “the enemy of salt” that is abundant in vegetables.
“Eating a lot of vegetables and some fruit, avoiding adding salt to meals and choosing wholefoods over processed foods are healthy choices,” she says.
“Salt has been linked to high blood pressure in studies and high blood pressure is linked to poor heart health, one of the
biggest killers in Ireland.”
How yoga poses can help with digestion
Alongside mindfulness tips, vegan recipes and juices, Chris James, yoga instructor and author of Mind Body Cleanse, explores how certain yoga poses can help stimulate digestion.
“There are many different poses that can help with your digestion,” he says. “Twists are quite remarkable because they not only massage, tone and rejuvenate your abdominal organs and promote digestion and peristalsis [the movement of food through the digestive tracts], but also improve the suppleness of the diaphragm.
“The spine also becomes more supple, allowing for correct spacing and alignment. This in turn improves blood-flow to the spinal nerves and increases energy levels.”
Here, Chris shares 3 yoga poses and stretches that could help your digestion:
Ardha Matsyendrasana -— Half Lord of the Fish.
Sit on the floor with your legs straight in front of you, buttocks supported on a folded blanket or block. Slide your left foot under your right leg to the outside of your right hip. Lay the outside of the left leg on the floor.
Exhale and twist toward the inside of the right thigh. Press the right hand against the floor just behind your right buttock, and set your left upper arm on the outside of your right thigh near the knee.
Pull your front torso and inner right thigh together. With every inhalation, lift a little more through the sternum, pushing the fingers against the floor to help. Twist a little more with every exhalation. Be sure to distribute the twist evenly throughout the entire length of the spine. Stay for 30 seconds to one minute, then release with an exhalation, return to the starting position, and repeat to the left.
Parivritta Trikonasana — Revolving Three Angle or Triangle Posture
From standing, turn your left foot in 45-60 degrees to the right and your right foot out to the right 90 degrees. Align the right heel with the left heel. Firm your thighs and turn your right thigh outward, so that the centre of the right kneecap is in line with the centre of the right ankle. Square your hip points as much as possible with the front edge of your mat. As you bring the left hip around to the right, resist the head of the left thigh bone back and firmly ground the left heel. Draw the left hand and arm as far forward as possible.
With an exhalation, turn your torso further to the right and extend forward over the front leg. Reach your left hand down, either to the floor (inside or outside the foot) or, if the floor’s too far away, onto a block positioned against your inner right foot. Beginners should keep their head in a neutral position, looking straight forward, or look at the floor.
More experienced students can turn the head and gaze up at the top thumb. From the centre of the back, between the shoulder blades, press the arms away from the torso. Bring most of your weight to bear on the back heel and the front hand. Stay in this pose anywhere from 30
seconds to one minute.
Exhale, release the twist, and bring your torso back to upright with an inhalation. Repeat for the same length of time with the legs
reversed, twisting to the left.
Sarvangasana — Shoulder Stand Pose.
Fold two or more firm blankets into rectangles measuring about 1ft by 2ft, and stack them one on top of the other. Or use blocks. You can place a sticky mat over the blankets or blocks to help the upper arms stay in place while in the pose.
Bend your elbows and draw them toward each other. Lay the backs of your upper arms on the blanket and spread your palms against the back of your torso. Raise your pelvis over the shoulders, so that the torso is relatively perpendicular to the floor. Walk your hands up your back toward the floor without letting the elbows slide too much wider than shoulder width. Inhale and lift your bent knees and straighten your legs toward the ceiling. Beginners, stay in the pose for about 30 seconds.
Gradually add five to 10 seconds to your stay every day or so until you can comfortably hold the pose for three minutes. Then continue for three minutes each day for a week or two, until you feel relatively comfortable in the pose. Again, gradually and five to 10 seconds onto your stay every day or so until you can comfortably hold the pose for five minutes. To come down, exhale, bend your knees into your torso again, and roll your back torso slowly and carefully onto the floor, keeping the back of your head on the floor.
If you have existing health problems or injuries, always seek professional advice before embarking on any new exercise regime.
Mind Body Cleanse by Chris James is published by Vermilion, priced £14.99.
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