The world is in love with salt, the tiny white particles of seasoning that somehow makes food taste so much better.
But we might have taken the love affair a bit too far. In 2010, it was estimated that up to 4 million people died from eating too much salt. We’ve become so dependent on salt that our bodies were genetically designed to eat ten times less salt than we do today.
Salty and Saltier
Salt is a naturally occurring mineral made from sodium and chloride. Sodium is an essential nutrient in the body. It regulates the water balance inside and outside of cells while our muscles and nerves require sodium to function properly.
So while we do need sodium, the lack of it is not an issue. There is rarely a case in the medical field where someone presents with having insufficient dietary sodium. The body requires less than a 1/4 teaspoon of sodium and our kidneys are designed to conserve sodium in the body, preventing it from being lost in the urine. Pair this with the fact that our natural food sources contain enough sodium to sustain the body – even in plant foods which has trace amounts of sodium.
The problem that we’re facing now is that we’re literally becoming too salty which unfortunately has severe health consequences. The typical Western diet is notoriously high in salt with 90% of Americans aged 2 and older (so including children!) eating over the recommended daily intake.
The Infamous Gabelle
Our love for salt began when we discovered that it could be used to preserve food. Salt became a highly coveted ingredient with high economic value and salt taxes, such as the gabelle in France, were introduced. When the freezer and refrigerator were invented, salt was no longer needed for that purpose. However, humans were already accustomed to using salt as seasoning, in making cheese and adding to their livestock feeds which saw the daily usage of salt increase significantly over time. This was also the time when processed foods were beginning to revolutionise the food industry.
Under a Teaspoon of Salt
The figures will vary across national guidelines but the World Health Organisation recommends consuming less than 5 grams of salt per day which is just under a teaspoon. However in most countries, we consume an average of 9 to 12 grams of salt per day which is more than twice the recommended amount.
Salty Blood and Pickled Arteries
Eating too much salt can cause a host of health problems including kidney disease, osteoporosis and stomach cancer. It can also result in water retention where our bodies try to compensate for this excess fluid and salt by increasing our blood pressure. Over time, a condition called hypertension can develop which is characterised by consistently high blood pressure.
High blood pressure puts strain on blood vessels all over the body. They become damaged and weak preventing blood flow to end organs such as the brain and eyes. Other organs such as the heart and kidneys are forced to work harder against the higher pressure. Consequences of high blood pressure include: strokes, heart attacks, aneurysms, blindness, sexual dysfunction and dementia.
Salt Raises Blood Pressure
It’s been well documented in the scientific literature that sodium can raise blood pressure. Studies have shown how a single meal, such as a bowl of soup, containing the typical amount of salt in the Western diet can stiffen arteries and increase participants’ blood pressure in just three hours (compared to a different group who had the same soup with no added salt).
Another study recruited people with high blood pressure placed them on a sodium-restricted diet and their blood pressure dropped. When researchers gave the patients a sodium pill of varying concentrations, their blood pressure proportionately increased back up again.
In another blog post, we talked about how eating foods high in nitrates and anti-oxidants may help with high blood pressure. It’s been shown that high salt intake suppresses an anti-oxidant enzyme called superoxide dismutase which usually counteracts free radicals. Without it, free radicals can build up in the arteries and impair arterial function.
The Normalcy of High Blood Pressure
In medical school, we learnt that children start off with a lower blood pressure and as they age, their blood pressure starts to increase to ‘normal’ levels. The optimal blood pressure for many of us is anything less than 120/80. Anything higher than 140/90 is considered high blood pressure.
But what if the norm wasn’t exactly ‘normal’? We know that age-related increases in blood pressure is a thing in the Western society… but is that because we’ve evolved with eating a diet high in salt? What if salt wasn’t a big part of our diets? Could our ‘normal’ blood pressure actually be lower?
When scientists measured the blood pressure of the Yanomami Indians, who are strangers to salt and processed foods, they found an average blood pressure of 95/61 in everyone – from the youngest to the oldest. The pattern of age-related blood pressure changes was very different to that of the Western population.
Where is the Salt Coming From?
Three quarters of our salt intake comes from processed foods. The remaining quarter comes from added salt during cooking or at the table. So while we can reduce our salt intake at home, a whole-foods diet is the best way to get the full effect.
Also make it a plant-based diet at that. Meat is significantly high in sodium compared to plant foods. Processed meats such as bacon and ham are salted during their preparation process (you can taste how salty it is compared to a normal steak). But even if the meat hasn’t been processed, salt is often added to meat (e.g. plumped chickens) to increase their water, total weight and thus, profits.
Unfortunately, salt is so deeply ingrained in our cooking culture that no one blinks twice as a heaped teaspoon (more than the recommended daily amount) of salt is poured into the pan for dinner. Salt shakers are on tables everywhere and interestingly, 1 out of 3 people add salt to their foods before tasting it! We’re all so accustomed with this high standard of salt in our foods that obviously no one (including ourselves!) wants to serve up ‘bland’ food. Restaurants add lots of salt into their dishes to make it enjoyable for everyone and the highly salted processed foods make natural, whole foods taste like cardboard. (Try making your own potato chips at home and see how much salt you need to pour in to achieve the same taste as your local takeaway shop).
Thankfully, we can re-train our tastebuds to appreciate less salty foods. A longitudinal study placed a group of people on a low-salt diet and measured their salt preferences over time. Initially they craved their usual, high-salt soups but eventually they started to enjoy and even prefer low-salt and unsalted soups. When the group were asked to make their own soups, they actually added in less salt than they predicted.
Un-Pickle Your Body
If the world reduced its salt consumption by 9.5%, over 500,000 strokes and 480,000 heart attacks could be prevented and it could save over $30 billion in medical costs. Unfortunately, since the salt mill is influenced by lots of politics, policies and big corporations, it takes a lot of effort to reduce even 5% of the world’s salt intake.
However, that shouldn’t deter us from doing our best to reduce our salt intake. There are lots of personal health benefits in doing so and we can encourage our friends and family to do it together with us.
We’ve written a more in-depth article about how to reduce your salt intake here!
Lowering Blood Pressure with a Plant-Based Diet
If you want to know more about blood pressure or other ways to reduce it then you’re going to love these articles!
- How Eating High Nitrate Foods and Anti-oxidants can Reduce Your Blood Pressure
- Did You Know Flaxseeds are Potent Anti-hypertensives?
- 5 ways to eat less salt
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