How much is too much salt in my diet?
With respect to salt in our diet the message has always been clear – exceeding the World Health Organisation recommended daily allowance of 2g will raise your blood pressure, and increase your risk of heart disease and stroke. This has led some to consider cutting salt from their diets entirely, an approach which recent studies have suggested could do more harm than good.
First, we look at the damage that exceeding the 2g daily salt allowance can cause. A study from Mozaffarian et al. (2014) was particularly damning in this regard, looking at global sodium consumption collected data from surveys on sodium intake from 66 separate counties, calculating the cardiovascular effects of sodium intake according to age, sex and country.
The study found that the estimated mean level of global sodium consumption was 3.95g per day, nearly double the recommended daily allowance. From this, 1.65 million annual deaths from cardiovascular causes were attributed to sodium intake beyond World Health Organisation recommendations. 61.9% of these deaths occured in men, and 38.1% occurred in women.
Shortly following the study, the Institute of Medicine assembled an expert committee to evaluate the evidence for a relation between sodium and health outcomes. In the words of Suzanne Oparil (2015), “the committee concluded that most evidence supports a positive relation between high sodium intake and risk of cardiovascular disease” – in line with the research already discussed.
Should I adopt a low salt diet?
With findings like these in mind, you would be forgiven for concluding that salt in your diet is something to not only be wary of, but to consider avoiding altogether. More recent studies might dissuade you of this notion, however. Mente et al. (2018), concluded that sodium intake was associated with cardiovascular disease “only in communities where mean [salt] intake was greater than 5g/day” – two and half times greater than the recommended daily allowance.
In fact, when it comes to major reductions in salt, Mente et al. argue that “there is little evidence in terms of improved health outcomes”. Casting further doubt still, they suggest that there is no evidence “that free-living individuals [can] ever achieve such a low level” of salt as recommended by the World Health Organisation.
Alongside the Mozaffarian et al. (2014) study mentioned earlier, was another paper from O’Donnell et al. (2014). O’Donnell comments that “there is no convincing evidence that people with moderate-average sodium intake need to reduce their sodium intake, for prevention of heart disease and stroke”.
Our conclusion in response to the question of “should I adopt a low salt diet?”, therefore, should be “not necessarily”. As Mente et al. (2018) themselves conclude, “at moderate intake, sodium may have a beneficial role in cardiovascular health”. Further, it may play a “more harmful role when intake is very high or very low”. This is, in essence, true for many essential nutrients in the body.
The question we are left with is how much is too much, or indeed too little. The World Health Organisation’s recommendation of 2g/day is a good starting point, but as Mente et al. note, this guideline was based on “short-term trials of sodium intake and blood pressure”. They add that “while low sodium intake does reduce blood pressure...it may also have other effects, including adverse elevations of certain hormones associated with an increase in risk of death and cardiovascular disease”.
How can I reduce my salt intake?
If you are concerned that you may be exceeding your daily salt allowance on a regular basis, there are four quick changes you can make in your diet to temper your salt intake:
- Taste, then season. Sprinkling salt over a meal is automatic for a lot of people. It is a habit they carry out, almost without thinking. By tasting before seasoning, you see if the dish in front of you actually needs salt – which, more often than not, they don’t.
- Cut down on sauces. The majority of sauces – ketchup, mustard, brown sauce, soy sauce and gravy – are high in salt. Whenever reduced salt versions of the sauces you already buy are available, use them instead, or use your existing sauces sparingly.
- Season with spices. Flavour foods with black pepper, garlic, ginger, chilli, lemon and/or lime instead of salt. Remove the salt shaker from your kitchen counter and table top if you need to. As soon as you realise the seasoning options available to you outside of salt, you will wonder how you became so reliant upon it.
- Buy different brands. As soon as you revisit the labels of the brands you have been buying up to this point, you may be surprised to see how high their salt content is. Even foods that you wouldn’t think of as salty can be high in salt – for instance breakfast cereals, baked beans, sandwiches, packet or canned soups and instant noodles.