Low Salt, is it really healthy?
Just like we got cholesterol wrong, we may have been wrong about salt.
Examination of the basis for the original dietary salt restrictions, reveals flaws in the research. Recent research has identified that low salt levels increase risk much more than high salt levels. A new study of thousands of people around the world has identified that there is an optimum level of salt consumption (3-6 grams per day)
which is higher than current recommended levels. See below.
Many people do exceed the recommended daily levels. The concern linking excess salt to raised blood pressure may be over stated, with higher salt making a very small difference to blood pressure levels. Research I have seen, suggests that lower salt may assist about 30% of people by dropping blood pressure by a very small amount (1-4 mmHG), but for 20% of people blood pressure will rise similarly, while for the remainder, there will be no change at all.
If you have more dietary salt, this can have an impact on your overall fluid level, but the kidneys generally manage the overall sodium level and release excess salt in the urine. According the Dr. Paul Mason of Australia, the impact of excess dietary sodium is about 2mmHg in those people who are susceptible to this which is only about 20% of the population.
The Japanese diet is very high in salt and they have one of the longest life expectancies in the world. We need salt for many internal body processes including digestion, manufacture of bile, hormone production, it is critical for brain function and may be a mood booster. We now have to be aware of micro plastics in salt from evaporated sea water with 90% of salt produced this way showing some contamination, particularly high in Asia. A new salt substitute “Senomyx” is entering the food chain without any testing and can be called “artificial flavor” on food labels.
It is apparently common for some people switching over to a “fat” burner diet of low carbohydrates, to experience some leg cramping. This can apparently be caused by the reduction in sodium intake from the reduced consumption of salted processed foods, particularly cereals. Higher insulin levels signal the kidneys to limit the release of salt in urine, so that the effect of the keto diet’s reduced insulin level allows the kidneys to release further salt. Keto experts generally recommend increasing salt intake to overcome these problems. This effect is also enhanced by the tendency of carbohydrates to hold water, while a ketosis state is diuretic thus flushing more salt in the urine.
The causative string here is that higher sugars in the diet, including carbohydrates, cause an increase of insulin in the blood. The higher blood insulin level causes the kidneys to hold onto sodium which in turn causes the body to hold more fluid. This higher level of fluid is believed to elevate blood pressure. This conversely means that a higher carbohydrate (sugar) diet may actually have more effect of elevating blood pressure by increasing insulin levels than salt does.
The “Urinary sodium and potassium excretion, mortality and cardiovascular events” study by Martin O’Donnell et al. published in August 2014 in the New England journal of medicine, studied 102,000 people in 17 countries measuring their excretion of sodium and potassium first thing each morning and used this to establish daily consumption levels. The findings were that risk of death from all causes including cardiovascular events was sharply increased at sodium levels below 3 grams per day and also increased above 6 grams per day with the sweet spot at around 5g per day. Low salt was more risky than higher salt. This level is higher than current guidelines.
To follow the research check here: https://www.nejm.org/doi/full/10.1056/NEJMoa1311889
Studies have shown that for women, low salt can reduce bone health, increasing osteoporosis and the risk of hip fracture. Follow the research here: https://pubmed.ncbi.nlm.nih.gov/30228731/.
You can expect to supplement salt on a keto diet and most days, I add 1/2 tsp salt to one cup of green tea to keep levels up.
Salt is often supplemented with iodine which is essential for many body functions but particularly for brain development of babies during pregnancy. Studies show that some western children are being affected by very low iodine. If you are not eating iodized salt while pregnant, you should seek other sources of iodine for baby’s brain health.
In 2017 the Australian and New Zealand governments released a document titled,
“Nutrient Reference Values for Australia and New Zealand, BRIEF: Revised Sodium Nutrient Reference Values (2017)”, stating that the new upper limit (UL) was “not determined”.
Here is their summary in their words:
2017 UL (Upper Limit) REVISION FOR SODIUM FOR ADULTS – ‘NOT DETERMINED’
The UL is defined as the highest average intake likely to pose no risk in the general population. There is convincing evidence that as sodium intake increases, blood pressure increases. An analysis of data (currently available between 1200 and 3300 mg) failed to determine an identifiable point at which the relationship between higher sodium intakes and higher blood pressure did not occur. This means that increased sodium intake was associated with increased blood pressure at all measured levels of intake. Thus, the UL was revised from the 2006 UL of 2300 mg/day to ‘not determined’, reflecting the inability to identify a single point below which there is low risk. This should be interpreted as a need to reduce sodium intake in the general population, as there was no identifiably safe upper limit.
Unfortunately this summary fails to disclose whether, in their view, the increase in blood pressure for higher salt levels is significant or not. Their view could be that any increase is not welcome. A slight increase is expected, eg 2 mmHg, as mentioned by Dr. Paul Mason, however while this is an increase it may not be significant.
For further reading I suggest: “The salt fix” by Dr. James Dincolantonio.
George Elder, “Take Back Your Health”, Amazon $3.99. www.takebackyrhealth.com.