One of the most gratifying rewards of having written The Paleo Diet in 2002 and having been involved in the Paleo movement from its very beginnings is that I receive numerous queries about various nutritional aspects of this lifelong way of eating. Clearly, I nor anyone else, have an inside track to all dietary questions that may arise about contemporary Paleo diets. However, I am happy to share with you the information I have compiled over more than 25 years of my research into this fascinating topic.
As the Paleo Diet gains traction and notoriety worldwide, it seems that part of the original idea has become partially diluted as more and more people discover and write about this lifetime nutritional program. I am flattered by the huge number of Paleo books and cookbooks released to market and available for purchase on Amazon, Barnes & Noble, and other outlets. These books and authors are a testament to the worldwide success and effectiveness of The Paleo Diet.
Unfortunaely, as I browse Paleo cookbooks and magazine recipes, I see that many authors have decided to add sea salt to their recipes, presumably in lieu of regular salt. Before I get into the scientific details let me make it clear from the beginning that neither sea salt nor conventional manufactured salt should be considered “Paleo,” as both were rarely or never consumed by our hunter gatherer ancestors, and both maintain nutritional qualities that adversely affect our health when consumed regularly.1
Sea salt contains high concentrations of sodium chloride (NaCl), just like manufactured salt. Sea salt is nothing more than evaporated sea water and can be mined from naturally occurring beds of rock salt or manufactured by solar evaporation of sea water. The salinity (concentration of all dissolved salts) in sea water is usually 35 parts per thousand (35 0/00), but varies somewhat in various oceans.
The salinity of sea water near the mouth of a large fresh water river, like The Amazon, is lower, but the percentages of all salts in all sea water remains constant.2, 3
You can see from the Table 1 and Figure 2 that sea salt contains high concentrations of salt (NaCl) amounting to 85.62% of all the dissolved salts. Now let’s contrast sea salt to commercially manufactured table salt. Table Salt is refined sea salt, rock salt or lake salt in which almost all impurities are removed leaving pure NaCl. Most table salt is produced using vacuum pan refining and is typically 99.8 to 99.95 pure NaCl.4 Under US law, 2% of salt by weight can include the following additives:
1. Anti-caking agents (typically calcium silicate) are added to table salt.
2. Frequently iodine (a mineral that prevents goiter) is added to table salt in the form of potassium iodide (0.006% to 0.01%).
3. Along with stabilizers (sodium bicarbonate, sodium thiosulfate or dextrose) to prevent degradation of the iodine.
There is absolutely no doubt that the average American consumes excessive amounts of salt which in turn may adversely affect health and well being.1
From Table 2 and Figure 3, you can see that far and away, processed foods are the highest contributor (77%) of salt to the American diet. Because processed foods generally are not part of the contemporary Paleo Diet, you will not have to worry about salt – that is unless you add sea salt to your Paleo menu and Paleo recipes. And if you do so, you can see that the salt (NaCl) concentration of sea salt (85.62%) is not much better than manufactured salt (99.8%).
In Table 3, I have presented the top 10 food sources of salt in the U.S. Diet.5 Note that almost all of these high salt foods are not part of The Paleo Diet. If you decide to prepare your Paleo meals or recipes with sea salt, you will be changing a once healthful, low-salt Paleo diet with to high salt diet. The choice is yours, but know that sea salt is not healthier than conventional salt and in fact, may be worse.
On paper, it appears that sea salt is more nutrient dense than table salt and may be nutritionally superior? Unfortunately both salts have undesirably high concentrations of salt (NaCl) as I have pointed out. Animal studies show sea salt to increase hypertension (high blood pressure) compared to table salt.6, 7
Many people including physicians and nutritionists assume that salt’s (NaCl) detrimental health effects occur only from the sodium ion (Na) contained within salt. Yet human experimental studies show the chloride anion is also responsible.8, 9 Chloride (Cl) yields a net acid load to kidney producing a slight metabolic acidosis that promotes high blood pressure, osteoporosis and kidney stones. These diseases along with stomach cancer and stroke are also associated with high salt consumption. Other less well recognized chronic illnesses known to be caused by a high salt diet include: Menierre’s Syndrome (Ear ringing), insomnia, motion sickness, asthma and exercise induced asthma.
Finally, an obscure fact in medical literature is dietary salt loading in even healthy subjects has been shown via MRI to:
- Increase intracellular Sodium (Na)
- Reduce intracellular Potassium (K)
- Increase intracellular Calcium (Ca)
- Decrease intracellular Magnesium (Mg) and reduce intracellular ph (increases acidity)10
All of these intracellular ionic changes are known to be associated with or promoters of a variety of cancers.11-13
Salt is definitely not Paleo, and neither is sea salt.
Loren Cordain, Ph.D., Professor Emeritus
1. Cordain L, Eaton SB, Sebastian A, Mann N, Lindeberg S, Watkins BA, O’Keefe JH, Brand-Miller J. Origins and evolution of the Western diet: health implications for the 21st century. Am J Clin Nutr. 2005 Feb;81(2):341-54
2. Castro P, Huber M. Marine Biology, McGraw-Hill, 9th Ed., New York, NY, 2012.
3. Baseggio G. 1974. The composition of seawater and its concentrates. Proc. 4th Int. Symp. Salt Vol. 2, pp. 351-358. Northern Ohio Geological Society, Inc., Cleveland, OH.
4. Kurlansky M. Salt, A World History. Penguin Books, NY, NY, 2002.
5. Centers for Disease Control and Prevention (CDC). Vital signs: food categories contributing the most to sodium consumption – United States, 2007 – 2008, February 7, 2012.
6. Dahl LK, Heine M. The enhanced hypertensogenic effect of sea salt over sodium chloride. Am J Cardiol. 1961 Nov;8:726-31
7. Dahl LK, Heine M. Effects of chronic excess salt feeding. Enhanced hypertensogenic effect of sea salt over sodium chloride. J Exp Med. 1961;113:1067-76
8. Kurtz I et al. Effect of diet on plasma acid-base composition in normal humans. Kidney Int 1983;24:670-80
9. Boegehold MA, Kotchen TA. Importance of dietary chloride for salt sensitivity of blood pressure. Hypertension. 1991 Jan;17(1 Suppl):I158-61.
10. Resnick et al. Intracellular ionic consequences of dietary salt loading in essential hypertension. J Clin Invest 1994;94:1269-76
11. Jansson B. Geographic cancer risk and intracellular potassium/sodium ratios. Cancer Detection and Prevention 1986; 9:171-94
12. Lee AH, Tannock IF. Heterogeneity of intracellular pH and of mechanisms that regulate intracellular pH in populations of cultured cells. Cancer Res. 1998 May 1;58(9):1901-8.
13. Mijatovic T et al. Cardiotonic steroids on the road to anti-cancer therapy. Biochim Biophys Acta. 2007 Sep;1776(1):32-57.