Salt

Sodium is essential for maintaining blood volume, and its restriction is almost always unphysiological and irrational because reduced blood volume diminishes oxygen and nutrient delivery to all tissues. 2 Peat argued that the common craving for salt reflects a real biological problem, often driven by increased adrenalin, and that satisfying this craving can prevent water retention and edema. 2 He noted that in pregnancy, low blood volume from salt restriction fails to nourish the fetus, causing the kidneys to release renin, which increases blood pressure; supplementing salt was shown to lower blood pressure and prevent toxemia. 7

The body’s ability to retain sodium is critically dependent on thyroid function and carbon dioxide production. 2 Hypothyroidism causes a constant loss of sodium through the kidneys, and as sodium is lost, the adrenals increase aldosterone to compensate. 3 While aldosterone retains sodium, it does so at the expense of magnesium, instructing the kidneys to waste it. 2 Therefore, a low sodium intake relative to hormonal needs activates the renin-angiotensin-aldosterone system (RAAS), a factor recognized in hypertension, kidney disease, and heart fibrosis, while also increasing serotonin and sympathetic nervous system activity. 2 Peat explained that simply increasing sodium intake compensates for low thyroid function by turning off aldosterone, which directly lowers inflammation and stops magnesium loss. 8

Peat emphasized that salt, along with protein, progesterone, and thyroid, is a primary factor for maintaining brain temperature and function. 1 He described salt as anxiolytic and anti-inflammatory, noting that it stabilizes blood sugar, lowers adrenaline, and prevents the hyperventilation that causes carbon dioxide loss and a shift to lactic acid metabolism. 2 He cited a population in Mongolia consuming an average of 30 grams of salt per day with no hypertension, and observed that the body adjusts completely to massive changes in salt consumption within two or three days if the person is otherwise well-nourished. 2 Roddy confirmed that salt was a major therapeutic aid for him, though he noted that excessive intake beyond natural taste could cause intestinal injury and diarrhea. 4

Regarding salt quality, Peat recommended canning and pickling salt as a very pure form of sodium chloride, free from the added iron and free-flowing agents found in standard table salt. 10 He dismissed the mineral content of colored salts like pink Himalayan or sea salt, stating that while they may contain dozens of minerals, most of those are toxic, and the iron oxide responsible for the pink color is undesirable. 10 He also warned against "natural" curing agents like celery juice powder used in bacon, explaining that they contain exactly as much nitrate and nitrite as pure chemical cures, but with the addition of extreme allergens and inherent toxicity from the plant material. 2