Humans and salt

When life was first stirring on the earth, salt was already playing its part. Salt and other basic chemical substances combined with water in the primordial oceans to form a “primeval broth” in which the first micro-organisms were able to develop.

Multi-cellular man has also retained something of the primordial ocean within himself since the start of his three million years of development, in the form of what is known as the extracellular fluid that surrounds our cells. One litre of this fluid contains 9 grammes of common salt.

Salt is a special substance with a unique taste and a diverse range of effects. Fine food can only take a few pinches of salt, but it can be added generously to the water for an invigorating bath, while the pain of “rubbing salt in a wound” is not only proverbial but a literal fact.

Blood (in our arteries), sweat (on our brows) and tears (of joy on our cheeks) make it clear that salt is the food of life. Water, heat and salt buoy our heavy bodies up in a brine bath to relax our minds, care for our skin and activate our circulation.

A natural medicine

Medical science accorded a position of universal importance to salt in days gone by. Salt was also a medicine. It played its part in hygiene and was regarded as an effective diet. Even in those days, the therapeutic effects of sea water and brine baths were appreciated.

One example is the 0.9% common salt solution that is essential in case of accidents involving blood loss or as a carrier fluid for other drug solutions in infusions. This physiological and isotonic solution of common salt helps to save lives.

However, salt is also put to successful use in naturopathy and for home remedies. Saltwater solutions in specified concentrations can reduce swelling in inflamed mucous membranes, and they are helpful with colds or inflammations of the throat and pharynx. Knowledge about the therapeutic effects of brine springs has also been handed down to modern times. Brine baths are used for a whole series of complaints, in particular those affecting the musculoskeletal system (gout, rheumatism and sciatica). Warm brine baths are also popular as a form of post-operative treatment after orthopaedic or neurological interventions, for injuries due to accidents, consequences of paralysis, cardiovascular disorders and diseases of the respiratory tract. Many renowned spas came into being during the Roman era.

Skin diseases are treated successfully with salt, light and heat, either directly on the seashore or in clinics. People suffering from psoriasis find relief in the spas of the Dead Sea. Over 200 years ago, the particularly bracing climate of the North Sea was already known for its beneficial influence on respiratory tract diseases.

The roles of sodium (Na) and chlorine (Cl)

Sodium also plays a key part in transmitting stimuli along the pathways of our nervous system. When at rest, nerve cells contain potassium ions and their cell membranes are impermeable to sodium ions. But when the cell is stimulated, the membrane suddenly becomes permeable and sodium ions flow in, causing a change in the cell’s electrical condition. The nerve fibres pass this on as an electrical signal. If the body’s potassium-sodium ratio is disrupted due to a lack of salt, symptoms such as fatigue, enervation, sluggish reactions and muscular cramps may occur. However, sodium cannot be replaced by potassium. Dietary recommendations are often misunderstood in this regard.

Sodium ions perform their main task in the nervous system, whereas chloride ions are crucially important for the digestive function. In addition to mucus and enzymes, the gastric juices also contain hydrochloric acid which makes them strongly acidic (pH value: 1.0–1.5). This acidity is important because it kills pathogens contained in food and prepares food protein for further digestion.

The taste of tears and sweat makes us aware that we have salt in our bodies. For a body weight of 70 kilograms, the salt content is in fact 125 grams (see the NaCl distribution chart). However, this is not a constant value because we excrete salt every day through sweat and urine. Humans and animals feel compelled to replace lost salt. Going without salt for lengthy periods results in deficiency symptoms, illnesses and even death in extreme cases. However, there is a risk of salt deficiency with unbalanced diets, thirst sensation disorders in elderly people, extreme diarrhoea and endurance sports.

How much salt does a person need?

Salt requirements are highly individual and they vary according to weight, physical activity and state of health. Adults need 4 to 6 grammes of common salt per day. With balanced nutrition, these quantities are contained in meals. In Germany, Austria and Switzerland, statistics indicate that this guidance figure is exceeded by one to two grammes per day.

Iodine in salt – fighting off gout

Salz trägt als ideales Trägermedium für Spurenelemente zur Gesundheit bei. Der menschliche Körper braucht zur Regelung der Schilddrüsenfunktion Jod. Der Tagesbedarf liegt bei einem Erwachsenen zwischen 100 bis 150 Mikrogramm (0,00015 g). Eine verschwindend kleine Menge – und doch ist die Aufnahme durch Nahrung oder Getränke nicht garantiert. Ein Mangel an Jod führt zu Kropf und anderen Mangelerscheinungen.

Schon Anfang des Jahrhunderts wusste man über die Folgen des Jodmangels Bescheid. Lokalen Versuchen folgte 1922 die erste flächendeckende Salz-Jodierung. Die Schweiz übernahm damit eine Pionierrolle. Seit damals fügen die Schweizer Salinen im Auftrag der Behörden dem Speisesalz Kaliumiodid bei. Sicher kann der Rückgang des Kropfes und der Jodmangelkrankheiten im Wesentlichen darauf zurückgeführt werden. Die Speisesalz-Jodierung ist heute ein wichtiges Element im weltweiten Gesundheitsprogramm der WHO und der UNICEF.

Fluorid im Salz – den Zähnen zuliebe

Das Schweizer Speisesalz JuraSel® gibt es nicht nur mit Jod, sondern auch mit Fluor. Die Zahnmedizin hat schon früh festgestellt, dass die regelmässige Umspülung des Zahnschmelzes mit Fluorid bereits in kleinsten Konzentrationen konservierend und härtend auf den Zahnschmelz wirkt. Nicht nur in der Wachstumsphase, selbst bei betagten Menschen wirkt Fluor. Fluorid im Speisesalz ist deshalb eine sinnvolle und erst noch billige Kariesprophylaxe für die ganze Bevölkerung.