Sodium intake via the diet

Sodium is a mineral that occurs naturally in food or is added during processing in the form of sodium chloride (salt). Many vital bodily functions depend on an optimal sodium supply. Fluctuating levels can impair brain activity and disrupt heart rhythm. Older people in particular belong to the risk group...

Sodium, together with potassium, regulates the fluid balance in the body and keeps metabolic processes running. It must also be available in sufficient concentration for the transmission of muscle stimuli and the transmission of nerve impulses. According to the guideline of the German Nutrition Society (Deutsche Gesellschaft für Ernährung e. V.), the daily sodium requirement is at least 1500 mg. Due to the high salt content of western cuisine, this requirement can usually be adequately met.

Table salt (sodium chloride) contains 40 % sodium. It is mainly found in processed foods to which salt has been added. This is to improve the taste. The nutrition label on many food packages indicates how much of it is in the product. You can also recognise added sodium by the names monosodium glutamate, sodium nitrate, sodium saccharin, sodium benzoate or sodium bicarbonate. Some examples of foods high in sodium:

Buns and pretzels: Buns contain about 370 mg of sodium per 100 g. Salt crystals on the pretzel or pastry increase the sodium content. Pretzel sticks contain about 1800 mg of sodium per 100 g.

Sausages: The values range from about 700 mg (yellow sausage) to about 1,250 mg per 100 g (salami). Vienna sausages contain an average of 950 mg of sodium per 100 g. Ham also has a high sodium content because salt is needed for curing and seasoning.

Cheese: Gouda (45 % fat) contains about 500 mg, soft cheese about 800 mg, butter cheese (50 % fat) an average of 850 mg and feta even about 1,300 mg per 100 g.

Sea fish: Especially salted herring and smoked varieties (such as smoked salmon) contain a lot of sodium.

Ready-to-eat products: The high sodium content in canned soups comes primarily from salt, and some also contain sodium-rich additives such as monosodium glutamate. Packaged broths, which are often used as a base for soups and stews or for seasoning, as well as ketchup, ready-made sauces and marinades also contain a lot of salt. In pizza, ingredients such as dough, cheese, tomato sauce and sausage add up to a considerable amount of sodium. A 350 g pizza contains on average 4 - 5 grams of salt.

Milk and eggs naturally contain moderate concentrations of sodium (an L-weight egg contains about 80 mg). Vegetables and fruit also contain the mineral. The highest levels are found in chard, celery, artichokes, spinach, beetroot and carrots. Another source of sodium is mineral water, but the concentrations vary greatly between brands.

We rarely have to worry about an undersupply of sodium, as we consume it daily through our diet. In addition, one third of the sodium is stored in the bones and can be released into the blood by the body when needed. Nevertheless, certain circumstances can lead to a sodium deficiency. For example, diarrhoea and vomiting, when a lot of fluid and minerals are excreted within a short time. People who sweat a lot, for example at work, in the sauna or during sports, also lose sodium through their sweat.

If there is an insufficient supply of sodium, various deficiency symptoms occur. The first alarm signs are malaise, headaches, muscle pain, nausea or dizziness. A drop in blood pressure is also possible. However, these symptoms are rarely associated with a sodium deficiency. Especially a chronic undersupply (hyponatremia) can therefore remain undetected for a long time.

Too little water in the body, either through fluid loss or insufficient drinking, leads to an increase in the sodium concentration in the blood. The medical term is hypernatremia. Senior citizens in particular have an increased risk, as many have a less pronounced feeling of thirst. In the case of a short-term excess, our body increases sodium excretion via the kidneys. An overdose over a longer period of time, for example by consuming heavily salted food, can cause nausea, headaches, high blood pressure and cardiovascular diseases. The risk of osteoporosis and stroke also increases. In severe cases, the brain cells dry out, which can lead to states of confusion and clouding of consciousness.

Too little water in the body, either through fluid loss or insufficient drinking, leads to an increase in the sodium concentration in the blood. The medical term is hypernatremia. Senior citizens in particular have an increased risk, as many have a less pronounced feeling of thirst. In the case of a short-term excess, our body increases sodium excretion via the kidneys. An overdose over a longer period of time, for example by consuming heavily salted food, can cause nausea, headaches, high blood pressure and cardiovascular diseases. The risk of osteoporosis and stroke also increases. In severe cases, the brain cells dry out, which can lead to states of confusion and clouding of consciousness.

Too much but also too little sodium harms our body. Personal needs vary depending on age, physical exertion and state of health. A short-term oversupply of sodium hardly leads to problems in healthy people. However, hidden salt in food can be critical for kidney disease and high blood pressure patients. With a targeted food selection, it is possible to ensure a healthy sodium ratio in the body.