What is sodium deficiency and how much sodium do you need every day?
Sodium deficiency, also known as hyponatraemia, is when your body does not have an adequate supply of the vital mineral sodium. Sodium is an electrolyte that plays a central role in regulating fluid balance, nerve and muscle cell conduction and blood pressure. It is also involved in many metabolic processes.
The recommended daily intake of sodium for adults is 1,500 milligrams (1.5 grams). This corresponds to around 3-4 grams of table salt (sodium chloride). With heavy sweating, e.g. due to sport or heat, the requirement can increase to up to 6 grams of salt per day. Certain illnesses such as diarrhoea or vomiting also cause you to lose more sodium, which then needs to be supplemented.
Sodium deficiency symptoms
The symptoms of a sodium deficiency can be very varied and depend on the severity of the deficiency. Possible signs include:
- Nausea and vomiting
- Headaches
- Confusion and lethargy
- Muscle cramps and weakness
- Dizziness and fainting
Sodium deficiency causes
The most common cause of a sodium deficiency is excessive loss due to heavy sweating, diarrhoea or vomiting. Particularly at risk are:
- athletes who sweat a lot
- People with febrile infections or gastrointestinal illnesses
- Seniors, as the feeling of thirst often decreases in old age
- People with certain kidney diseases such as syndrome of inadequate ADH secretion (SIADH)
- People with heart failure or liver cirrhosis, as oedema often occurs here
Certain medications can also promote a sodium deficiency by increasing sodium excretion via the kidneys. These include, for example, diuretics ("dehydration tablets"), some antidepressants or ACE inhibitors for the treatment of high blood pressure.
Inadequate dietary sodium intake is rarely the sole cause of a deficiency, but it can exacerbate it. Healthy people generally achieve the recommended intake of 1.5 grams of sodium (3-4 g of salt) per day with a balanced diet.
Sodium in food
There are many good sources of sodium, both plant and animal-based. Here is an overview of the 10 most sodium-rich foods (plant or animal) with their average sodium content per 100 g:
Vegan sources of sodium
Vegan sodium sources: Sodium content per 100 g
1. Table salt: 38.8 g
2. Soy sauce: 5.5 g
3. Capers: 2.4 g
4. Green olives: 1.6 g
5. Sour cucumbers: 1.2 g
6. Wakame (raw): 0.9 g
7. Sauerkraut: 0.7 g
8. Kimchi: 0.5 g
9. Peanut butter: 0.5 g
10. Tomatoes (cooked): 0.5 g
Animal sources of sodium
Animal sodium sources: Sodium content per 100 g
1. Anchovies (in oil): 3.7 g
2. Salami (pork): 2.3 g
3. Blue cheese: 1.8 g
4. Parmesan: 1.8 g
5. Bacon (cooked): 1.7 g
6. Cream cheese: 1.6 g
7. Pecorino: 1.4 g
8. Swiss cheese: 1.4 g
9. Mussels (cooked): 1.2 g
10. Feta: 1.1 g
The majority (approx. 75%) of your daily sodium intake comes from processed foods and added table salt. Only around 10-12% is naturally contained in food.
To avoid an oversupply, you should only enjoy processed products and high-salt foods in moderation. Use herbs and spices instead of salt to flavour your dishes. Also pay attention to the salt content of ready-made products and out-of-home meals.
Frequently asked questions
How does a sodium deficiency manifest itself?
Sodium deficiency can be characterised by symptoms such as tiredness, weakness, nausea, vomiting, headaches and muscle cramps. In severe cases, confusion, disorientation and even seizures can also occur.
What can be done about sodium deficiency?
To treat a sodium deficiency, it is important to increase sodium intake, either through sodium-rich foods or, in severe cases, through infusions. It may also be necessary to treat underlying illnesses and adjust medication.
How can I consume more sodium?
In order to take in more sodium, you should include more sodium-rich foods such as olives, savoury biscuits, crisps, bread, cheese and marinated fish products in your diet. Special drinkable meals with a balanced nutrient composition can also help to cover your sodium requirements.
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Sources
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