Sodium and lithium: why a low-salt diet can push your level into the danger zone
Lithium (a mood stabilizer for bipolar disorder) and sodium are handled by the same part of the kidney, and they compete. Eat much LESS sodium than usual — a sudden low-salt diet, heavy sweating, or dehydration from illness — and the kidney holds on to lithium instead, so blood levels climb toward toxicity. Eat much MORE and lithium is flushed out faster, so it may stop working. The narrow safe range makes lithium unusually sensitive to this. Every number below is one ordinary serving, from USDA FoodData Central.
The part people get wrong
The rule for lithium is not low-salt or high-salt — it is STEADY salt. Pick a sodium habit and keep it consistent, and tell whoever manages your lithium before you start a diet, a cleanse, or a new exercise routine that makes you sweat. Be extra careful during vomiting, diarrhoea, or fever: fluid and sodium loss can raise lithium fast, and that is exactly when a level should be checked. NSAIDs (ibuprofen, naproxen) and some blood-pressure drugs also raise lithium levels — this is a drug to manage with a prescriber, not a web page.
Sodium in common foods — per serving, not per 100 g
Values from USDA FoodData Central for the serving shown. These are foods people actually eat: ranking the whole USDA database by density would put dried thyme and defatted soy flour at the top, which is accurate and no use to anyone.
| Food | Serving | Sodium (mg) |
|---|---|---|
| Table saltfor reference — 1 teaspoon | 1 tsp (6 g) | 2325 |
| Soy sauceregular | 1 tbsp (16 g) | 878 |
| Canned soupchicken noodle, condensed | 1 cup, prepared (245 g) | 866 |
| Hamsliced, regular | 3 oz (85 g) | 1010 |
| Pretzelshard, salted | 1 oz (28 g) | 385 |
| Cottage cheeselow fat, 2% | 1 cup (226 g) | 746 |
| Pickledill | 1 spear (35 g) | 283 |
| Breadwhite, commercial | 1 slice (28 g) | 147 |
| Cheddar cheese | 1 slice (1 oz) (28 g) | 180 |
| Potato chipssalted | 1 oz (28 g) | 149 |
| Eggwhole, cooked | 1 large (50 g) | 62 |
The medicines this affects
Drugs in our catalog from the classes involved — mood stabilizer. Each page carries that drug’s own FDA label.
Frequently asked questions
Which foods are highest in sodium?
Per serving, the highest on this list is table salt — 2325 mg in 1 tsp (6 g), per USDA FoodData Central. These are common foods rather than the absolute maximum in the USDA database: ranking every food by sodium density puts dried herbs and defatted soy flour at the top, which is true and useless to someone deciding what to have for dinner.
Do I need to avoid sodium if I take these medicines?
The rule for lithium is not low-salt or high-salt — it is STEADY salt. Pick a sodium habit and keep it consistent, and tell whoever manages your lithium before you start a diet, a cleanse, or a new exercise routine that makes you sweat. Be extra careful during vomiting, diarrhoea, or fever: fluid and sodium loss can raise lithium fast, and that is exactly when a level should be checked. NSAIDs (ibuprofen, naproxen) and some blood-pressure drugs also raise lithium levels — this is a drug to manage with a prescriber, not a web page.
Where do these numbers come from?
USDA FoodData Central (SR Legacy), for the household serving shown next to each food — not per 100 g. Per-100-g figures are what most "foods high in sodium" lists use, and they are misleading: nobody eats 100 g of dried thyme.
Sources
- Sodium in Diet — MedlinePlus (U.S. National Library of Medicine) ↗
- Lithium Carbonate — FDA label, Dosage & Administration / Drug Interactions (DailyMed) ↗
- USDA FoodData Central, SR Legacy ↗
Nutrient values are USDA reference data for the serving shown and vary with variety, growing conditions and cooking. This page is general information, not medical advice — never change your diet or your dose on the strength of a web page. Talk to whoever manages your treatment.