The mineral sodium is present in the bones and body fluids. Its role in the body is to balance levels of pH, fluid and electrolytes, and in used in the formation of digestive juices, iron and eliminating carbon dioxide. Sodium is also needed for muscle contraction and drawing in nutrients from cell walls. It is the main component of blood plasma and keeps blood from clotting.

Sodium deficiency can be caused by excessive heat and exercise, where it is lost through the body from sweat. This can lead to dehydration, nausea, heat exhaustion, low blood pressure and poor appetite. A long-term sodium deficiency can also cause kidney stones and muscle cramps.

Most diets contain enough sodium whilst noting that sodium chloride (table salt) is not an organic source of sodium. Natural sources of sodium include:

• Strawberries
• Sunflower and sesame seeds
• Carrots
• Celery
• Broccoli
• Raisins