Potassium is an essential mineral that some people tend to lack. It is essential for the transmission of nerve impulses, as well as muscle contraction (particularly the heart) and good kidney function, and plays a role in fighting high blood pressure, a major risk factor for cardiovascular disease and stroke. World Stroke Day is October 29.

Potassium is naturally present in pulses, such as white beans, chickpeas and lentils, vegetables (chard, spinach, potatoes, cabbage, mushrooms), fruit (avocado, banana, apricots, citrus fruit, blackcurrants), and dried fruit and nuts (walnuts, almonds, pistachios, dates, figs).

It is also found in meat and fish, especially oily fish (salmon, sardines and mackerel), as well as chocolate and wholegrain cereals.

Only fats such as butter, crème fraiche, oil and margarine don't contain this mineral.

The top 10 most potassium-rich foods include lentils (810mg per 100g), dried dates (790mg), prunes (732mg), almonds (705mg), spinach (662mg), avocado (650mg), chestnuts (600mg), mushrooms (520mg), walnuts (450mg) and apricots (440mg).

Potassium, which helps prevent muscle cramps, is particularly beneficial for athletes to help counterbalance the production of lactic acid when muscles work hard. Chia seeds, for example, contain more potassium (407g/100g) than bananas (360g/100g) and can be particularly beneficial for the recovery phase.

Recent studies show that low dietary potassium can lead to calcified arteries and aortic stiffness.