By Michael Bamuwamye
Salt is a crystalline mineral composed primarily of the chemical compound, sodium chloride. In small quantities, salt is necessary for human health, but in excess, it is harmful.
Salt is the main source of sodium, which is vital for controlling the amount of water in the body, maintaining the normal pH of blood, transmitting nerve signals and helping muscular contraction. Protein foods generally contain more naturally existing sodium than vegetables and grains, whereas fruits contain little or none.
This means to avoid the effects of excessive salt, especially in adults, vegetables and fruits should form a larger portion of diet.
Increased consumption of processed foods has led to a corresponding increase in salt consumption and consequently, to health risks associated with such high intake.
Health effects of excessive salt intake can be categorised into acute and chronic effects. Acute effects include muscle cramps, dizziness, or electrolyte disturbance, which have been shown to cause neurological problems, or death.
On the other hand, long-term effects include those associated with stroke and cardiovascular diseases, high blood pressure, and left ventricular hypertrophy (enlargement of the heart — a strong risk factor for cardiovascular disease).
Excessive salt, or sodium intake, combined with inadequate water-intake can exacerbate kidney disease, while decreased salt intake is suggested to treat oedema (fluid retention).
There is also evidence that severity of asthma may be made worse by high salt intake although the latter is not a direct cause of asthma.
Besides, eating highly salted foods results in increased thirst, and relieving such thirst with high-sugar or high-calorie beverages like soft-drinks and beer may contribute to weight gain and subsequently obesity. Hence reduced salt intake may be a means of overcoming obesity.
Current recommendations indicate that in order to prevent chronic diseases, the average consumption of salt should be less than 5g/day (World Health Organisation 2003, WHO 2006). However, while there is no data available for Uganda, salt intake across the world varies between 5g and 18g per person per day. This level of intake increases the risk of health problems and, therefore, some health authorities have recommended limitations of dietary salt intake.
Stomach cancer is also strongly associated with high levels of salt intake. Cancer of the stomach is the fourth most common type of cancer worldwide. While stomach cancer is decreasing rapidly in high-income countries, it remains common in the developing countries.
This calls for high level of vigilance on the type of foods and environments we expose ourselves to. One of the exposures associated with stomach cancer is salt and salt-preserved foods. Other foods include chilli, processed meat, smoked foods, and grilled (broiled) and barbecued animal foods.
Vegetables like garlic and onions, as well as fruits are known to protect against stomach cancers. Legumes including soya and soya products also protect against stomach cancer.
The overall advice, therefore, is to tremendously reduce our salt intake and include more fruits and vegetables in our diet in order to reduce our risk to strokes and cancers in general.
The writer is a food scientist, specialising in food toxicology and nutritional biochemistry