The toxicity of salt.

Area of Science:

• Nutritional Science
• Cardiovascular Health
• Toxicology

Background:

• The role of sodium toxicity in chronic diseases, particularly essential hypertension, remains a subject of debate.
• Documenting the insidious effects of moderate chronic sodium consumption is challenging due to environmental influences and genetic predispositions.

Purpose of the Study:

• To investigate the etiological role of chronic excess sodium ingestion in essential hypertension and its sequelae.
• To explore the correlation between dietary salt, stroke, gastric cancer, and the protective role of dietary potassium.

Main Methods:

• Review of epidemiological, clinical, and animal studies on chronic sodium excess and hypertension.
• Analysis of correlations between dietary salt intake and the incidence of stroke and gastric cancer.
• Examination of the potential protective mechanisms of dietary potassium against sodium toxicity.

Main Results:

• Chronic excess sodium ingestion is an important etiological factor in essential hypertension and its sequelae, particularly in genetically susceptible individuals.
• Positive correlations were observed between dietary salt and the incidence of stroke and gastric cancer.
• Dietary potassium may offer some protection against the toxic effects of sodium through an unknown mechanism.

Conclusions:

• Optimal daily salt intake for humans is estimated at approximately 3.5 g/day or less, contrasting with current consumption in developed countries (8-40 g/day).
• Modern food processing often reduces protective potassium levels, exacerbating the risks associated with high sodium intake.
• Recognizing sodium's toxicity and understanding its mechanisms can significantly advance preventive medicine, potentially by identifying susceptible individuals and implementing dietary interventions to prevent or minimize hypertension.