Magnesium content of food
is declining
The magnesium content in food crops and daily diet is becoming an important world-wide issue in food quality and human nutrition.31 Over the last 50 plus years there has been a marked decline in the magnesium (and other micronutrients) content of cereal seeds.32,33 Surveys have shown that two thirds of people in developed countries (including South Africa) receive less than their minimal daily magnesium requirement.4,32
Magnesium content of food is declining due to:
• Green revolution– a large increase in crop production in developing countries achieved using artificial fertilisers, pesticides and high-yield crop varieties32,33
• Yield dilution – fertilisers ensure a higher yield of fruits, vegetables and grains e.g. larger broccoli heads - but this increase is mostly due to a greater carbohydrate content of the foodstuff and not necessarily a proportionate increase in other micronutrients e.g. magnesium. As a result, there is a “dilution effect” of the micronutrients31-33
• Long-term unbalanced crop fertilisation with nitrogen, phosphorous and potassium over the last decades has led to high levels of competing elements and magnesium depletion32
• Acidic soils – about 70% of potentially arable land on earth is acidic. Acidic soils and low cation exchange capacity leads to lower magnesium levels32
• High rainfall in tropical regions – leaches magnesium from soil32
• Heat stress and droughty soil32
• Refining and processing of foods - may decrease magnesium content by about 85%.13,31
As magnesium is critical for the proper functioning of every organ in your body,3 it is vitally important that you ensure an adequate intake of magnesium, either through your diet or by consuming a magnesium supplement.
