Bárbara Pinho in Chemistry World:
When we think about the food we ate when we were younger, we might be inclined to say that it was tastier and healthier than what we eat today. And while we may be saying this out of a nostalgic tendency, researchers have been looking for a more scientific answer. In several papers, researchers have used food tables – country-by-country compendia of historical information on the mineral composition of foods – to report an apparent decline in micronutrients such as iron, vitamins and zinc in fruit and vegetables over time.
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