A recent study from UK-based Deep Science Ventures (DSV) says many crops—including wheat, apples and carrots—may provide about half the nutrients they did 60 years ago.

Among the nutrients reported to be declining are potassium, iron, selenium and zinc.

DSV senior associate Will Summers cites climate change, soil degradation and crop breeding for faster growth and higher yields at the expense of nutrition as possible causes.

Summers and others warn that declining nutrient levels could contribute to micronutrient deficiencies, including in the U.S. and U.K., where diets can be high in calories but low in nutrients.

Summers discussed the problem and potential solutions in an interview with Here & Now’s Robin Young.