We answer your common questions about nutrients in food.
Q: "I've heard today's food has way less nutrients than, say, 100 years ago. Is that true?"
Although data is fairly limited, it does seem the nutrient quality of our food has declined, but the level of decline appears to be very small.
A study of the mineral content in various produce, which compared current data to that from the 1930s, found concentrations of several minerals had declined in both the US and the UK. A difficulty with this research is analytical techniques have changed and improved since the 1930s.
Other researchers have compared produce grown from modern day cultivars with seeds used in the past. One study measured the protein content of maize, a crop where modern hybrids have led to hugely increased yields over the past 80 years. They found the amount of protein in maize had fallen from 13.3 per cent to 12.2 per cent. Similar results were found in a study of soy bean protein over the past 60 years.