Were the people who foraged for these wild foods healthier than we are today? They did not live nearly as long as we do, but growing evidence suggests that they were much less likely to die from degenerative diseases, even the minority who lived 70 years and more. The primary cause of death for most adults, according to anthropologists, was injury and infections.

Each fruit and vegetable in our stores has a unique history of nutrient loss, I’ve discovered, but there are two common themes. Throughout the ages, our farming ancestors have chosen the least bitter plants to grow in their gardens. It is now known that many of the most beneficial phytonutrients have a bitter, sour or astringent taste. Second, early farmers favored plants that were relatively low in fiber and high in sugar, starch and oil. These energy-dense plants were pleasurable to eat and provided the calories needed to fuel a strenuous lifestyle. The more palatable our fruits and vegetables became, however, the less advantageous they were for our health.

The sweet corn that we serve at summer dinners illustrates both of these trends. The wild ancestor of our present-day corn is a grassy plant called teosinte. It is hard to see the family resemblance. Teosinte is a bushy plant with short spikes of grain instead of ears, and each spike has only 5 to 12 kernels. The kernels are encased in shells so dense you’d need a hammer to crack them open. Once you extract the kernels, you wonder why you bothered. The dry tidbit of food is a lot of starch and little sugar. Teosinte has 10 times more protein than the corn we eat today, but it was not soft or sweet enough to tempt our ancestors.

Over several thousand years, teosinte underwent several spontaneous mutations. Nature’s rewriting of the genome freed the kernels of their cases and turned a spike of grain into a cob with kernels of many colors. Our ancestors decided that this transformed corn was tasty enough to plant in their gardens. By the 1400s, corn was central to the diet of people living throughout Mexico and the Americas.

When European colonists first arrived in North America, they came upon what they called “Indian corn.” John Winthrop Jr., governor of the colony of Connecticut in the mid-1600s, observed that American Indians grew “corne with great variety of colours,” citing “red, yellow, blew, olive colour, and greenish, and some very black and some of intermediate degrees.” A few centuries later, we would learn that black, red and blue corn is rich in anthocyanins. Anthocyanins have the potential to fight cancer, calm inflammation, lower cholesterol and blood pressure, protect the aging brain, and reduce the risk of obesity, diabetes and cardiovascular disease.