"I grew up eating wild purslane soup," says Rosemary Gladstar, founder of the California School of Herbal Studies in Forestville, California, and author of Herbal Healing for Women. "My grandmother made it for us as a kind of all-over tonic. She cooked the purslane with other plants, like amaranth and chickweed, then added some onions and garlic. It was powerful medicine."
Gladstar's Armenian grandmother may have relied on intuition and observation to feed her family, but science eventually backed her up: Purslane is now known to be especially rich in vitamins A, B, C, and iron. It's also among the best plant sources for omega-3 fatty acids, the essential fats that may reduce the risk of coronary heart disease and could increase the activity of white blood cells, which attack germs in the body. In general, purslane, which is not widely grown commercially in the United States, but can sometimes be found at Mexican produce stands or farmers' markets, acts as an immune-boosting supplement to any diet. Thanks to her grandmother, says Gladstone, 58, "I knew, even as a young girl, that plants could heal."
The truth is that long before researchers proved that certain plant foods contain the vitamins and phytonutrients that promote a healthy immune system, grandmothers (and other cooks) the world over figured out that some foods help bodies fight illness better than others. As a result, traditional foods and folk recipes often feature immune-boosting ingredients. Garlic, nature's best-known antibacterial food, shows up in soups from Spain to Thailand to Louisiana. Fermentation, which creates beneficial bacteria that support digestive health, is a technique that has brought about such foods as yogurt, miso, and sauerkraut (developed by the Chinese centuries before it was a German staple). My Russian grandmother favored borscht—a marriage of beets, cabbage, carrots, onions, and stock—so thick with brightly colored veggies that it could easily be called antioxidant soup.
And in my childhood home, the classic folk remedy, chicken soup—affectionately known as Jewish penicillin—was doled out at the first hint of a sniffle. Lo and behold, decades later a team of researchers at the University of Nebraska found that chicken soup may relieve the miseries of a cold—though not cure it. (It's interesting to note that the lead scientist conducted his initial research using a veggie-laden recipe handed down by none other than his wife's grandmother.) The study found that, whether it's homemade or canned, chicken soup helps inhibit the release of mucous. And the scientist jovially added that just knowing someone went to the trouble of cooking a pot of soup for you might make you feel better!
More and more, it seems, the scientists and the world's grandmothers are in agreement about the health-giving powers of certain foods. So to get ready for winter, I'm arming myself with research and anecdotes about healing soups filled with veggies, herbs, and spices that boost immune function. With two boys in germ-laden grade school and the first chilly days upon us, I can only do what any sensible grandmother would suggest: Make soup!