By Jon Brown, RDN, B.S.
Edibility appears to be a black and white concept. Some things can be consumed, while others cannot. In reality, this concept is a little more complicated. Edibility may be related to the defense mechanisms of wild foods or our ability to digest certain ingredients. Physical and chemical defenses are important evolutionary features that are important for the survival of wild plants since they don’t have the ability to flee. These features may be able to give you clues about the edibility of a plant.
Poisons are compounds made by an organism as an internal defense to help the plant survive. If predators eat the poisonous plant, they will be harmed or learn to eat other plants. It is rare that a plant has both a physical and chemical defense, like poison. For example, thorny plants like raspberries and blueberries do not have a chemical defense. Nettles and thistles are quite heavily defended physically but are quite nutritious behind all the thorns and spikes. Not all spiky plants are edible. But it is rare for a plant to need both a physical defense like thorns and chemical defense. Some plants have neither a chemical defense nor a physical defense. But many plants with barbs or spikes are protecting nourishment. This is not just a local concept either. In the West, the prickly pear cactus is another example.
Sometimes humans simply have an intolerance for a certain food for any number of reasons. Metabolism varies quite wildly among animals and even among mammals. For example, some mammals can make vitamin C from sugar. Humans lack the enzyme that makes this conversion. There are some foods you shouldn’t feed your dog. If we absorb compounds our body cannot break down, it may reach toxic levels within our blood. In order to completely metabolize a product, we need to be equipped to fully digest all that it contains. If we lack the enzymes to break down a certain chemical, it can build up in the blood and potentially be toxic or cause an immune response within the GI tract. Common examples of these issues are seen in lactose intolerance and celiac disease. Intolerance can be influenced by genetics or environment.
When you’re out hiking, look and listen to the world around you. Look at what the birds and deer are eating. Maybe we share a common food, maybe we don’t. Does that plant have thorns? Maybe it’s protecting a rich and tasty food source. If you have a field guide and are looking to learn more about wild plants, these may be good places to start. Social media is another good tool to connect with wild food experts and lifelong foragers.
Jon Brown is a registered dietitian/nutritionist from Watkins Glen, currently working on his Master’s in sports nutrition at the University of Colorado Colorado Springs. He runs the Finger Lakes Foragers Club Facebook page, and enjoys foraging as a hobby. He has a private nutrition counseling practice, Fork in the Road Nutrition, and is looking to help individuals with their health and fitness goals.