While foraging has a lot of benefits, there are a few dangers to keep in mind too. There are a lot of delicious and edible foods out there, but there are just as many inedible foods and poisonous look a-likes. As a rule of thumb, you should never eat something you are not 100% certain of. Additionally, having two sources of identification is a good idea to reduce risk of misidentification. These sources can be a field guide, a reliable web source, or other foragers. Even when you are 100% sure of identification, some people still have sensitivities to foods they have never tried before. It is a good idea to eat with caution, and test how your body reacts to small amounts of your foraged goods. Once you know that you are not allergic, you can eat the rest in confidence.
Another thing to keep in mind while foraging is where you are sourcing your foods. Urban foraging is absolutely ok to do, but you should stray away from heavy foot trafficked areas, or areas that may be polluted with pesticides or natural metals. Just as toxins seep into the ground, they grow into the foods that come from the soil. If you take dandelion from a sidewalk where hundreds of people and animals walk everyday, it is likely that plant isn't suitable to be consumed.
Lastly, if you venture into the great outdoors, bring a buddy with you or be sure to not stray too far from the trails! It can be easy to lose track of the trail when you are on the hunt for the perfect chicken of the woods mushroom. Keep spatial awareness in mind as you forage to ensure you don't get lost in the woods.