Hello, and thank you for your question!
Purslane and sting nettles are both very nutritious. Purslane is rich in vitamin A and potassium and stinging nettles are rich in dietary fiber, calcium, and magnesium. For thousands of years, both have been used as food and medicine by many cultures. These foraged greens are also part of the traditional Mediterranean diet!
However, there are a few safety concerns with these foraged vegetables:
It can be dangerous coming in contact with the tiny stinging hairs on stinging nettle. To protect yourself, wear thick gloves or use tongs when handling raw nettles, and cook or steam them for 10-15 minutes to destroy the irritating compounds before eating.
Stinging nettles may lower blood sugar levels. If you have diabetes or need to control your blood sugar, consult with a qualified health professional before eating this plant.
Soils treated with pesticides may have high levels of heavy metals, which can be harmful to eat, and stinging nettles are particularly good at absorbing these heavy metals. It may be safer to gather nettles from your own yard, or wild areas (assuming that local laws permit foraging) rather than from a farm or orchard that may have used pesticides.
Generally speaking, as long as you are healthy and practicing food safety when picking and preparing purslane or stinging nettles (e.g. washing and cooking them thoroughly, etc.), it should be safe to eat moderate amounts of them regularly as part of a balanced diet.
In addition to purslane and stinging nettles, other colored vegetables (and fruits) can be part of a balanced diet. Check out our Lifestyle page and learn more about the benefits of eating a "rainbow" of colors.
Hope this helps!
- Anna, RD and Joshua, RDN
Hannah Bauman and Jenny Perez. “Food as Medicine: Stinging Nettle (Urtica dioica, Urticaceae).” HerbalEGram. July 2018. Available from <http://cms.herbalgram.org/heg/volume15/07July/FAM_Nettle.html>. Accessed September 8, 2020.
Jill Kohn. “Wild Greens.” Academy of Nutrition and Dietetics. January 9, 2018. Available from <https://www.eatright.org/food/planning-and-prep/snack-and-meal-ideas/dandelions-for-your-salad>. Accessed September 8, 2020.