From a wearable mask to a Japanese fad diet, science is finding ever more uses for algae.

Inventors and designers Michael Burton and Michiko Nitta want people to think about algae. Specifically, how humans might be able to grow their own food on their own bodies by cultivating algae that thrive on CO2.

“Why design new food on what we have now, when we could re-design how we fuel the body altogether?” they ask on their website.

The goal of their continuing “algaculture” project is to harness the power of the sun combined with the carbon dioxide we exhale, to create food in much the same way plants do.

Last year, they debuted the “symbiosis suit,” a large mask of plastic tubes worn across the face, shoulders, and back. An opera singer performed with the mask on, and her large, gaping breaths fueled algae growth in the mask. Those in attendance were welcomed to drink the algae she produced.

The project is just one example of how people are discovering new uses for algae across the globe. It’s currently being developed as a biofuel and already appears in many consumer products.

Even if you’re not ready to wear a contraption that makes you look like a cross between Bane and the Predator, there’s no point in discounting algae as a food source. You’ve probably already eaten it already.

Agar, made from red algae, is used as a vegetarian alternative to gelatin and is found in jams, jellies, mayonnaise, processed cheese, creams, and frozen dairy products. It’s also the basis of a Japanese fad diet, which one study showed caused “marked weight loss” in obese people with type 2 diabetes when used along with a traditional Japanese diet.

Seaweed is a type of algae that has been eaten by island cultures for centuries. It’s rich in important vitamins and minerals, including calcium, iodine, iron, magnesium, and potassium.

Most algae and seaweeds are high in omega-3 fatty acid, an essential nutrient with numerous proven health benefits, including reducing cholesterol and improving heart health. While humans get most of their omega-3s from seafood, concerns about sustainability have some companies exploring seaweed and other algae as a more viable source of nutrients.

Aurora Algae is developing a sustainable protein that can be used by athletes and people who need to lose weight, as well as a plant-based source of omega-3 fatty acids.

Solazyme has used algae to develop ingredients for packaged foods that are healthier than standard ingredients, such as eggs, butter, and vegetable oil. By using their products, the company states, manufactured food can be lower in calories, saturated fat, and cholesterol.

Face masks or no, these entrepreneurs are putting plants to good use.