People can use coffee grounds for many different things, from garden fertilizers and skin scrubs to cleaning products and flea repellents.
Coffee grounds are left over after a person brews coffee. They are usually considered a waste product but can be useful.
A person can get coffee grounds from brewing coffee at home or from coffee shops that are giving them away.
Learn more about the many uses for coffee grounds in this article.
Coffee is a beverage brewed from roasted coffee beans. Coffee beans grow in around 80 countries in South and Central America, the Caribbean, Africa, and Asia, and people all over the world consume the beverage.
According to the International Coffee Organization, people consumed more than 166,000 bags of coffee (weighing 60 kilograms [kg] each) worldwide in 2020–2021. The United States accounted for over 30,000 of these bags.
Coffee grounds can be useful in several ways. The sections below look at some of these in more detail.
Skin exfoliation product
People can mix coffee grounds with water, honey, or coconut oil to create a skin scrub that they can use all over the body.
Exfoliation removes dead cells from the top layer of the skin and can unclog pores, clean the skin, and reduce acne. It may also make the skin look brighter and reduce the appearance of fine lines.
Coffee has a strong color, and coffee grounds can dye natural fabrics to different shades of tan and brown.
One 2019 study found that coffee grounds are a potential natural dye for use on a commercial scale, as the fabrics the researchers dyed in the study stayed colorfast to industry standards.
People can also use coffee grounds to dye their hair, though they may not produce a significant color change or last for a long time. That said, they may be suitable for a short-term change.
According to the American Cancer Society, research has not been able to confirm whether or not commercial hair dyes cause cancer. However, some chemicals present in some hair dye products may have the potential to cause cancer.
Plants need nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur to grow. Coffee grounds can conserve the nitrogen content of soil, which may benefit plant growth.
One 2019 study found that mixing coffee grounds into soil improved the nutritional value of lettuce.
However, a 2016 study found that coffee grounds slowed down plant growth but retained moisture in the soil and reduced weeds. This study also suggested that more research is necessary to confirm the benefits of using coffee grounds as fertilizer.
Coffee contains diterpenes, which
One 2018 study concluded that although coffee grounds were not toxic to ants, it was an effective repellent against them.
Coffee may also be an effective method of mosquito control, as a 2015 study found that mosquitoes were less likely to hatch if coffee was present in their environment.
Fleas also do not like coffee grounds. Because of this, a person might be able to try rubbing coffee grounds into their pet’s fur if they have fleas.
However, before doing so, they should check with a vet to make sure that this method of flea prevention is suitable for their pet.
Caffeine is toxic to cats and dogs, so people should be careful not to let their pet eat coffee grounds. Caffeine poisoning can cause symptoms within around 30 minutes and be fatal.
Coffee grounds are a coarse powder. This means that they are abrasive and that people can use them to scrub surfaces, utensils, or appliances that have ingrained or hard-to-remove dirt.
That said, coffee grounds may be too rough to use on delicate surfaces or utensils.
The caffeine in carbonized coffee grounds can eliminate odors by absorbing hydrogen sulfide molecules from the air.
As a result, people can make coffee grounds into soaps to neutralize odors on the hands after cooking, for example, or to minimize odors in shoes.
Meat tenderizers use enzymes to break down fibers in meat to make it softer and easier to eat. Meat tenderizing powders use acids and enzymes from fruits such as pineapple and papaya.
Coffee grounds are acidic and contain enzymes that can also break down fibers in meat, so a person can try using coffee grounds to soften meat before cooking it.
A person can also marinate the meat in coffee or use coffee grounds as a meat rub to add flavor.
Furniture restoration product
A person can also use the strong color of coffee to restore scratched wooden furniture.
After mixing coffee grounds with water, a person can rub the resulting paste into scratches on wooden furniture to match the original color.
According to the Institute for Scientific Information on Coffee, the diterpenes in coffee grounds, such as cafestol and kahweol, can raise a person’s cholesterol.
However, the amount of diterpenes in coffee will depend on how a person brews it. Filtered coffee does not contain as many diterpenes as unfiltered coffee, such as coffee made in a French press.
Drinking excessive amounts of coffee
Coffee is rich in many nutrients and has numerous health benefits, from anticancer activity to antioxidant action.
The antioxidants in coffee grounds include phenols, which help fight free radicals that can harm the skin.
Coffee also has antibacterial properties, according to one
Coffee may also help reduce cellulite, as a
Some people may be more sensitive to caffeine than others, so recommended daily allowances may vary.
Coffee grounds are a waste product from the coffee brewing process. Around 1.5 kg of coffee grounds are produced per kg of soluble coffee, which means that there are a lot of coffee grounds left over after brewing coffee. People usually throw these away as waste.
However, people can make use of leftover coffee grounds by making them into a skin scrub, natural dye, or garden fertilizer. They can also try using coffee grounds as an insect repellent or household cleaner.
A person should not consume coffee in excess. They also should not let their pets or other animals eat coffee grounds, as they can be toxic.