11 Uses for Coffee Grounds You Didn’t Know About
From fertilizing your plants to fighting under-eye circles, coffee grounds can work wonders in your beauty routine and around your home.
Save your coffee grounds
Drinking a cup of coffee comes with a variety of health benefits, reducing inflammation to reducing your cancer risk. But after you’ve had your daily brew, don’t just toss those coffee grounds into the trash can—because they have health boosting benefits, too.
Add shine to hair and stimulate growth
Washing your hair is the best way to remove hair product buildup, but twice a month you should indulge your scalp with a deep clean as well. Make your own follicle facial by working brewed coffee grounds into your scalp with your fingertips for 60 seconds, rinse with cool water, and finish with your regular shampoo and conditioner. Over time, and with continued use, you’ll find that your hair is shinier, according to a 2014 study in the British Journal of Dermatology. You may even notice increased hair growth thanks to the stimulating effects of caffeine.
Deodorize your fridge
Prevent the smell of spoiled or overly fragrant foods in your refrigerator with coffee grounds. A study published in the Journal of Hazardous Material found that the nitrogen in coffee grounds helps neutralize odors. Simply fill a jar with used or fresh grounds and place it, uncovered, in the back of your fridge.
When you’re working in the garden, skip the commercial fertilizer and use old coffee grounds, instead. A study published in the Journal of Environmental Management, shows that so-called “spent” coffee grounds and charred spent coffee grounds absorb heavy metals that contaminate soil and water. “Commercial fertilizers contain nitrogen, potassium and phosphorous, but they also can contaminate groundwater with runoff and have other negative implications,” says Gwenn Fried, manager of horticultural therapy at NYU Langone Health, Rusk Rehabilitation, in New York City. “Coffee grounds used thoughtfully have similar benefits, are readily available, reduce waste, and smell good.”
Use it as a natural dye
Heads up, brunettes! Coffee grounds can be used to elevate the richness of your hair color without the use of harsh chemicals. Mix one teaspoon (or two, depending on the thickness and length of your hair) of cooled coffee grounds into a handful of conditioner and apply it to recently shampooed hair. Let it sit for no more than five minutes, and then rinse thoroughly with cool water to seal the hair cuticle. The temporary stain is not recommended for lighter hair colors.
Because of their grittiness, coffee grounds can be used as an effective DIY cleaning scrub. And since they may even help sanitize due to their antibacterial properties, they also lend themselves to home-made soap recipes. “I love to make kitchen soap with fresh grounds,” says Fried. “It’s great for washing up after a day of gardening or getting pesky cooking smells off of your hands.”
The same grittiness that makes coffee grounds an effective cleaning scrub makes it an effective exfoliant for your lips. At the first sign of chapped lips mix a half-teaspoon of used coffee grounds with a half-teaspoon of honey. Gently rub the mixture on your lips in a circular motion for 30 seconds, then remove with a wet washcloth. Following the at-home lip fix, apply an emollient balm to protect and nourish your pucker.
Fragrance shopping? Sharpen your sense of smell
Spraying and sniffing several fragrances on your quest to find the perfect scent can result in an inability to differentiate particular odors, also known as nasal fatigue. Although the science is inconclusive, conventional wisdom has it that smelling coffee can cleanse what’s known as your olfactory palate. Try it: On your next visit to the fragrance counter, or while sampling your own scents at home, bring a mug with coffee grounds and sniff to “reset” your sense of smell between spritzing samples.
Treat under-eye puffiness
Under-eye dark circles and puffiness—caused by genetics, allergies, fluid retention, or lack of sleep—are a common beauty complaint. To remedy the bags, apply chilled coffee grounds to your under-eye area, let sit for 10 minutes, and rinse well. A review of studies published in Journal of Cutaneous and Aesthetic Surgery showed that a caffeine-based gel helped diminish under-eye puffiness and dark circles. The anti-inflammatory properties in caffeine magically constrict the blood vessels, resulting in reduced under-eye swelling.
A study published in the journal Analytical Methods suggests that caffeic acid, an antioxidant in coffee, may boost collagen levels and reduce the premature aging of cells. But that’s only part of the reason aesthetician Jennifer Phillips includes coffee grounds in her DIY Chocolate Coffee Mask (see recipe below).
“I knew that caffeine could be a very effective ingredient to apply to the skin and what better way to utilize it than with coffee grounds,” says Phillips, creator of the natural lifestyle blog Jenni Raincloud. “Plus, I wanted to make a mask that would smell like a dessert, but would also deliver a good amount of antioxidants and hydration to the skin. I added clay so there would be a detoxing element to the mask.”
Combine the following ingredients, apply to the face and neck, and leave on for 10-15 minutes, or until the clay starts to stiffen. Using warm water, remove the mask in a circular motion. Follow up with a toner and cleanser.
- 1 tablespoon raw cacao powder
- 1 tablespoon bentonite clay
- 1 teaspoon fresh coffee grounds
- 1-3 tablespoons aloe vera gel (or water)
Since coffee grounds are rich in nitrogen, they’re perfect for an at-home compost. Just add the coffee grounds directly to your compost pile. How much? A study published in Waste Management showed that spent coffee grounds can be successfully composted in a variety of proportions. But researchers found that a batch containing 40% coffee grounds produced the lowest greenhouse gas emissions and best quality compost.
“In the home garden, I like to add used coffee grounds to compost that is ready to be applied to planters and garden beds,” Fried says. “I also will sprinkle used grounds directly around plants if I am trying to repel slugs. I’ve had some success with this pest repellent method, but it is not foolproof.”
Reduce the appearance of cellulite
About 80 to 90% of women have cellulite, according to a review of studies published in the American Journal of Clinical Dermatology. Although there is no permanent fix for cellulite, an exfoliating scrub made with coffee grounds (like the one below) can offer temporary results. A study published in Annals of Dermatology suggests that’s because caffeine is capable of stimulating the enzymes that break down fat, leading—possibly—to a reduction in cellulite. “Caffeine is known to not only brighten and tighten the skin but also to reduce the appearance of cellulite,” says Phillips. “Adding almond oil and salt help to remove dead skin and replenish moisture at the same time. This scrub leaves the skin feeling so soft and smooth!”
Combine the ingredients below, then use a brush or your hands to apply to cellulite-prone areas like the hips and thighs.
- 1 part sea salt
- 1 part coffee grounds
- top off with sweet almond oil
- 30 drops grapefruit essential oil
- 10 drops lemon essential oil
- British Journal of Dermatology: "Differential Effects of Caffeine on Hair Shaft Elongation, Matrix and Outer Root Sheath Keratinocyte Proliferation, and Transforming Growth factor-β2/insulin-like Growth factor-1-mediated Regulation of the Hair Cycle in Male and Female Human Hair Follicles in Vitro"
- International Journal of Dermatology: "Effect of Caffeine and Testosterone on the Proliferation of Human Hair Follicles in Vitro"
- Journal of Hazardous Material: "Spent coffee-based activated carbon: Specific surface features and their importance for H2S separation process"
- Journal of Environmental Management: "The effectiveness of spent coffee grounds and its biochar on the amelioration of heavy metals-contaminated water and soil using chemical and biological assessments"
- Gwenn Fried, manager of horticultural therapy at NYU Langone Health, Rusk Rehabilitation, in New York City
- Environment International: "The use of personal hair dye and its implications for human health"
- Agricultural and Food Chemistry: "Antibacterial Activity of Coffee Extracts and Selected Coffee Chemical Compounds against Enterobacteria"
- Perceptual and Motor Skills, "An Exploratory Investigation of Coffee and Lemon Scents and Odor Identification"
- Journal of Cutaneous and Aesthetic Surgery: "Infraorbital Dark Circles: A Review of the Pathogenesis, Evaluation and Treatment"
- Jennifer Phillips, aesthetician and creator of the natural lifestyle blog Jenni Raincloud
- Analytical Methods: "Caffeic Acid: a review of its potential use for medications and cosmetics"
- United States Environmental Protection Agency: "Composting at Home"
- Waste Management: "Effect of different rates of spent coffee grounds (SCG) on composting process, gaseous emissions and quality of end-product"
- Parasites & Vectors: "Coffee and its waste repel gravid Aedes albopictus females and inhibit the development of their embryos"
- American Journal of Clinical Dermatology: "Cellulite: An Evidence-Based Review"
- Annals of Dermatology: "Efficacy of Slimming Cream Containing 3.5% Water-Soluble Caffeine and Xanthenes for the Treatment of Cellulite: Clinical Study and Literature Review"