Fried, scrambled, poached, and boiled, eggs are an incredibly versatile food that are packed with vitamins, minerals, protein, antioxidants, and omega-3 fatty acids.
Although the yolk and whites are usually the reason we crack open an egg, the eggshell itself is truly a marvel of Mother Nature.
Composed of 95% of calcium carbonate crystals, the eggshell is covered with as many as 17,000 tiny pores that allow air and moisture to enter the inner egg. The outermost layer of the shell has built in protection, called the bloom or cuticle, which prevents dust and bacteria from getting inside. Between the shell and the egg proper is a transparent membrane, made up of proteins that also aid in defense against foreign contaminants.
The next time you eat eggs, you might want to hang on to the shell. Here’s why.
4 Brilliant Benefits Hiding In Your Eggshells
1. Eggshells are an Excellent Source of Calcium
Calcium is necessary for maintaining healthy bones throughout our lives. This is especially true for children in order to reach their full adult height and adults over 50 who are more at risk of developing osteoporosis.
The recommended daily amount of calcium for men and women aged 19 to 50 years old is between 1,000 mg and 2,500 mg. After the age of 50, women should be getting 1,200 mg to 2,000 mg each day.
Our bodies do not produce calcium and so we must consume calcium rich foods like dairy products and dark leafy greens. For the body to absorb calcium, we also need to ensure we are receiving enough vitamin D.
Because eggshells are almost entirely calcium carbonate, half of one eggshell provides 1,000 mg of calcium – enough to meet the daily requirements for adults.
Compared with calcium supplements that are derived from seashells and limestone, eggshells have been shown to be superior to these sources, enhancing calcium absorption by 64%. The added calcium transport in eggshells are due to matrix proteins found within the shell.
2. Eggshells Strengthen Bones & Improve Bone Mineral Density
Bones are living tissue that, throughout our lives, are continuously being broken down and replaced. When older bones are removed at a faster pace than they are replaced, bones become very brittle and weak. Over time this can lead to osteoporosis, a disease characterized by low bone mass and the deterioration of bone tissue. It is dubbed the ‘silent thief’ since osteoporosis develops without signs or symptoms, and often isn’t diagnosed until after a break or fracture.
In a bit of good news for osteoporosis sufferers, a 1999 study found that a diet enriched with chicken eggshells, vitamin D, and magnesium had the effect of increasing bone mineral density in a short period of time. All of the study’s participants had been diagnosed with osteoporosis; half of which took 300 grams of eggshell powder, 400 IU of vitamin D, and 400 mg of magnesium, while the rest served as a control group. Measuring bone mineral density via X-rays, the eggshell group experienced a median increase of 4.4%, with some seeing their bone mass rise by nearly 16% over 4 months. This group also reported less pain and an improvement in overall well being.
On the other hand, the control group whose diets remained unchanged experienced even further bone erosion over the same period. By the 8 month mark, this group saw their bone mineral density degrade by around 1%.
3. Eggshells Help Remineralize Teeth
A dental cavity begins when oral plaque becomes acidic. When we consume sugary foods and drinks, the bacterial plaque in our mouths converts the sugars into acids which dissolve (or demineralize) the tooth enamel.
When the tooth is demineralized, it releases calcium and phosphate into mouth saliva. The calcium and phosphate minerals in saliva will help neutralize the acids to remineralize your teeth. It’s a natural process to prevent tooth decay. But when too much sugar is consumed too often, the remineralization action is stunted which may allow bacteria to enter the tooth and cause a cavity.
Because eggshell powder is so rich in calcium, it can be used to help along the remineralization process. In a study published in 2015, sample teeth were first demineralized and then immersed in an eggshell powder solution for seven days. Compared to the untreated tooth samples, eggshells enhanced remineralization and raised pH levels to neutralize tooth enamel eating acids.
4. Eggshells Relieve Pain & Inflammation in Joint Disorders
The eggshell membrane is the thin yet strong transparent layer that lies between the shell and the egg white. Composed of keratin, collagen, glucosamine, and several other compounds, it has been shown to offer relief from painful joint and connective tissue disorders like arthritis.
The 2009 study evaluated the effects of taking 500 mg of eggshell membrane on people who suffer from painful joints, reduced flexibility, and decreased cartilage. After seven days of treatment, joint pain was significantly reduced while flexibility and range of motion had vastly improved. Nearly half of the participants were entirely pain-free after 30 days of treatment.
How To Safely Prep Eggshells
While you can purchase eggshell calcium capsules, collecting eggshells from the eggs you eat is really easy, reduces waste, and is practically free.
To start, rinse out cracked eggshells and set them out to dry completely. For quicker drying, you can bake them in the oven for about 10 minutes at 150°F. Once dry and brittle, grind them up with a mortar and pestle, in the blender, or a coffee grinder. The consistency should be powdery; you can remove larger fragments by sifting. Store your eggshell powder in a container with a good sealing lid.
To extract the eggshell membrane, simply peel it off of the eggshell. This video shows just how easy it is to do.
How to Eat Eggshells + 12 Other Uses Around the Home & Garden
To supplement your diet with eggshells, just add a ½ teaspoon of powder to food or drink to receive around 500 mg of calcium carbonate. Be sure to take calcium along with sources of vitamin D (sunlight, milk, egg yolks, cod liver oil, tuna, etc.) to boost absorption.
Because eggshells are basically flavorless, you can add them to your favorite foods without altering the taste. Eggshells will, however, affect the texture of foods. A study on this topic found that the best foods to add eggshell powder to are bread, pizza, and pasta. Eggshell powder can also be added to bone broth, smoothies, fruit juices, and coffee.
Beyond eating, eggshells have an abundance of worthy uses around the home and in the garden:
1. Add it to the Compost – Toss some of your eggshell supply in the compost heap to increase calcium levels in the finished humus.
2. Chicken Feed – If you keep backyard chickens, you can feed them slightly crushed shells to boost their calcium intake.
3. Add to Bird Seed – You can also sprinkle some crushed eggshells into your bird feeder to bump up the nutritional value of bird seed. This is especially beneficial for wild birds during the height of egg laying season in springtime.
4. Seedling Pots – Eggshells make for excellent tiny “pots” to grow plants from seed. Here’s a tutorial on how to do it.
5. Enrich Your Soil – Add eggshell powder to your potting soil mix for your indoor plants, or work it directly into your garden soil for outdoor varieties.
6. Feed Your Tomatoes – Tomatoes are susceptible to blossom-end rot, which is caused by a calcium deficiency. To fix and prevent, apply powdered eggshells around the base of the plant and work into the soil.
7. Pest Control – Sprinkle crushed eggshells to make a barrier around your garden plants to deter pests like slugs and snails.
8. Use it on Your Skin – Calcium plays an important role in skin growth and regeneration, regulating how quickly dead skin cells are replaced. Skin that is deficient in calcium can appear aged before its time. To use eggshells in your skincare regimen, add it to your favorite facial mask recipe and let it sit on your face for about 15 minutes before rinsing away.
9. Eggshell Body Scrub – You can also add eggshell powder to homemade body scrubs for extra exfoliation.
10. Remineralizing Toothpaste – If you make your own toothpaste (and here’s why you should!), add in some eggshell powder to protect and repair tooth enamel. Here’s a great starter toothpaste recipe.
11. Add Eggshells to Your Cleaning Products – As a natural abrasive, you can add crushed eggshells to your dish soap and scouring powders to enhance grit.
12. Add it to Pet Food – Our furry friends can certainly benefit from bone and connective tissue support. Thoroughly mix in finely ground eggshell powder and / or egg membrane into their wet foods.