Is Eggshell Biodegradable? (9 ways to utilise eggshells) 

In this article, it shall be explored whether egg shells are biodegradable or not. Various related topics such as what is biodegradability and why is biodegradability important shall be discussed and analysed. Also, the various disposal methods and utilisation alternates of eggshells would be gone through. The medical benefits of eggshells will also be deliberated and finally, the frequently asked questions related to the topic would be discussed and deliberated. 

Is Eggshell biodegradable? 

Yes, eggshell is biodegradable. Eggshell is made up of natural substances which are calcium carbonate and proteins. When it comes to biodegradability, the rule of thumb is that natural materials can easily be biodegraded. 

Other than biodegradation, eggshells can also be discarded and utilised in a plethora of ways which shall be discussed in the later sections. However, it is important to note that eggshells, despite being biodegradable and reusable; are not recyclable.

What is an eggshell? 

An eggshell is the outermost part of an egg which is mostly made up of calcium carbonate. The function of the eggshell is to provide conformity, structure and barrier to the inner contents of the cell. eggshells may contain up to 20,000 pores. 

The structure of an eggshell is mostly porous which implies that air and water (in the form of moisture) can pass through. The eggshell has a semi-permeable membrane to allow for the passage of materials. 

It is notable that the rigidity of the eggshell is subtly balanced; strong enough to protect the inner contents but brittle enough to let the chick get outside. While most of the eggshell is made of calcium carbonate, it also contains proteins in very small amounts. 

These proteins are responsible for how the remaining Calcium Carbonate will crystallise. The nano-scale structure analysis unveils that the combination of proteins and mineral crystals is precisely optimum in eggshells. 

What is biodegradation?

Biodegradation can be defined as the process through which complex materials are broken down into simpler materials through various mediators (time, microbes) so that those simple materials may be consumed leaving no wastes. 

With the increased impacts and strain on the environment, the check of whether a material is biodegradable or not has become more important than ever. If a material is biodegradable then it implies lesser waste and hence lower strain on the environment. 

However, if a material is not biodegradable readily, it will take hundreds of years for that particular material to degrade. In that case, the strain on the environment and solid waste management will increase tenfolds. 

When it comes to biodegradability, the rule of thumb is that man-made materials such as plastics et cetera are not biodegradable since they are synthetic. They accumulate in the environment such as water bodies, and disposal sites and toxicate the environment.

However, naturally occurring material which does not contain any synthetic elements can readily biodegrade within months and hence would not cause any strain to the environment or the waste management authorities. 

Why is the biodegradability of eggshells important? 

It may be a matter of piqued interest why the biodegradability of eggshells is important. The immense use of eggs makes the biodegradability of eggshells important. 

In the UK alone, the consumption of eggs is flabbergasting. As per the statistical analyses, it is found that the average egg consumption for the year 2021 in the UK was 13.5 billion eggs. This implies that each day almost 37 million eggs were consumed in 2021 in the UK. 

Another factor that makes the subject important is that not only the consumption of eggs is immense but it is also increasing which is logical given the population rise in context. 

As per the stats, the consumption of eggs in the UK has increased by 3 billion eggs each year since 2006. In the last 13 years, there has been an increase of more than 50% in the retail of commercially available eggs. 

The increased use of eggs asserts that more and more eggshells are left to discard and dispose and that is why it is important to know if eggshells are biodegradable or not. With that, the right disposal methods of eggshells are also important. 

How should eggshells be disposed of? 

It is important to know what are some ways through which the right disposal of eggshells can be achieved. Simply throwing away eggshells in the garbage cans will not be a good choice environmentally. 

To be able to dispose of eggshells in the right way, it is important to know what are some of the best ways through which eggshells can be utilised. 

Since eggshells are biodegradable, they can be composted. Eggshells can also be composed at home by using some simple steps including: 

  • Wash the eggshells
  • Dry the eggshells 
  • Make smaller pieces of eggshells by using pestle-like tools
  • Mix the smaller pieces of eggshells in the soil 
  • Or add the mixture to a compost 

Eggshells can not be recycled since they are made of natural materials and hence it will be unwise to dispose of eggshells in recycle cans. 

Eggshells given their contents can also be used as fodder for chicken as a source of calcium carbonate and some proteins. However, it is important to first crush the eggshells. 

Eggshells can also be employed for organic gardening because they contain high amounts of calcium carbonate. Other than that, eggshells can also be used for aesthetic purposes to make your garden look better. 

What are some of the best ways to utilise eggshells?

A better approach than just disposing of eggshells would be to know what are some of the creative and innovative ways to utilise and reuse eggshells. Below are some of the ways in which eggshells can be utilised better: 

  • As eggshells contain calcium carbonate, they can be used as food for chickens to complement their calcium carbonate needs. 
  • Eggshells can also be used as a sweetener for coffees. For this, boil the eggshells and add it to your coffee. 
  • Eggshells can also be consumed by humans to give a good source of calcium. For this, create a powder of eggshell and add that to your drink. Or you can make a broth of eggshells.
  • Eggshells can also be added to apple cider vinegar to improve the benefits of it. Apple cider vinegar is used for a variety of purposes such as washing the hair and face. 
  • Eggshells after freezing can also act as a knife sharpener
  • Eggshells can also be used for aesthetic purposes to improve the overall look of your garden, sidewalk or gallery. 
  • Eggshells can also be used to treat skin irritations. For this, add eggshells to apple cider vinegar and apply to the skin 
  • Eggshells can also be used as a garden fertiliser because of their contents of calcium carbonate 
  • Eggshells can also be used to treat muscle and joint pains. For this, let eggshells dissolve in apple cider vinegar for a day or two and then apply to areas with pain. 

How Eggshells can be a Nutritional Source?

Since eggshells contain high amounts of calcium carbonate, proteins and some other organic compounds; eggshells are a great source of calcium. It has been assessed through various studies that eggshells can prove to be a great calcium supplement. 

It was also revealed in some studies that the uptake of calcium through eggshells was greater and more effective as compared to other options. It is also suggested that calcium uptake with eggshells as a source is better than purified calcium supplements. 

Other than calcium, eggshells are also a source of other minerals including magnesium, fluoride and strontium which are vital for bone health. 

How Eggshells can treat osteoporosis?

Osteoporosis is a medical condition that involves the weakening of bones and an increased risk of fracture. This may be caused by a number of factors such as old age, and poor nutrition; however inadequate uptake of calcium is the underlying reason behind osteoporosis. 

Osteoporosis affects a large population of people annually. Millions of people are affected by the negative impacts of osteoporosis which results in being unable to walk properly and other medical conditions. 

This can be avoided by taking eggshells as a source of calcium which has been proved to be a better option as compared to calcium supplements because of increased uptake. Eggshells can also improve bone mineral density and 

Eggshells may be made into a powder to be added to the drinks. Broth of eggshells can also be made to be enjoyed as a good and effective calcium source. 


It is concluded that eggshells are made up of natural materials (majorly calcium carbonate) and proteins and that these materials can easily biodegrade within a short span of time. Since eggshells are biodegradable, they do not cause greater harm to the environment. 

It is also concluded that despite being biodegradable, eggshells are not recyclable. However, eggshells can be used in a variety of ways thus saving the environment and the economy as well. No tradeoff here! 

It is also concluded that eggshells have high amounts of calcium contents which make them a good fit as a carbon source for plants, animals, and humans. Eggshells can also be used as fertilisers while also giving numerous medical benefits. 

Frequently Asked Questions: Is Eggshell Biodegradable? 

Is Eggshell a green waste? 

Yes, eggshell is a green waste since it contains natural compounds like proteins and calcium carbonate which can be degraded. You must place eggshells in the green waste cans so that the right actions can be done to this green waste. 

Is eggshell harmful to the environment? 

Eggshells may be harmful to the environment if they are not disposed of in the right way. If eggshells are not discarded properly, they may accumulate for up to up to three years without giving any benefit. 

However, if eggshells are discarded in the right ways they may be reused and utilised in a variety of ways including food for plants and animals, medicinal sources and aesthetic purposes. 

Is eggshell edible? 

Yes, eggshell is edible and appears to be a great source of calcium for plants, animals and even humans. Eggshells can be made into a powder to add to our drinks or can be added to a broth to serve as a rich source of calcium. 


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