Organic Silk Sheets and Peace Silk: Are There Benefits?

If you’ve ever slept on silk sheets or with a silk pillow, you’ll know how luxurious this can feel. The cost of genuine silk sheets might make you think twice, though, about decking out your boudoir with silk. And, if the cost doesn’t trouble you, the ethics might, given that the manufacture of a single silk neck tie can require around 150 silk worms to be boiled alive in their cocoons. To make a pillow case or silk comforter, the death toll is much higher. Is there such a thing as ethical silk? Let’s take a look.

The deadly downside of silk production

Silk sheets sure feel good, but most are fraught with ethical issues. In conventional silk production, cocoons made by silkworms on silk farms are put in boiling water before the worm breaks out of the cocoon (which would cut the thread). The worms are then boiled alive as silk farmers unravel the cocoon to produce a continuous thread that can measure as much as 500 meters in length. 

This type of silk is typically known as Mulberry silk and comes from many generations of inbreeding of silkworms for commercial purposes. Such inbreeding has resulted in silkworm moths that are too heavy and disfigured to fly or even move naturally, and the farming practices result in significant suffering and premature deaths of the moths. 

Some estimates suggest that the average necktie requires 50 grams of silk, for which you would need to boil around 150 worms in their cocoons. For a sheet, pillowcase, or silk comforter, the death count would be significantly higher, of course. For me, this is far too high a price to pay for the kind of luxury I can achieve from high-quality organic cotton sheets. 

What’s the alternative, then? Well, you might want to check out something called ‘peace’ silk.

Is ‘peace’ silk really ethical?

A few years ago, at an arts and crafts market while on vacation, I stumbled upon a company selling clothing made with so-called ahimsa or peace silk. They claimed this silk was sourced without harming silkworms and was ethical and just as good quality as Mulberry silk. Skeptic that I am, I did some digging to find out if these claims could be substantiated.

Peace silk, also known as Tussah silk, is, indeed, harvested after the silkworms emerge from the cocoon. No silkworms are boiled alive, and this kind of silk is typically harvested from cocoons in the wild, rather than from farmed silkworms. 

Because the silkworms have already chewed a hole in the cocoons, ahimsa silk threads are much shorter than that one long Mulberry silk thread. All this means, though, is that Tussah silk threads have to be spun together to create a single longer thread. The yield is also lower per cocoon, but the spun yarn is softer, stronger, and more like linen than silk. 

All in all, if the cocoons of silkworms are harvested in the wild and the silk is not treated with toxic dyes, the resulting silk could be considered a sustainable eco-friendly fiber, especially as silkworms feed on mulberry leaves, meaning that there is little energy input (although considerable water input) involved in silk production.

The benefits of silk sheets

From a comfort and longevity perspective, silk can be a great choice for sheets. This fiber is a natural temperature regulator, so is a good option if you live somewhere with dramatically shifting temperatures throughout the year. With proper care, silk can also be very durable, lasting some 15-20 years; this makes it quite eco-friendly and, if you consider the cost of replacing lower quality sheets, rather economical too.

Silk fibers can be bleached by hydrogen peroxide and can be dyed with all classes of dyeing agents, meaning that there’s no need to use harsh chemicals to color silk. Unfortunately, toxic azo dyes and other chemicals are frequently used in silk processing. 

As for the purported health benefits of silk sheets, these may be no more than rumors that ought to be put to bed. While silk sheets are often heavily marketed for being hypoallergenic and having benefits for your skin and hair, there’s little to support such claims.

The reasoning behind these claims is that silk contains certain amino acids which are the building blocks of proteins called fibroin and sericin. These proteins make up the central core of silk threads in the cocoon. 

Sericin is a natural polymer that acts like a glue to join two fibroin filaments in silk threads. It contains 18 amino acids, including essential amino acids, and has been touted as having antioxidant, moisturizing, healing, antitumor, and antibacterial and antimicrobial properties as well as protecting against ultraviolet radiation (R). Sericin is even being investigated for its potential use as a cognitive enhancer in Alzheimer’s disease (R).

Sounds great, right?! All you need to do is sleep on silk sheets and you’ll enjoy fantastic health for life. Not quite. There’s no real indication that any kind of amino acid transfer occurs between skin and silk when you sleep on silk sheets. What’s more, if it did, you could hardly call silk hypoallergenic as the potential for allergic reaction is usually linked to an abnormal immune response to proteins, i.e. chains of amino acids. 

There’s also another problem with the idea that you can get all the benefits of sericin from sleeping on silk sheets: In textile manufacture, sericin is largely removed from the cocoon in a process called degumming. The remaining fibroin is converted into raw silk, which is then used to produce yarns and silk fabrics. This process may involve the addition of other types of chemical adhesive to glue the fibroin filaments together.

What happens to all that sericin? Sadly, it’s mostly discarded in wastewater, resulting both in the loss of a useful resource (a natural adhesive) and potential contamination of the environment. Estimates suggest that around 25-30% of the raw materials in a cocoon are wasted during silk processing (R). This amounts to many thousands of tons of sericin discarded every year worldwide.

The disposal of sericin in wastewater generates a high chemical and biological oxygen demand and contaminates that water [8]. Silk production typically requires a large amount of land, water, and the use of chemical fertilizers and pesticides. Finding a better way to produce and process silk could have significant social, economic, and environmental effects in countries where sericulture is serious business, such as China, India, Japan, and Brazil.

Wild harvested peace silk has many potential benefits for the environment and for health, both for the silkworms themselves and for humans. Those workers who process the silk have less exposure to chemical fertilizers and pesticides, and the rest of us can enjoy a cleaner environment overall. That’s because land is not being stripped and monocultured to grow the mulberry bushes that feed silkworms. Instead, wild mulberry plantations support greater biodiversity, protect soil and waterways, and provide work in smaller communities, especially in India and China, where almost all silk is produced.

Where to find ethical silk sheets

If you’re considering buying silk sheets, look for those that are naturally dyed and from a sustainable source. If a company can demonstrate its commitment to harvesting wild silk and avoiding the use of toxic chemicals during processing, great. 

When looking for silk products, in addition to determining whether the silk is cruelty-free, you may also want to keep an eye out for terms such as charmeuse and momme. Charmeuse is a type of weaving style that creates silk sheets with a shiny and a dull side. Momme is the measure used for the weight of 100 yards of silk (1 momme (m/m) = 4.3056 g / square meter). This measure ranges from 6-30. Silk sheets that are assessed around 19 momme are a good option in terms of affordability, quality, and strength.

Some types of silk are machine washable on a delicate cycle, while others need to be dry cleaned (which normally involves toxic chemicals). If washed, silk should be dried by ironing while damp as it tends to wrinkle and stiffen if line dried.

Sadly, it seems that there’s rather a lack of eco-friendly, ethical silk sheets. I’d love to hear from you if you’ve tracked down any such sheets, but in the meantime would point you towards the Ethical Silk Company’s silk pillowcases which are made with peace silk.