01 Nov 2025
So what is the difference between a bio and non-bio laundry detergent?
It all comes down to enzymes.
Bio detergents contain enzymes that break down common stains like food, sweat, grass and grease. They’re your grime-fighting little helpers.
Non-bio detergents don’t contain enzymes. Which makes them a gentler option for sensitive skin.
So while bio is a powerhouse for stain removal, non-bio keeps things calm, clean and kind.
BIO | NON-BIO | |
CONTAINS ENZYMES? | Yes | No |
GREAT FOR STAINS? | Yes, especially food, sweat and grease | Yes, but may need warmer water |
SENSITIVE SKIN? | May irritate some skin types | Gentler on sensitive skin |
BEST TEMPERATURE | 20 to 40 | Often needs 40 |
BEST FOR... | Stain removal | Babies, eczema, sensitive skin |
how enzymes help clean your clothes.
Enzymes in bio detergent target specific types of dirt:
- Amylase breaks down starchy stains like pasta, potatoes and cereal.
- Lipase tackles oily and greasy marks (butter, body oils, takeaway splashes).
- Mannanase breaks down food thickeners (found in baby food, sauces, ice cream).
- Cellulase keeps fabrics looking newer by smoothing fibres and preventing greying.
- Deoxyribonuclease targets sweat, body odour, and helps prevent yellow armpit stains.
Enzymes are most effective in 20 to 40°C washes because anything hotter and they start to break down (and not in a good way).
why choose non-bio detergent?
Because sometimes skin doesn’t like enzymes.
Non-bio detergent skips the enzymes entirely, making it a popular pick for:
- Baby clothes
- Sensitive skin, eczema, psoriasis or contact dermatitis
- Those who prefer less fragrance (hello, fragrance-free capsules!)
And don’t worry. Non-bio can still clean brilliantly, especially if you bump the temperature a little.
so, which smol detergent should you choose?
Bio liquid or capsules for the power cleaners:
- tackles the tough stuff (food, sweat, odours)
- works wonders at lower temperatures
- lower chemical concentrations than leading brands
- vegan, cruelty-free, smart little capsules
Non-bio liquid or capsules or even non-bio fragrance-free capsules for the gentle touch:
- dermatologically tested
- loved by parents, eczema sufferers and fragrance avoiders
- kind to sensitive skin but still super effective on dirt
- also vegan and cruelty-free
bio vs non-bio FAQs.
is bio or non-bio better for the environment?
Both smol bio and non-bio are designed to be better with lower chemical concentrations, less packaging, and lower carbon impact than leading brands.
does non-bio clean as well as bio?
Non-bio is still excellent at general cleaning but for tougher stains, bio often has the edge thanks to its enzymes.
can I use bio detergent on baby clothes?
Yes, but if your baby has sensitive skin, it’s safer to stick with non-bio.
why does bio work better at lower temperatures?
Because enzymes are temperature-sensitive and if the water is too hot they get denatured (a fancy word for: they stop working properly).
do smol laundry capsules contain bleach?
Nope! smol bio and non-bio are bleach-free to protect your fabrics and your colours.
Catherine Green, Cleaning Expert
Catherine has been on a mission to revolutionise the way we tackle chores since the dawn of smol is an advocate for making more sustainable living accessible to all with a strong focus in cleaning that’s heavy on dirt, lighter on the planet. Catherine has tested hundreds of hacks to make tackling chores easier, safer, and better for the planet.
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