Short answer: in cosmetics, "nano" describes an ingredient whose particles measure roughly 1 to 100 nanometres in at least one dimension. A nanometre is a billionth of a metre, about 1/80,000 the width of a hair. At that size a material can behave differently from the same material in bulk. It spreads more finely, disperses more evenly and handles light differently.
How is a nanomaterial defined?
The European Union writes it into law. Under Regulation (EC) No 1223/2009, a cosmetic nanomaterial is an insoluble or biopersistent, intentionally manufactured material with one or more external dimensions, or an internal structure, between 1 and 100 nm. EU ingredient lists have to flag it with "(nano)" after the name.
The U.S. FDA has no fixed legal definition. Its guidance on nanomaterials in cosmetics asks manufacturers to consider whether a material is engineered to have a dimension in the nanoscale range, or shows size-dependent properties up to one micrometre, and to assess safety for that specific material and use.
Where are nano ingredients already used?
You have almost certainly worn some. Mineral sunscreens use zinc oxide and titanium dioxide at nano size so they protect without the thick white cast. Mineral pigments, iron oxides included, can also be milled finer to change how they spread and feel.
Do nanoparticles get into the body through skin?
It is the question most people ask, and for insoluble mineral particles on healthy skin the reviews are reassuring. EU safety committees looked at nano zinc oxide and titanium dioxide and found the particles stay on the surface and in the stratum corneum, the outer layer of dead cells. They did not reach living tissue in meaningful amounts. Regulators still judge each nanomaterial on its own data, which is why ingredient choice, particle testing and manufacturing controls matter.
What does "nano" mean in SYLEKSA?
In SYLEKSA Nano Herbal Cream, "nano" refers to a hematite-derived iron oxide refined to the nano scale. It is a sensorial carrier. It shapes how the cream spreads and settles alongside the pressed clove, rosemary and lavender oils, so the finish is light and velvet rather than oily. Read what hematite is and how iron oxides are regulated, or see the full composition on our Science page.
SYLEKSA is a cosmetic for external use only. It is not intended to diagnose, treat, cure or prevent any disease.
The short version
- "Nano" means about 1 to 100 nm in at least one dimension.
- The EU defines cosmetic nanomaterials in law and requires "(nano)" on labels.
- The FDA reviews nanomaterials through guidance and case-by-case safety assessment.
- Insoluble mineral nanoparticles have been studied extensively on intact skin.
- In SYLEKSA, the nano mineral carries texture and feel. It is not a drug ingredient.
Frequently asked questions
Is "nano" just a marketing word?
Sometimes. A real nano ingredient has a measurable particle size in the nanoscale range, and in the EU it has to be labelled. Ask the brand which ingredient is nano.
Does nano mean more powerful?
No. Smaller particles change texture, spread and appearance. Size alone doesn't make a cosmetic do anything different inside your body.
Sources: Regulation (EC) No 1223/2009 on cosmetic products, Article 2(1)(k) and Article 19; U.S. FDA, Guidance for Industry: Safety of Nanomaterials in Cosmetic Products.