INGREDIENT · PLANT OIL
Macadamia oil in skincare: what the small studies show
Macadamia oil is sold as a rich, quick-absorbing oil. The two studies we found on what it does tested it in specially made nano-sized creams, which is not what most bottles are.
You may see it written as
- Macadamia Ternifolia Seed Oil
What the two studies tested
A 2024 study first screened several natural oils for antioxidant and anti-hyaluronidase activity in the lab, and picked macadamia oil as the most potent. It was then formulated into a conventional emulsion and a nanoemulsion. Neither caused irritation in a hen's-egg membrane test and a clinical test, and both enhanced skin hydration and reduced wrinkles in volunteers, with the nanoemulsion best for hydration.1 The 2024 study used oil from Macadamia integrifolia, and we cannot say that every label’s macadamia oil is the same species.1
A 2019 study compared a 10% macadamia oil nanocream with a conventional cream over four weeks, using a skin analyser to measure moisture, evenness, pore size, spots and wrinkles. The authors report the nanocream showed better anti-ageing activity.2 With three volunteers per cream, moisture and pore size differed significantly between the creams; wrinkles and spots did not.2
How to read this
Both studies tested macadamia oil in engineered formulations, so they say little about a bottle of plain macadamia oil. Neither study tested the same cream without the oil, so we cannot say how much of the effect came from the oil. Both are small, and the 2019 study's cream also contained other ingredients.1,2
What the safety review found
In 2017 the Cosmetic Ingredient Review expert panel assessed 244 plant-derived fatty acid oils together. It noted they are used for skin-conditioning, occlusive, emollient and moisturising properties, and because many are edible with low systemic toxicity, it focused on possible effects on the skin. It concluded the 244 oils are safe as used in cosmetics.3 The panel was set up in 1976 by the cosmetics industry’s trade association, with support from the US Food and Drug Administration and the Consumer Federation of America.4
That is a conclusion about the group of oils. It says nothing about how well macadamia oil works, which is the question the two studies above try to answer.
Using macadamia oil with other products
The studies tested macadamia oil within a formulation, not layered with other products.1,2 We did not find a source on layering.
Macadamia oil in pregnancy and breastfeeding
We found no pregnancy- or lactation-specific evidence for this ingredient.
Evidence on cosmetic products in pregnancy is limited overall, so ask your doctor or midwife about the specific product you use.5
What you will see on the label
On a label, look for Macadamia Ternifolia Seed Oil. Snifff shows it as Low risk. For the rest of the formula, see what the score means and how to read the list.
As Snifff shows itMacadamia Ternifolia Seed Oil
Pregnancy and nursing
We found no pregnancy- or lactation-specific evidence for this ingredient.
Wording as it appears in the extension, which can change between releases.
A FEW MORE ANSWERS
Common questions about macadamia oil
Is macadamia oil good for skin?
Two small studies of macadamia oil in nano-sized creams reported better hydration, and only the 2024 study found fewer wrinkles. Neither tested the plain oil.1,2
Does macadamia oil irritate skin?
In a 2024 study, macadamia nanoemulsions caused no irritation in a membrane test or a clinical test.1
Is macadamia oil safe on skin?
A 2017 expert-panel review of 244 plant-derived oils concluded they are safe as used in cosmetics.3 It assessed the oils as a group.
Is macadamia oil safe in pregnancy?
Snifff found no pregnancy-specific evidence for Macadamia oil. Ask your doctor or midwife about the product you use.
WHERE THIS COMES FROM
Sources
- Clinical efficacy in skin hydration and reducing wrinkles of nanoemulsions containing Macadamia integrifolia seed oilSomwongin S, Chaiyana W · Nanomaterials · 2024
- Macadamia nuts oil in nanocream and conventional cream as skin anti-aging: a comparative studyHanum TI, Laila L, Sumaiyah S, Syahrina E · Open Access Macedonian Journal of Medical Sciences · 2019
- Safety assessment of plant-derived fatty acid oilsBurnett CL, Fiume MM, Bergfeld WF, Belsito DV, et al. · International Journal of Toxicology · 2017
- Fifty years of the Cosmetic Ingredient Review (CIR) and the Expert Panel for Cosmetic Ingredient Safety: an independent, transparent, and science-forward program for ingredient safety assessmentInternational Journal of Toxicology · 2026
- Cosmetic dermatology in pregnancy and lactation: a risk-benefit framework for clinical practiceKovacs T, et al. · International Journal of Dermatology · 2026
This page explains an ingredient. It is not medical advice, and it is not an assessment of any product. If you are pregnant, breastfeeding, or have a skin condition, ask your doctor or pharmacist.