Does rosemary oil really work for hair growth?
Rosemary oil has a measurable effect on hormonal hair loss, comparable to minoxidil 2%, but less potent than conventional medications such as finasteride. It only works after six months, and scalp itching is a common side effect.
After six months of use, rosemary oil proved to be just as effective as minoxidil 2%, a common treatment for hormone-related hair loss, in a randomised trial with 100 participants. Both groups saw their hair counts rise significantly compared to the baseline measurement. After three months, neither group showed a visible effect yet, so patience is genuinely required.
One side effect to be aware of: both rosemary oil and minoxidil caused more scalp itching than before treatment. The rosemary group experienced less of this than the minoxidil group, but it is not a side effect that can be ignored.
When rosemary oil is compared with all available treatments at once, it scores lower than approved medications such as dutasteride, finasteride and minoxidil. It does perform better than doing nothing at all. Rosemary is therefore one of the few herbal remedies with some clinical backing, but it is not a replacement for standard treatments.
How rosemary works is not yet fully understood. In animal research, a rosemary extract inhibited the enzyme that converts testosterone into the substance that causes hair loss. In cell culture experiments, it increased a protein that may stimulate blood flow to the scalp. These are interesting clues about the mechanism of action, but they do not in themselves constitute clinical evidence.
The active compound carnosic acid, which is the subject of high expectations, dissolves poorly in common formulations. This is a practical obstacle to further development. More research in humans is needed before firm conclusions can be drawn about long-term effects and the optimal method of delivery.
The direct evidence in humans rests primarily on one randomised comparative trial with 100 participants, supplemented by a larger analysis that brought together 24 studies and places rosemary oil in perspective alongside other treatments. Several review articles confirm this picture, but emphasise that the total body of clinical research remains limited. Animal and cell culture research offers clues about the mechanism of action, but that is a different level of evidence from studies in humans.
Does resveratrol in skin cream actually do anything?
Resveratrol in skin cream demonstrably reaches the skin and has antioxidant activity, but whether it produces any visible effect as the sole active ingredient has not yet been proven. Combination products show promising results, but anyone buying a cream with resveratrol should be aware that the evidence for resveratrol itself remains thin.
Does castor oil work for your eyelashes and skin?
For eyelid inflammation and dark circles there are small positive studies, but the evidence is too thin for firm conclusions. The popular use for eyelash growth in healthy individuals has no clinical backing.
Do exosomes in skincare really work?
There are preliminary indications that exosomes may do something for the skin, but the clinical evidence is very thin: one small study without a control group and otherwise mainly animal research. Do not buy into the hype just yet, but keep an eye on the research over the coming years.
Does resveratrol really help protect cells against ageing?
Resveratrol protects cells impressively in the lab, but whether that also works in practice for you is uncertain: the body breaks the substance down quickly and large human studies are largely absent.
Can rapamycin reverse or prevent grey hair?
Rapamycin shows promising effects on grey hair in cell and animal research, but it has not yet been tested in humans. It is too early to use it for this purpose.
Does hyaluronic acid applied to your skin actually help against dryness and wrinkles?
Hyaluronic acid on your skin genuinely helps against dryness. Injections work most powerfully against wrinkles. A pill or powder adds little if you are already taking collagen.