Benefits
Less visible skin dryness and redness
In a 6-week randomized, placebo-controlled trial in 51 healthy adults, 100 mg a day of the konjac extract improved doctors' grading of skin dryness, redness, itching, uneven pigmentation and oiliness more than placebo. The trial was small, single-blind, used subjective grading without instrument measurements, and was run by the maker.
Skin water loss with oral plant ceramides
In a separate 12-week double-blind trial in 29 adults, ceramides and glucosylceramides from wine lees (not konjac) lowered water loss through the skin versus placebo, the main outcome, but did not change skin hydration, itch or skin-related quality of life. Whether konjac ceramides do the same is untested.
Plant-based glucosylceramide source
Konjac tuber provides glucosylceramides from a plant source; Skin-Cera is a hydroalcoholic extract standardized to 5% glucosylceramides.
Mechanism of action
Supporting skin ceramide content
Ceramides help maintain the skin's permeability barrier, and reduced ceramide content is linked to dryness. Dietary glucosylceramides are proposed to compensate for skin ceramide content, but neither cited trial measured skin ceramide levels.
Clinical trials
Single-center, single-blind, placebo-controlled randomized trial of 100 mg/day konjac extract (about 5 mg glucosylceramides) for 6 weeks, funded by the maker (Heggar Venkataramana et al. 2020, BMC Complement Med Ther).
51 healthy adults aged 18 to 60 enrolled; 40 completed.
Dermatologist-graded skin dryness, hyperpigmentation, redness, itching and oiliness decreased significantly more with the extract than with placebo, and no adverse events were recorded. The authors note the single-blind design and subjective outcomes as limitations; no instrument measures of hydration or water loss were reported.
Randomized, double-blind, placebo-controlled trial of oral ceramides and glucosylceramides from wine lees extract, a different plant source from konjac, sponsored by the manufacturer (Sanjaya et al. 2024, Nutrients).
30 healthy Japanese adults aged 20 to 64; 29 analyzed.
Transepidermal water loss, the primary outcome, was lower than placebo at 12 weeks (p = 0.04; not significant at 8 weeks). Skin hydration, itch and skin-related quality of life did not differ from placebo. No supplement-related adverse events.