For a few years there, niacinamide serums were locked in a quiet arms race. Ten percent, twelve, twenty — brands kept stacking the number higher as if concentration alone were the whole story, and plenty of users ended up with flushed, blotchy faces wondering why their gentle little vitamin was burning. Somethinc's Sabi Beet serum is interesting precisely because it refuses to play that game. It sits at 5%, and once you understand why, the rest of the formula falls into place.
The evidence on niacinamide actually supports the lower number. The studies behind its tone-evening and barrier-supporting reputation mostly used concentrations in the 2-5% range, and pushing past that buys you very little extra benefit while sharply raising the odds of irritation. So 5% here isn't Somethinc cutting corners — it's the brand choosing the dose that works without the sting. This is one of the few places in skincare where the number on the front of the bottle is inversely correlated with how much thought went into the back of it.
And then it goes a step further. Instead of plain water, the entire base of the serum is centella asiatica water, listed at a striking 72.5%. That means the soothing centella compounds aren't a token botanical near the bottom of the list; they're the carrier that everything else rides in on. Niacinamide delivered on a calming base is far easier on reactive skin than the same percentage in a bare aqueous serum, and swapping out water for something that does a job is a formulator's decision rather than a marketer's.
The 'Sabi Beet' part of the name points to the supporting cast. Beet root extract brings betalain antioxidants and a little moisture-binding sugar, and alongside it sits tetrahydrocurcumin — a colorless, stable derivative of turmeric that delivers antioxidant brightening without the yellow stain real turmeric would leave on your pillowcase. It's a clever inclusion: it complements the niacinamide's gradual tone-evening from a different angle, antioxidant rather than enzymatic. There's also a quiet dose of adenosine for a touch of smoothing and collagen support, plus chamomile, allantoin, caffeine, betaine, and vitamin E filling out the soothing-and-antioxidant theme. None of these are blockbuster actives on their own, but they're coherent — every addition supports the brightening-and-comfort brief rather than scattering in random directions, which is more discipline than most budget serums manage.
In use, it's a pleasure for a niacinamide serum. The texture is light and slightly slippy, sinking in fast to a soft, faintly dewy finish rather than the tacky film some niacinamide formulas leave. It's fragrance-free, with just a faint herbal note from the centella, and the hydration is genuinely noticeable — this is the rare niacinamide serum that leaves skin feeling more comfortable, not tighter. Most people will tolerate it from day one, though anyone who has never used niacinamide before should keep an eye out for mild warmth in the first few applications, and can sensibly start with once-daily use for a week before moving to twice.
On expectations, some calibration helps. Niacinamide works on pigment by interfering with the handoff of finished melanin from the cells that make it to the cells you can see. That is a slow, cumulative process — you're looking at three to four weeks for visibly more even tone and a couple of months for the fuller effect — and it collapses entirely if you skip sunscreen, since fading spots while manufacturing new ones at the same rate is the most common way brightening routines quietly fail. The serum is a foundation, not a spot corrector.
The limitations are modest and mostly about scale and pace. The 20ml bottle is small and empties in five or six weeks of twice-daily use, so the per-month cost is a little higher than the sticker suggests, though there's a larger 'Max' version for heavier users. And it's worth flagging that the polysorbate 20 and polyglyceryl laurate make it not strictly fungal-acne safe, which matters if you're managing malassezia. The beet and curcumin, for all their charm, rest on considerably lighter evidence than the niacinamide does; treat them as pleasant company rather than reasons to buy. None of these are dealbreakers; they're just the honest edges of an otherwise easy serum.
Where it really closes the deal is value. Somethinc is a young brand without the decades of clinical pedigree of a derm-developed label, but it isn't asking you to trust anything exotic — niacinamide at 5% is one of the most reliable actives in skincare, and the centella base is a smart, well-evidenced delivery choice. It's fragrance-free, alcohol-free, vegan, and pregnancy-safe, with nothing in it that argues with a retinoid or an acid used at the other end of the day. For a fraction of what comparable Western niacinamide serums cost, you get a gentler, more hydrating, thoughtfully built formula. If you want a brightening serum that won't fight your skin and won't dent your budget, this is a very easy yes.
