5.4
Green tea extract and chromium at doses that will not do much
$42/monthNot recommended
#4 of 12 overallSupplements
Fiberform Complete review
by Fiberform
Glucomannan and psyllium in a clinically plausible dose, third-party tested, sold without a single miracle claim. The effect size is modest and the company says so, which in this category is nearly unheard of.
8.2Recommended
Last updated · used for 12 weeks · reviewed by Tom
Disclosure: We have an affiliate relationship with Fiberform. If you buy through a link on this page we may be paid a commission, at no additional cost to you. We bought and used this product ourselves, and Fiberform had no involvement in this review, no advance copy, and no ability to change the score. Full disclosure
Tom’s verdict
I want to be clear about what I am recommending here, because 'best supplement on the site' is a low bar. Fiberform will not make you lose weight. What it does is take the edge off hunger at a cost of about eighty cents a day, with a real certificate of analysis and no lies on the label. In a category built almost entirely on lies on the label, that earns a recommendation — but a modest one, and you would get more from the same money spent on beans and vegetables.
What we liked and what we didn’t
Strengths
- Dose per serving is in the range actually used in published studies, not a fairy-dusted fraction of it
- Certificate of analysis from an independent lab published for every batch
- No proprietary blend — every ingredient has a stated quantity
- Marketing claims stay within what soluble fibre can plausibly do
- Cheapest credible option on the site at $24 a month
Problems
- The effect is small. Fibre helps with satiety; it does not do the work for you
- Must be taken with a full glass of water — a genuine choking risk otherwise, and the warning deserves more prominence than the label gives it
- Bloating and gas in the first ten days was significant for two of our three testers
- No fibre supplement is a substitute for eating vegetables, and this one costs more than doing that
Best for
Someone already eating at a deficit who struggles with hunger between meals and wants a low-risk, low-cost assist.
Not for
Anyone expecting a supplement to produce weight loss on its own, or with a history of swallowing difficulty or bowel obstruction.
What the evidence actually shows
Soluble fibre, glucomannan included, has a reasonable body of research supporting modest effects on satiety and small effects on body weight when combined with a reduced-calorie diet. Effect sizes in the published literature are small — typically a couple of pounds over several months relative to placebo. Fiberform's own marketing cites this literature accurately, which is why the evidence score is as high as it is.
The dose is the whole story
The most common trick in supplements is to include a real ingredient at a fraction of the studied dose, so the label is technically accurate and the product is inert. Fiberform does not do this. The glucomannan content per serving sits in the range used in the trials the company cites.
That is a low bar and it should not be remarkable. It is remarkable anyway, because most of the shelf fails it.
The safety warning deserves more prominence
Glucomannan expands substantially in water. Taken without enough liquid it can swell in the oesophagus, and there are documented cases of obstruction. The warning is on Fiberform's label, in small type on the back.
It should be on the front. We raised this with the company and were told it meets labelling requirements, which is true and is not the same as being adequate.
What’s in it
- Glucomannan (konjac root)
- Psyllium husk
- Microcrystalline cellulose
Ingredient lists are transcribed from the packaging at the time of testing. Formulations change — check the label you receive.
Others in supplements
2.6
A stimulant stack behind a proprietary blend and a pound-loss promise
$69/monthAvoid