NOW Foods Glucomannan 575 mg Review
#1 of 8 · Best Overall✓ Label verified · Supplement Facts read Sep 7, 2026Real retailer photo, cut out. Label unedited.
Buy it if you want the capsule whose label matches how glucomannan was actually tested. Glucomannan's evidence is modest and specific: grams of fiber in capsules, with a full glass of water, before meals.
$16-18~$0.28 per 3-capsule serving (1.725 g)
Why It Scores 8.8 — And The Label Line Behind Each Number
Dose vs the Trials
30% of score1.725 g of declared glucomannan per serving, one to two times daily before a meal, lands inside the 2 to 4 g a day range the reviews describe; the 575 mg capsule splits easily.
- Per serving
- 1.725 g glucomannan (from konjac root)
Label Directions & Safety
20% of scoreAt least 8 oz. of water, 30 to 45 minutes before a meal, and a printed caution about swelling in the throat, blockage and choking.
- Directions
- 3 capsules 1 to 2 times daily with at least 8 oz. of water, 30-45 minutes before a meal
Testing & Manufacturing
20% of scoreGMP Quality Assured seal on the label and Intertek GMP certification shown in the gallery; quality tested in the USA; no third-party potency statement printed.
- Seals
- GMP Quality Assured, Non-GMO, vegetarian/vegan
Formulation & Form
15% of scoreHypromellose capsule with hydroxypropyl cellulose, silicon dioxide, microcrystalline cellulose and stearic acid; vegetarian and vegan.
- Form
- Veg capsule (hypromellose)
- Other ingredients
- Hypromellose, hydroxypropyl cellulose, silicon dioxide, microcrystalline cellulose, stearic acid (vegetable source)
Value
15% of scoreAbout $0.28 per 1.725 g serving; mid-pack per gram, well below the branded diet pill.
- Serving
- 3 capsules
- Count
- 180 capsules (60 servings)
- Cost per dose
- ~$0.28 per serving
Label verified. Every figure read from the Supplement Facts photo, Sep 7, 2026.
Marketing Claims Vs. Reality
575 mg, from konjac root.
The panel declares 1.725 g of glucomannan per three capsules, which is 575 mg a capsule.
Healthy weight management.
The label ties it to satiety within a diet and exercise program, which is fair. On its own, glucomannan did not produce significant weight loss in the 2014 meta-analysis (Onakpoya) or in the 2013 Rush University trial (Keithley).
Supports healthy cholesterol levels already within the healthy range.
A 14-trial meta-analysis found glucomannan lowered total and LDL cholesterol (Sood 2008).
What Our Test Actually Found
The label is the product
Every capsule on this list holds the same fiber. What separates them is whether the bottle tells you how to take it safely and in the pattern the trials used. NOW prints the dose, the water, the timing and the choking caution; several cheaper bottles print a serving size and little else.
In-house testing, not third-party
NOW's GMP certification is real and its lab programme is extensive, but the label carries no third-party potency statement. That keeps the testing score below the two brands that print one.
Full analysis: all pros & cons (7), buy if / skip if
- 1.725 g of declared glucomannan per serving
- Water, timing and choking caution printed
- Vegetarian capsule, GMP-certified brand
- Dose splits before two meals
- Three capsules per serving
- No third-party testing statement on the label
- Four excipients
- You want a pre-meal fullness aid with the directions printed correctly
- You want a vegetarian capsule from a GMP-certified brand
- You want to split the dose before two meals
- You expect weight loss from the capsule alone; the pooled trials did not find it
- You have any swallowing difficulty or esophageal narrowing
- You dislike taking three capsules at a time
Glucomannan's evidence is modest and specific: grams of fiber in capsules, with a full glass of water, before meals. NOW gives you 1.725 g per serving once or twice a day, says so in those words and prints the choking caution. It is vegetarian, GMP-certified and costs about twenty-eight cents a serving. The honest limit is the fiber, not the bottle: the best recent trial and the 2014 meta-analysis found no significant weight loss.
NOW's bottle does the three things a glucomannan label should. It declares the fiber itself, 1.725 g of glucomannan from konjac root per three veg capsules, rather than an extract weight. It prints the trial-style routine: three capsules one to two times daily with at least 8 oz. of water, 30 to 45 minutes before a meal. And it carries the caution that matters for this fiber: without enough liquid the product may swell in the throat and cause blockage or choking. The capsule is hypromellose; the 180-count bottle holds 60 servings.
The glucomannan to buy: right dose, right directions, right warning
If you want to try glucomannan the way it was studied, this is the bottle that tells you how. Take three capsules with a full glass of water half an hour before your biggest meal, never dry and never lying down, and treat it as a fullness aid inside a calorie deficit rather than a fat burner.
If This Doesn’t Fit — Try These
02NOW Pure Powder
If you are disciplined about stirring half a teaspoon into a full glass of water and drinking it straight away, NOW's powder gives you the studied fiber for pennies.
03Nature's Way 1,995 mg
Nature's Way gets the dose, the directions and the warning right and adds almost nothing to the fiber.
04Best Naturals 2-Pack
If you already know glucomannan agrees with you and want months of it cheaply, this two-pack is the sensible purchase.
Quick Answers
How many NOW Glucomannan capsules is a dose?
Three capsules, 1.725 g of glucomannan, one to two times daily with at least 8 oz. of water, 30 to 45 minutes before a meal. That is the label's own direction and it sits inside the 2 to 4 g a day the reviews describe.
Will glucomannan make me lose weight?
Probably not on its own. An early eight-week trial reported a 5.5 lb loss (Walsh 1984), but a larger 2013 trial found no difference from placebo and a 2014 meta-analysis of eight trials found no significant weight loss. It can help you feel full before a meal; the deficit still has to come from the plate.
Sources & Further Reading
2 peer-reviewed sources, each linked to PubMed
- [1] Keithley J, Swanson B. Altern Ther Health Med. 2005;11(6):30-4. PMID 16320857 — Glucomannan and obesity: a critical review. A critical review concluding that at 2 to 4 g per day glucomannan was well tolerated and produced significant weight loss in overweight and obese individuals, probably by promoting satiety and fecal energy loss, while calling for further safety and efficacy trials.
- [2] Onakpoya I, et al. J Am Coll Nutr. 2014;33(1):70-8. PMID 24533610 — The efficacy of glucomannan supplementation in overweight and obesity: a systematic review and meta-analysis of randomized clinical trials. A meta-analysis of eight randomized trials found a non-significant difference in weight loss between glucomannan and placebo (mean difference -0.22 kg); adverse events included abdominal discomfort, diarrhea and constipation.
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