NOW Foods Glucomannan 575 mg
NOW sells glucomannan from konjac root at 575mg per capsule, with a stated serving of three capsules taken one to two times daily. That is 1,725mg to 3,450mg a day, which lands squarely inside the range used in the published trials. The directions also specify 30 to 45 minutes before a meal with at least 8 oz of water — which is how the trials administered it.
Last reviewed · researched from the manufacturer’s published pages by Tom
What’s in it
Amounts are shown only where the manufacturer publishes them. Anything without a figure is undisclosed — and for an active ingredient, an undisclosed dose is the central problem with this category.
- Glucomannan (from konjac root)575 mg per capsule; 1,725 mg per 3-capsule serving
Single ingredient, no blend
How the manufacturer says it works
NOW positions it simply as glucomannan from konjac root at a stated milligram strength, with dosing directions rather than a weight loss promise. The product page leads with the specification, not the outcome.
What the evidence actually supports
Glucomannan is among the better-evidenced soluble fibres for satiety, with meta-analysed human data showing modest weight effects alongside a reduced-calorie diet. What makes this entry different from most of this directory is that the dose actually matches: three capsules give 1,725mg, and one to two servings daily reaches 1,725-3,450mg, against a research range of roughly 2,000-4,000mg. The timing instruction is equally important — taking it 30 to 45 minutes before a meal with water is precisely how the trials did it, because the point is for it to form a gel before the food arrives. Carries Intertek GMP Supplement certification, and 180 capsules at $26.99 makes it one of the cheapest properly-dosed options here.
Where that evidence stops
Effect sizes are still small — glucomannan trials typically report a couple of pounds over months relative to placebo, alongside a calorie-controlled diet. The safety point is the serious one: glucomannan expands substantially in water and taken without adequate liquid can swell in the oesophagus, with documented cases of obstruction. Three capsules is a lot of expanding fibre to swallow at once, and the 8 oz of water is not a suggestion. It is a fibre, not a GLP-1 mechanism.
Strengths and problems
Strengths
- The dose actually reaches the research range — 1,725mg per serving, 1,725-3,450mg daily against a 2,000-4,000mg research range
- Timing instruction matches the trial protocol: 30-45 minutes before a meal
- Specifies at least 8 oz of water, which is the critical safety instruction for a swelling fibre
- Single ingredient with a published per-capsule amount and a published serving size
- Intertek GMP Supplement certification
- $26.99 for 180 capsules is among the cheapest properly-dosed options in this directory
- The page leads with specification rather than a weight loss promise
Problems
- Three capsules per serving, one to two times daily, is a lot of capsules to keep up with
- Glucomannan swells and has documented oesophageal obstruction cases — the water instruction is genuinely load-bearing
- Effect sizes remain modest: a couple of pounds over months in the trials, alongside a calorie-controlled diet
- Not a GLP-1 mechanism despite the category
- Refunds and allergen information were not published on the page we captured
What the manufacturer publishes
Publishes 8 of 8 standard terms.
- Intended use
- Sold as a dietary supplement, not as a treatment for any condition.
- Directions
- Take 3 capsules 1 to 2 times daily with at least 8 oz of water, 30 to 45 minutes before a meal.
- Warnings
- Not fully published on the page we captured beyond the dosing and water instruction, which is itself the key safety point.
- Allergens
- Not published on the page we captured. Vegetarian capsules.
- Third-party testing
- Carries Intertek GMP Supplement certification — a manufacturing-practice certification covering the facility and process.
- Pricing
- $26.99 for 180 vegetarian capsules — 30 to 60 servings depending on whether you take one or two servings a day.
- Subscription
- Not stated on the page we captured. Discount codes for order thresholds were advertised at capture.
- Refunds
- Not stated on the page we captured.
- Shipping
- Free shipping on orders over $50 in the 48 contiguous states and DC.
May suit
Anyone who wants glucomannan at the dose and timing the research actually used, rather than a token amount inside a blend.
Do not use if
- You have any history of swallowing difficulty, oesophageal narrowing or bowel obstruction
- You will not reliably take it with a full 8 oz of water and stay upright afterwards
- You take medication that must be timed away from fibre — soluble fibre can impair absorption
- You struggle to swallow capsules — this is three at a time
Frequently asked
Why does this one stand out?
Because the dose and the timing both match the research. Most glucomannan in this directory sits inside a blend at a few hundred milligrams. Here a serving is 1,725mg, taken one to two times daily before meals with water — which is what the trials did. That does not make the effect large, but it makes the comparison fair.
Is the water really that important?
Yes. Glucomannan absorbs water and expands — that is the mechanism. Taken with too little liquid it can swell before it clears the oesophagus, and obstruction cases are documented in the literature. Take it with at least 8 oz of water and do not take it immediately before lying down.
Sources
Captured . Manufacturer pages change — check the current version before relying on anything.