Sugar Stop is Co.Lab's carb blocker, sold by Partner.Co and by us. This is what is in it and what the evidence supports, which is narrower than the marketing.
What a carb blocker actually is
Starch is a chain of glucose molecules. Your body cannot absorb it as a chain, so an enzyme called alpha-amylase cuts it into pieces small enough to cross the gut wall.
White kidney bean extract interferes with that enzyme. Starch that is not broken down is not absorbed as sugar; it passes further along and is fermented by gut bacteria instead. That is a real, understood mechanism and it is the one serious idea in the product.
The same logic does not apply to table sugar, which is a much simpler molecule handled by a different enzyme. This is why the two figures in the marketing are different, and it is worth understanding rather than skipping.
About the percentages
The marketing states that it blocks up to 40 percent of sugar from starchy foods and up to 20 percent from table sugar.
Those are Partner.Co's figures. We do not have the substantiation behind them, so we are not going to restate them as our own. They are on this page as a description of what the manufacturer claims, not as a finding.
Two things worth knowing about numbers of this shape in general. "Up to" is doing work: it describes a best case, not a typical one. And blocking studies are usually done with a standardised starch load in a controlled setting, which is not lunch.
The ingredient list
- White kidney bean extract. The active idea, described above. - L-arabinose. A plant sugar that interferes with the enzyme handling sucrose. Same principle as the kidney bean extract, applied to table sugar. The human evidence is thinner. - 10 g of fibre. See below. - Tahitian noni. Present, and we are not going to tell you what it does here. The earlier version of this page attributed antioxidant and inflammation-related properties to it, which is not a claim we make about noni anywhere else on this site. Our actual position on noni is here.
The fibre is the underrated part
10 grams is a lot. Most adults in the United States get around 15 grams a day against a recommendation closer to 25 to 30, so a single serving here closes a meaningful part of a real and common gap.
Fibre slows how fast a meal is digested, which flattens the energy curve afterwards. It also fills you up. Neither of those is exotic and both are better established than anything else on the label.
If you took this product for the fibre alone, it would still be doing something. That is not how it is marketed, and it is probably the most useful sentence on this page.
Where the evidence gets thin, stated plainly
The original version of this article put this in the disclaimer at the very bottom. It was the most honest thing in it and it belongs in the body:
Carb blockers have reasonable short-term evidence and much weaker long-term evidence. They can reduce how much of a given meal's starch you absorb. Whether that translates into lasting weight change over months is a different question, and the answer from the research is not encouraging without other changes alongside.
There is also a practical consequence nobody mentions: starch that is not absorbed goes on to be fermented in the large intestine. For some people that means wind and bloating, especially early on. Starting with less than a full serving is sensible.
Who it is not for
- Anyone on prescription medication that affects how the body handles carbohydrate, without asking their doctor first. Interfering with absorption alongside a medicine that acts on the same thing is a conversation for a clinician, not for a label. - Anyone who already gets plenty of fibre and finds more uncomfortable. - Anyone expecting it to offset a diet rather than nudge one.
It is stimulant-free, gluten-free, soy-free and vegan, which is straightforwardly true and on the label.
The honest summary
A fibre supplement with a starch-blocking mechanism attached that has genuine short-term evidence behind it. Taken before a starchy meal it plausibly reduces how much of that meal you absorb, by an amount nobody has shown us the substantiation for.
If you want to see how we read Partner.Co's evidence across the range, that is Reading the Research.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
More on this subject: Weight Management