Supergut Prebiotic Shakes review

Our take: the best-evidenced Supergut product, still oversold

Supergut’s Prebiotic Shakes are a powdered meal replacement: mix a serving with water or milk and you get about 15 g of prebiotic fibre (20 g in Mocha Latte), 15 g of protein, about 1 g of sugar and 26 added vitamins and minerals. That is half a typical adult’s daily fibre target in one glass.

They also have the strongest claim to evidence in the Supergut range. The company’s 2023 randomised trial tested a fibre-enriched meal-replacement shake in people with type 2 diabetes, and blood sugar control improved. No other Supergut product is as close to what was tested.

The problems are the label on the front and the calories in the glass. Listings sell the shakes as “Boost GLP-1”, but that trial did not measure GLP-1 or appetite. And at about 90 kcal a serving mixed with water, a shake is far too light to be a meal on its own.

This is a desk review. We have read the published label details, retailer listings and the research on the ingredients. Nobody on our team has drunk these shakes, so we say nothing about taste or texture. We could not open Supergut’s product page while writing, so the next section says where each figure came from.

What exactly are you buying?

Supergut sells the shakes in six flavours, in 8- and 14-serving packs. Per serving, listings give:

Listings give about 90 kcal and 1 g of sugar a serving for the dairy flavours mixed with water. The Chocolate 14-serving pack weighs 826 g, about 59 g a serving, and the 472 g (16.6 oz) Chocolate canister pictured works out at about 8 servings on the same serving size. The canister front also claims to “Boost GLP-1”, “Control cravings” and “Manage weight”. We could not confirm the full panels for the vegan flavours, or whether Mocha Latte contains caffeine, so we leave those out rather than guess.

The dairy versions are built in blends:

• Milk protein concentrate: the protein source, giving 15 g of complete protein.
• Supergut Resistant Starch Fiber Blend: soluble maize fibre, green banana resistant starch, resistant potato starch and oat beta-glucan — the same four fibres as the fibre powders and bars, in undisclosed amounts.
• Sweetener blend: allulose and rebaudioside M (a stevia-derived sweetener). Unlike the bars, the listings we read name no erythritol.
• Creamer blend: high-oleic sunflower oil, acacia fibre, xanthan gum and guar gum.
• Flavourings and a vitamin and mineral blend of 26 nutrients.

The vegan flavours replace the milk protein with a plant protein; we could not confirm which.

Prebiotic Shakes or “GLP-1 Boosting” Shakes?

You may see these shakes under two names. The original 14-serving bags are sold as Prebiotic Shakes, with “Boost GLP-1” in retailer titles. Newer 8-serving packs in Chocolate and Vanilla are sold as GLP-1 Boosting Prebiotic Shakes, sometimes shortened to GLP-1 Booster Shakes.

On every listing we could read, the figures are the same: 15 g of prebiotic fibre, 15 g of protein, about 1 g of sugar and about 90 kcal a serving. We found no study of the renamed pack, so the new name adds a claim, not evidence — everything in this review applies to both. One retailer listing of the 8-serving Vanilla pack also names brown rice protein alongside milk protein, which may mean a small recipe change; we could not confirm it, so check the ingredient list on the pack you buy.

Do not confuse these shakes with Supergut’s GLP-1 Daily Support, a fibre powder that was also sold as “GLP-1 Booster”. It has 6 g of fibre a scoop and no protein.

What the evidence shows

The trial is the closest match in the range

In the Frias 2023 trial, adults with type 2 diabetes took two packets a day of a fibre-enriched nutritional formula, with at least one replacing a meal, for 12 weeks. HbA1c — a measure of average blood sugar — fell by 0.64 points more than with placebo, and quality of life improved. That is a meaningful change for people with diabetes.

Three caveats matter. The trial was in type 2 diabetes, not in healthy people buying a shake for gut health. It used two servings a day, not one. And we could not confirm that the formula tested is identical to the one on sale today.

Fibre and protein are well supported

A 2019 series of meta-analyses in The Lancet found people eating 25 to 29 g of fibre a day had lower rates of heart disease, stroke, type 2 diabetes and bowel cancer. Guidance is similar around the world: the World Health Organization advises at least 25 g a day, and US dietary guidelines advise about 14 g per 1,000 kcal, roughly 25 to 34 g for most adults. One shake covers about half. Protein and fibre together are also the two nutrients most consistently linked to feeling full.

The GLP-1 claim is not

Fermentable fibre can nudge GLP-1 up a little, but the Supergut trial did not measure it. A 2026 scoping review of 52 studies found fibre-driven GLP-1 rises showed only a non-significant tendency towards feeling fuller. And the resistant-starch trial that produced weight loss used 40 g a day of resistant starch alone — more than two shakes’ total fibre. As our GLP-1 Daily Support review explains, none of this is comparable to GLP-1 medicines.

Is it really a meal replacement?

Not on its own. At about 90 kcal with water, a shake gives less energy than a banana. A meal replacement that you rely on should give a meaningful share of a day’s energy and protein; this gives a good share of fibre and a modest amount of protein, and little else.

Mixed with milk, or drunk alongside a piece of fruit or a slice of wholegrain toast, it makes a reasonable light breakfast. Replacing two meals a day with shakes on water would leave most adults well short of energy, and should only be done with medical supervision.

The 26 added vitamins and minerals also mean that anyone taking a multivitamin should check the combined amounts, especially if they drink two shakes a day.

Sweeteners and tolerability

A serving holds 15 to 20 g of fermentable fibre — more than most people’s guts are used to at once — plus allulose, which is poorly absorbed and can cause wind and loose stools in larger amounts. Starting with half a serving for a week or two, and building up, is sensible.

The dairy flavours contain milk. Fibre can slow the absorption of some medicines taken at the same time, and people with diabetes who take glucose-lowering medicines should speak to their clinician before replacing meals, because a lower-carbohydrate meal can change what they need.

Price: per shake and per gram of fibre

In listings read on 28 September 2026, an 8-serving pack was $14.99 on Amazon.com with an on-page coupon, against a usual listed price of about $30. That is about $1.87 to $3.75 a shake, or $0.12 to $0.25 per gram of fibre. We could not confirm a current price for the 14-serving pack, so check it against the same sums.

That makes the shakes the cheapest way to buy Supergut’s fibre — cheaper per gram than Foundational Daily Fiber (about $0.21 to $0.25) and the bars (about $0.23 to $0.33) — and you get the protein too. But a scoop of plain whey or plant protein with a bowl of oats or beans still costs far less for the same fibre and protein.

Supergut is sold across the US — on its own store, Amazon.com and at retailers including Walmart, Target, GNC and Vitamin Shoppe. Outside the US, its help centre says it ships to most countries with some products restricted, and some local retailers stock part of the range in other countries. If you are ordering from abroad, add international postage and any import charges to the dollar price before comparing it with shakes sold where you live. We read the US prices from listings rather than taking an order through checkout.

Best alternatives

The ones we have fully reviewed are linked, and appear in the comparison cards below this article. The others we name for comparison only: we have not reviewed them in full, so do not read their inclusion as a recommendation.

• A protein shake with fibre from food — a plain protein powder blended with oats, or drunk alongside beans, lentils or fruit, gives the same fibre and protein for much less.
• Supergut Foundational Daily Fiber (reviewed) — the same fibre blend without the protein, with honest claims. The better pick if you only want fibre.
• Supergut Prebiotic Bars (reviewed) — 10 g of fibre and 10 g of protein as a snack, at a higher price per gram of fibre and with erythritol.
• Supergut GLP-1 Daily Support (reviewed) — the same four fibres as a powder, with the same unsupported GLP-1 framing.

Who should skip it

Skip the dairy flavours if you have a milk allergy, and skip the shakes if allulose or large amounts of fibre upset your stomach. Anyone with diabetes on glucose-lowering medicines should talk to their clinician first, and anyone on regular medication should check spacing with a pharmacist.

And skip them if you want a complete meal in a glass, or are buying for GLP-1 or weight loss: they are too light for the first, and the evidence does not support the second.

Claims on meal replacements and supplements are the manufacturer’s responsibility; regulators in most countries, including the US FDA, do not approve them for effectiveness before sale.

Sources and shopping: our checklist

Before you buy, check the panel for your flavour, the delivered price per shake, and what else you will eat with it. If you try them, start with half a serving and build up over a week or two.

Our commercial link for this product is our Supergut Prebiotic Shakes link. It earns us a commission at no extra cost to you, and it has no influence on the score above — which is a 5.2, second in the Supergut range behind Foundational Daily Fiber (5.4), held back by a GLP-1 framing the evidence does not support, an undisclosed fibre blend and too few calories to replace a meal on its own.

The fair summary is this. Supergut’s shakes are the best-evidenced product in the range and the cheapest per gram of fibre: a light, high-fibre, high-protein drink. Buy them for that, alongside food — not for GLP-1.