Nutrition · Flours & Starches

Potato Starch: Benefits, Uses, Substitutes & Raw vs. Cooked

What potato starch is, how the raw powder feeds the gut bacteria that make butyrate, what human trials show for regularity and blood sugar, why heat removes its resistant starch, and how to use it, cook with it and swap it.

By Dr. Josh Axe, DC, DNM, CNS·19-min read

Meet the Medical Advisory Board

Evidence-based36 sources citedUpdated October 29, 2026

Published Oct 29, 2026Last updated Oct 29, 2026Editorial policyMedical review policyFact-checking policy

Potato starch is the starch extracted from potatoes, a fine white powder with almost no flavor.

The Dr. Axe Score™

6.0/10

Overall Dr. Axe Score · Potato Starch

Potato starch scores 6.0 as a prebiotic you take raw, an easy, everyday way to feed your gut bacteria, with human trials behind it for butyrate, regularity and fasting blood sugar in older adults.

Scientific Evidence

5.6/10

Five human studies of raw potato starch itself, in 10 to 174 people over a single meal to 12 weeks (two funded by a maker), plus pooled reviews of resistant starch and animal studies.

Bioavailability & Absorption

6.2/10

It isn't absorbed by design: raw, half or more of it escapes digestion and reaches your colon intact for your bacteria to ferment, and cooking turns it into ordinary, digestible starch.

Clinical Effectiveness

5.0/10

An easy everyday prebiotic, with more butyrate in 2 weeks, fewer hard stools at about a teaspoon a day and lower fasting blood sugar in adults over 70.

Safety & Tolerability

7.6/10

Mild gas or bloating, mostly at higher amounts and in the first weeks; potato allergy is rare.

Why this score?

Why Potato Starch scores 6.0 / 10

Weighting: Evidence 30% · Bioavailability & Absorption 25% · Clinical Effectiveness 25% · Safety & Tolerability 20% (5.6×0.30 + 6.2×0.25 + 5.0×0.25 + 7.6×0.20 = 1.68 + 1.55 + 1.25 + 1.52 = 6.00, shown as 6.0). How we score

A transparent, weighted index built for foods. See how it’s calculated →

Interaction check: Low. No drug interactions have been documented for potato starch, and none was reported in its human trials. Interactions are rated separately and don't change the score.5 1

Dr. Josh Axe · Free quiz

Cellular Health Quiz

Loading question one…

Potato starch at a glance

Potato starch is the starch extracted from potatoes. Raw, it's one of the richest sources of resistant starch you can buy: food for the bacteria in your colon that make butyrate, the fuel your colon lining runs on.1 2 3

What it does: in human trials, raw potato starch raised stool butyrate 29% in 2 weeks, cut down on hard, lumpy stools at about a teaspoon a day and lowered fasting blood sugar in adults over 704 5 1
How much: a tablespoon holds about 6 to 8 grams of resistant starch; start with 1 teaspoon a day and build over 2 to 3 weeks toward 1 to 2 tablespoons6 2 7
How to use it raw: stir it into something cold, such as water, a smoothie, coconut yogurt or goat milk kefir, because heat turns it into ordinary starch8
In the kitchen: it's a naturally gluten-free thickener for gravies, soups and pie fillings, and 2 teaspoons does the work of a tablespoon of cornstarch9

Potato starch is the starch extracted from potatoes, a fine white powder with almost no flavor. Raw, it's a resistant starch: half or more of it escapes your digestive enzymes, so it travels to your colon and feeds the bacteria that make butyrate. Cooked, it's a gluten-free thickener for gravies, soups and baking.1 8 4 9 So the same bag in your pantry can do two very different jobs, depending on whether you heat it.

Feeding those bacteria matters because low fiber intake, antibiotics and chronic stress are, in my view, the three biggest things destroying the gut microbiome,10 and when the bacteria that make butyrate go hungry, the cells lining your colon lose their main fuel.3 Resistant starch is one of the simplest ways to feed them, because it travels all the way to your colon, where those bacteria are waiting to eat. Here's how I explain it on my show:

You eat fiber or resistant starch. These are things you can't digest on your own, so the bacteria go and ferment them in your colon.Dr. Josh Axe, DC, DNM, CNSFrom The Shocking Reason Your Anxiety, Brain Fog & Bloating May Start in Your Gut, The Dr. Josh Axe Show (2026), at 12:43

Get the free Healing Leaky Gut Protocol

Feeding your gut bacteria is the Reinoculate step of this free 30-day protocol, and it goes slow and gentle with prebiotics while your gut heals. Inside:

The 6R roadmap: Remove, Replace, Reinoculate, Repair, Rebalance and Reframe
Which prebiotics to start with while your gut heals, and which to save for later
The foods that heal, plus a 7-day meal plan

Free with your Dr. Axe account (email or Google). You'll also get the protocol's short email series and the Dr. Axe newsletter; unsubscribe anytime.

Open the free protocol →

Did you know?

Potato starch granules are four to five times larger than cornstarch granules, which is why a smaller amount makes a thicker sauce.9
The Nutrition Facts label on potato starch lists 0 grams of fiber.6 Yet half or more of the raw powder escapes digestion and reaches your colon, where your gut bacteria eat it.2
On Passover, Ashkenazi custom avoids corn as kitniyot, while potatoes aren't kitniyot, which is why potato starch stands in for cornstarch in so much Passover cooking.11

What is potato starch?

Quick answer

Potato starch is the starch extracted from potatoes and dried into a fine white powder. It's nearly pure carbohydrate, naturally gluten-free, and while it's raw, half or more of it is resistant starch.1 6 2

Starch is how a potato stores energy, packed into tiny granules, 15 to 100 micrometers across. About 80% of potato starch is amylopectin, a branched starch molecule, and about 20% is amylose, a straight chain.1 In the raw powder, those granules are tightly packed, a little like a sealed lunchbox, and that keeps your digestive enzymes out, which is why so much of it reaches your colon intact.1 8

Unlike whole potatoes or potato flour, potato starch carries almost none of the potato's fiber, protein or potassium, as the nutrition table below shows. You'll also see two kinds of potato starch on the shelf. Modified potato starch is a processed-food ingredient, treated so it behaves differently in packaged foods (the FAQ has more on it).12 Raw, unmodified potato starch is the plain powder used in the gut trials and in home kitchens, and it's the one to bring home.1

Potato starch nutrition

Quick answer

A tablespoon of potato starch (12 grams) has 40 calories and 10 grams of carbohydrate, with no fat, protein, sugar or fiber listed on its label. While it's raw, about 6 to 8 grams of that tablespoon is resistant starch.6 2 4

Per 100 grams, from USDA FoodData Central: a branded label record for potato starch (USDA has no non-branded record for it) and SR Legacy records for potato flour and cornstarch.6 13 14

Per 100 g	Potato starch	Potato flour	Cornstarch
Calories	333	357	381
Carbohydrate	83.3 g	83.1 g	91.3 g
Fiber	0 g	5.9 g	0.9 g
Protein	0 g	6.9 g	0.26 g
Fat	0 g	0.34 g	0.05 g
Potassium	58 mg	1,000 mg	3 mg
Calcium	17 mg	65 mg	2 mg
Iron	0 mg	1.38 mg	0.47 mg

The table leaves out resistant starch, since the figure depends on the lab. The raw powder has tested at 50% to about 70% resistant starch, which puts a 12-gram tablespoon at about 6 to 8 grams.2 4 That share is where its value lies, because you're not buying potato starch for vitamins or minerals but for the part of each spoonful that reaches your gut bacteria as food.

Is potato starch good for you?

Quick answer

Yes, raw potato starch is good for your gut. It's a resistant starch that feeds your gut bacteria, with human trials behind it for butyrate, regularity and blood sugar. Cooked, it's a refined starch, a handy gluten-free thickener in small amounts.4 5 1 8

Food works as medicine when it gives your body what it's missing, and what a low-fiber diet leaves out is food for your gut bacteria. Raw potato starch supplies it in a spoonful, stirred into cold water or unheated food, just as the trials gave it.4 1

Heat it, though, and potato starch becomes a different ingredient, one that digests like any refined starch and brings no fiber or protein and only traces of minerals.8 6 So it belongs in your kitchen by the spoonful, in a pot of soup or a pie filling, rather than as a staple of your diet, and the same goes for packaged foods that list it. When a listener told me she'd gone gluten-free, my advice was to skip the packaged gluten-free foods and eat real, unprocessed food.15

Raw (unmodified) potato starch vs. cooked: why heat matters

Quick answer

Raw, unmodified potato starch is half or more resistant starch; cooking turns it into ordinary, digestible starch. Heated in liquid, its granules swell into a gel that's easy to digest. For the gut benefit, stir the raw powder into something cold.8 16

Heat is what turns potato starch from gut food into a thickener. Warm it in water and the tight granules swell and gel, the same change that thickens a gravy, and that gelled starch is highly digestible, so your own enzymes break it down instead.8 In a test-meal study in which 10 young men each tried both, the raw potato starch was 54% resistant starch, while the precooked starch had none.16 That's why the trials had people mix the powder into cold water or unheated food and told them never to add it to anything warm,4 1 so keep your spoonful out of your morning coffee.

Cooked starch can win some of that resistance back, which is good news if you love potatoes. When cooked potatoes cool, their starch chains pack together again into a new resistant form, called retrograded starch.8 That's the whole-food route I teach for potatoes:

Cook your potatoes, let them cool, and eat them later that day or the next day. The type of starch in sweet potatoes, white potatoes, purple sweet potatoes, any type of potato, is fantastic. This type of resistant starch is the number one starch that's going to support butyrate production.Dr. Josh Axe, DC, DNM, CNSFrom The Shocking Reason Your Anxiety, Brain Fog & Bloating May Start in Your Gut, The Dr. Josh Axe Show (2026), at 38:50

I also believe plantains have a similar type of starch in them.10 Chilled potatoes go easier on your blood sugar, too, in two trials a potato industry group funded. In the first, 30 women with high fasting blood sugar and insulin each tried both, and a baked russet potato eaten chilled left insulin 25.8% lower at 15 minutes than the same amount of boiled potato. Blood sugar ran 4.8% and 9.2% lower at 15 and 30 minutes, though blood sugar over the whole test didn't differ.17 In the second trial, a pilot study of 19 adults who each tried both, about two cooked-and-cooled potatoes spread across a day lowered the next morning's fasting blood sugar compared with matched starchy foods, while insulin sensitivity didn't change.18

Raw potato starch and cooked-and-cooled potatoes are two routes to the same goal: more resistant starch reaching the bacteria in your colon, and you can use both.

How potato starch works in your body

Raw potato starch works by feeding your gut bacteria, and the ones that make butyrate turn it into fuel for your colon lining.10 3 A spoonful takes this path from your glass to your colon:

1It resists your digestive enzymes.

Raw potato starch is packed in tight granules that the enzymes in your small intestine can barely break down, so half or more of it passes through undigested.1 2

2It reaches your colon intact.

There, starch specialists such as Bifidobacterium adolescentis and Ruminococcus bromii break the granules open.2 4

3Your bacteria turn it into butyrate.

Then the butyrate makers take up the pieces and turn them into short-chain fatty acids, including butyrate.2 4

4Butyrate fuels your colon lining.

In colon cells taken from surgery, burning butyrate accounted for 73% to 75% of the oxygen the cells used when it was their only fuel.3

5A better-fed gut lining.

Butyrate and the other short-chain fatty acids power your cells, help seal your gut barrier and calm inflammation.10

Here's how I've summed up why that matters for you:

Short-chain fatty acids are fuel for your colon and for your cells, and they calm inflammation. They power your cells and seal your gut barriers.Dr. Josh Axe, DC, DNM, CNSFrom The Shocking Reason Your Anxiety, Brain Fog & Bloating May Start in Your Gut, The Dr. Josh Axe Show (2026), at 13:41

Potato starch benefits

Raw potato starch's benefits start in your gut and reach all the way to your blood sugar. Each card's badge shows the kind of evidence behind it, from human trials to traditional use, so you can see at a glance how solid each one is.

Feeds the bacteria that make butyrate

Moderate evidenceHuman studyRandomized controlled study of 174 young adults in four groups, 2 weeks (43 on potato starch); study of 20 young adults with no comparison group; placebo-controlled trial of 84 adults, 12 weeks

Raw potato starch raised butyrate more than inulin or corn starch did. In a randomized study, 174 healthy young adults were split into four groups for 2 weeks, and the 43 who took 40 to 48 grams of raw potato starch a day in cold water raised their stool butyrate 29%, from 13 to 16 mmol/kg. That was the only significant change in butyrate among the groups. The groups taking 20 grams of inulin (up 17%), a digestible corn starch (up 13%) or 40 to 48 grams of high-amylose corn starch (up 5%) didn't change significantly.

Responses varied from person to person, and butyrate rose in 63% of the potato starch group. People who already carried the starch-loving microbe Ruminococcus bromii were about twice as likely to respond, 22 of 29 against 5 of 14,4 so the bacteria you already carry can shape how you respond.

Butyrate also rose in a study of 20 students with no comparison group, from 8 to 12 mmol/kg on average, and from 9 to 15 in the 11 who responded best.2 And over 12 weeks, in a placebo-controlled trial of 84 adults, 30 grams a day raised Bifidobacterium, one of the main beneficial gut bacteria, in both older and middle-aged adults.19

Raw potato starch raised stool butyrate the most

Source: Baxter et al. · mBio, 2019 (Table 1) [4]Average change in stool butyrate after 2 weeks; only the raw potato starch group's rise was statistically significant. 43 people took potato starch.

Fewer hard, lumpy stools

Emerging evidenceHuman studyPlacebo-controlled trial of 75 adults, 3.5 g or 7 g a day for 4 weeks

About a teaspoon a day was enough to change stool form. In a 4-week trial of 75 healthy adults funded by the maker, people got 3.5 grams of raw potato starch a day, 7 grams, or a digestible corn starch placebo, and neither the people nor the researchers knew who got which. Looking at the last 7 bowel movements each person logged, 168 in each group, the researchers found that on 3.5 grams, 9 were hard or lumpy, against 23 on placebo, fewer than half as many, and none were watery, against 6 on placebo. Bifidobacterium and Akkermansia also rose more than on placebo once a few outlying results were set aside.5 A follow-up analysis found average bowel-symptom scores, low in these healthy volunteers to start with, didn't change in any group.20 The 7-gram dose did no better than 3.5 grams, which is one more reason to start with a teaspoon.5

Fewer hard, lumpy stools on 3.5 grams a day

Source: Bush et al. · Nutrients, 2023 (Table 4) [5]Hard or lumpy stools are types 1 and 2 on the Bristol Stool Chart. Neither the people nor the researchers knew who got what.

Steadier blood sugar

Emerging evidenceHuman studyPlacebo-controlled trial of 84 adults, 30 g a day for 12 weeks (the drop was in the 42 over 70); test meals in 10 men who each tried both

Raw potato starch brought fasting blood sugar down in older adults. In a placebo-controlled trial, 30 grams a day for 12 weeks lowered it from 5.8 to 5.5 mmol/L in adults over 70, while the placebo group stayed at 5.8.1 (The blood sugar section below has the details.) In the test-meal study, raw potato starch also raised blood sugar and insulin less than a precooked starch at a single meal.16

Gut balance and inflammation support

PreclinicalAnimal studyRats on a high-fat diet with 12% potato resistant starch; mice fed four raw starches for 16 weeks

Potato resistant starch kept gut bacteria in balance and lowered inflammation in rats and mice. In rats on a high-fat diet, adding potato resistant starch prevented the shift toward unhealthy gut bacteria and lowered inflammation throughout the body. It also improved blood sugar control and kept the gut's fullness signals to the brain working, so the rats ate less.21 In mice fed raw corn, wheat, rice or potato starch for 16 weeks, the potato starch group gained the least weight and fat and had the best insulin sensitivity, along with the biggest rise in Akkermansia.22

Gluten-free thickening

Traditional useTraditional useGenerations of kitchen use; a side-by-side test-kitchen comparison with cornstarch

Potato starch is naturally gluten-free, and cooks have long reached for it to thicken gravies, soups and fruit fillings, and for gluten-free and Passover baking. It thickens at a lower heat and to a greater degree than cornstarch, so a little goes a long way in your pot (the comparison with cornstarch below has the ratio).9

Can potato starch help your blood sugar?

Quick answer

It can, mostly through your gut. In a placebo-controlled trial, 30 grams of raw potato starch a day for 12 weeks lowered fasting blood sugar in adults over 70.1

How could a starch that feeds bacteria in your colon change your blood sugar? One of the ways I tell people to boost GLP-1 naturally is more soluble fiber and resistant starch. They act as prebiotics, and the short-chain fatty acids your gut makes from them, butyrate among them, directly stimulate GLP-1.23

If you're older, the details of that trial are worth a closer look. In the placebo-controlled trial of 84 adults, funded in part by the maker, everyone took a placebo for the first 2 weeks, and then about half switched to 30 grams of raw potato starch a day in an unheated drink or food. Among the 42 adults over 70, fasting blood sugar in the 22 on potato starch fell from a median of 5.8 to 5.5 mmol/L (about 104 to 99 mg/dL), while the 20 on placebo stayed at 5.8. In the 42 adults aged 30 to 50, whose blood sugar started lower, nothing changed significantly.1

Fasting blood sugar fell in adults over 70

Source: Alfa et al. · Frontiers in Medicine, 2018 (Table 3) [1]Median fasting blood sugar, about 104 to 99 mg/dL.

Raw starch is easier on your blood sugar at a meal, too. In the test-meal study, where each man tried both, a sweetened drink made with 50 grams of raw potato starch raised their blood sugar and insulin less than the same amount of a precooked starch,16 which makes sense, since more than half of that raw starch was resistant.

If you're already living with type 2 diabetes or prediabetes, pooled trials of this raw-granule type of resistant starch, called RS2, have found blood sugar benefits for people like you. A review of 36 trials of different resistant starches in those groups found that the RS2 type lowered blood sugar after meals and, in the longer trials, fasting blood sugar and insulin too.24 A second review cast a wider net, with 22 trials in a broader mix of people, 20 of them using high-amylose corn starch. It found lower triglycerides in healthy people, by about 9 mg/dL, and a small drop in body weight in people with type 2 diabetes, about 3 pounds, but no change in fasting blood sugar or HbA1c.25

Potato starch works best as one piece of a plan. In my Insulin Resistance & Prediabetes Protocol, the first moves are cutting sweet drinks and refined carbs, eating vegetables and protein before carbs, and walking 10 to 15 minutes after your two biggest meals, followed by strength training three times a week.26 A spoonful of raw potato starch fits right alongside those steps.

Two markers that show how your body handles sugar

Fasting blood sugar is only part of the picture. These two show it more clearly:

Fasting insulin: How hard your body works to keep blood sugar steady. The optimal range is 2 to 8 µIU/mL.
HbA1c: Your average blood sugar over about three months. The optimal range is 4.8% to 5.3%.

Have results? Analyze them free →

How to use potato starch

Quick answer

For your gut, stir raw potato starch into something cold: start with 1 teaspoon a day and build over 2 to 3 weeks toward 1 to 2 tablespoons. To cook, thicken gravies, soups and pie fillings with 2 teaspoons for every tablespoon of cornstarch.5 1 7 9

The trials used anywhere from 3.5 grams a day, about a teaspoon, to 48 grams, with the higher amounts reached gradually over days to weeks.5 4 2 It's a bit like starting at the gym, where you wouldn't load the heaviest weight on day one, and your gut bacteria need the same easy start. Here are the simplest ways to use it, raw and cooked:

In cold water or a smoothie. Shake a teaspoon into a glass of water, or blend it into a cold smoothie made with coconut milk or goat milk kefir. It has almost no flavor, so you'll barely notice it.

In yogurt. Stir it into goat or sheep yogurt or coconut yogurt with berries and seeds. Cultured A2 cow's yogurt works too, if you tolerate dairy.

In overnight oats, eaten cold. Stir it into your overnight oats after they've soaked, and eat them straight from the fridge.

To thicken gravies, soups and stews. Whisk it into a little cold broth or water first, then stir the slurry in near the end. It thickens before the pot even reaches a full simmer.9

In fruit fillings and puddings. It thickens fruit fillings the same way it thickens a sauce, at a lower heat than cornstarch.9

In gluten-free and Passover baking. Use it as one part of a gluten-free flour blend for breads and cakes.

When you shop, choose organic potato starch if you can find it. At home, keep the bag sealed in a cool, dry cupboard, and keep the raw spoonful away from heat so its resistant starch stays intact.8

Questions about potato starch?

Ask Dr. Axe AI. Answers are grounded in this library, with sources shown.

Potato starch recipes

Two of these keep the starch raw for your gut, and two use it as a thickener, including a gravy for your Thanksgiving table:

Gut-healing smoothie. Make our gut-healing smoothie with coconut milk, greens, avocado and frozen banana, and add 1 to 2 teaspoons of raw potato starch before you blend. It's served over ice, so the resistant starch stays intact.
Berry yogurt bowl. Stir 1 teaspoon of raw potato starch into a cup of goat milk yogurt or coconut yogurt, then top it with berries, chia seeds and a small drizzle of raw honey.
Thanksgiving giblet gravy. Our giblet gravy for turkey or chicken thickens with a tablespoon of arrowroot. To make it with potato starch, whisk 2 teaspoons into a little cold bone broth and stir it in during the last minutes of simmering, adding more slurry if you want it thicker.9
Coconut milk pudding. Our coconut milk pudding is thickened with arrowroot whisked into eggs. Swap in potato starch, whisked in the same way, and take the pot off the heat as soon as the pudding thickens, since potato starch sets at a lower heat.9

Potato starch vs. cornstarch

On paper, cornstarch and potato starch look almost like twins, since both are nearly pure starch, with almost no protein or fiber in either. Per 100 grams, cornstarch has 381 calories and 91.3 grams of carbohydrate, against 333 and 83.3 in potato starch.14 6 The difference shows up at your stove. When a test kitchen put the two side by side, the same amount of potato starch made a thicker sauce, and it thickened before the sauce reached a full simmer, while cornstarch needed a couple of minutes of simmering. The cooks settled on 2 teaspoons of potato starch for every tablespoon of cornstarch,9 so you use less of it and add it later.

Both are naturally gluten-free, and our guide on whether cornstarch is gluten-free covers what to look for on the label. Choose organic corn products, too: my Healing Leaky Gut Protocol switches corn, oats and soy to organic to keep glyphosate residue off your plate.27

Potato starch vs. potato flour

The names are similar, but potato flour is made from whole potatoes, dried and ground, while potato starch is only the starch, the potato's energy store, and you can see the difference on the label. Per 100 grams, potato flour carries 5.9 grams of fiber, 6.9 grams of protein and 1,000 milligrams of potassium, against none, none and 58 milligrams in potato starch.13 6 That's why they don't swap one for one, so use the one your recipe names.

Potato starch substitutes: what to use instead

Quick answer

To thicken, swap in cornstarch, arrowroot or tapioca starch. For the gut benefit, eat cooked-and-cooled potatoes or plantains, or use green banana flour.9 28 10

If you run out of potato starch with a gravy on the stove, cornstarch is the easiest swap: use 1 tablespoon of cornstarch for every 2 teaspoons of potato starch a recipe calls for.9 Arrowroot and tapioca starch are on my list of naturally gluten-free flours, along with coconut, almond, cassava and buckwheat flours, so they suit gluten-free thickening and baking.28

For the gut benefit, reach for another source of resistant starch: cooked-and-cooled potatoes and plantains, as in the raw-versus-cooked section, or try green banana flour, made from unripe bananas, whose raw starch is the same granule type as raw potato starch.25

Who should be careful with potato starch?

Quick answer

Potato starch is a safe everyday food for most people. The common side effect of the raw powder is gas or bloating at first, which is why you start small.5 1

Who needs to take care with potato starch:

Gas and bloating at first: In the 4-week placebo-controlled trial of 75 adults, the side effects that might have come from the starch were gas, bloating, belching and one case of belly pain. None of them were serious, and most turned up at 7 grams a day rather than 3.5,5 so if you feel a little gassy in the first weeks, you haven't done anything wrong. If you have bloating, IBS or food sensitivities, my advice is to start low and slow: your microbiome needs time to adapt, and a sudden jump in resistant starch can overwhelm an unbalanced gut.7 Start with 1 teaspoon a day in something cold and add a little more every few days, as long as your gut stays comfortable.
Leaky gut or a sensitive gut: If you have leaky gut, bloating or gas, raw potato fiber is very hard to digest. With those, you want gentler prebiotics, such as partially hydrolyzed guar gum (PHGG) or acacia fiber.29 Add raw potato starch once your gut has calmed down.
SIBO: In my SIBO protocol, small portions of cooked potatoes are on the friendly list, and fermentable foods come back one at a time in Phase 3, Restore.30 That's the time to try raw potato starch, starting with a teaspoon.
Potato allergy: Potato allergy is rare, and its main allergen is a potato protein called patatin.31 32 If potatoes give you hives, swelling or wheezing, skip potato starch too.
Celiac disease: Potato starch is naturally gluten-free, but naturally gluten-free flours and starches can pick up gluten on the way to you. In a Canadian survey, 61 of 640 carried more than 20 parts per million of gluten, against 3 of 268 that were labeled gluten-free.33 The label matters, so buy potato starch labeled gluten-free.

The bottom line

Should you use potato starch?

Yes, and raw is where its value lies. Raw potato starch is one of the simplest ways to feed your gut bacteria. In human trials, it raised butyrate, cut down on hard stools at about a teaspoon a day and lowered fasting blood sugar in adults over 70. Cooked, it's a gluten-free thickener that does the job with less starch than cornstarch.

So start with a teaspoon a day stirred into something cold, and build up over a few weeks. Keep eating the cooked-and-cooled potatoes, plantains and vegetables that feed your gut from the plate, too, because when those bacteria are well fed, they feed the lining of your colon in return.

Get the free Healing Leaky Gut Protocol

The 6R roadmap, the gentle prebiotics to start with while your gut heals, the foods that heal and a 7-day meal plan.

Free with your Dr. Axe account (email or Google). You'll also get the protocol's short email series and the Dr. Axe newsletter; unsubscribe anytime.

Open the free protocol →

Potato starch: frequently asked questions

Is potato starch gluten-free?

Yes. Potato starch is naturally gluten-free. With celiac disease, buy one labeled gluten-free, since naturally gluten-free starches can pick up gluten before they reach you.33

Is potato starch bad for you?

No. Raw potato starch is a prebiotic that feeds your gut bacteria, and cooked potato starch is a safe gluten-free thickener in kitchen amounts.4 9 The main side effect of the raw powder is gas or bloating at first, which is why you start with a teaspoon.5

How much potato starch should I take a day?

Start with 1 teaspoon a day, stirred into something cold, and build over 2 to 3 weeks toward 1 to 2 tablespoons. Trials used 3.5 to 48 grams a day, and 3.5 grams, about a teaspoon, was enough to change stool form in a placebo-controlled trial of 75 adults.5 4

What is modified potato starch?

Modified potato starch is potato starch that has been treated with acids, bleaching agents or other approved agents to change how it behaves in processed foods. U.S. rules call it food starch-modified.12 It's a different product from raw, unmodified potato starch, the kind used in the gut trials.1

Does potato starch help with weight loss?

Possibly. In mice fed raw potato starch for 16 weeks, the potato group gained the least weight and fat of four raw starches, though it hasn't been tested for weight loss in people.22 In a test-meal study in which 10 men each tried both, raw potato starch left them feeling less full than a precooked starch.16 Its clearest job is feeding your gut bacteria.

Is potato starch a nightshade?

Yes. It comes from potatoes, which are nightshade vegetables, and my guidance is that most people do fine with nightshades.34

Is potato starch the same as resistant starch?

Not exactly. Resistant starch is any starch that escapes digestion and feeds your gut bacteria, and raw potato starch is one of its richest sources, at 50% to about 70% resistant.2 4 Once it's cooked, potato starch loses that resistance.8

Is potato starch keto?

Not in cooking amounts. A tablespoon carries 10 grams of carbohydrate,6 and our keto diet guide keeps net carbs to about 20 to 50 grams a day.35 A raw teaspoon a day for your gut adds about 3 grams of carbohydrate, half or more of it resistant starch that escapes digestion.6 2

Is potato starch genetically modified?

Not usually. The genetically modified potato bred for its starch was grown only for industrial use and isn't fit for eating, and 45 potato-based foods tested in one survey carried none of it.36 Choose organic potato starch when you can.

Freshness & update log

October 29, 2026 — Rebuilt the page under Dr. Axe's byline, around what raw potato starch does in your gut. Added the Dr. Axe Score with its math; nutrition from USDA FoodData Central with a side-by-side table of potato starch, potato flour and cornstarch; why heat removes the resistant starch, and the cooked-and-cooled potato route; how it works in your body, with a step diagram; benefits ranked by evidence, from the human trials of raw potato starch for butyrate, stool form and fasting blood sugar, with three charts; a blood sugar section; how much to take and how to use it raw and cooked; four recipe ideas, including a Thanksgiving gravy; and one safety section. Kept from the earlier page, each now sourced: the blood sugar and gut bacteria benefits, the rat and mouse studies, its gluten-free and Passover uses, its thickening uses, the amylose and amylopectin split, the tablespoon nutrition (now from USDA), the potato flour and cornstarch comparisons, the substitutes, the digestive-upset and potato-allergy cautions, and the advice to choose organic. Corrected: the 2010 insulin-sensitivity trial the earlier page cited used a corn resistant starch, not potato starch, so it's no longer presented as a potato result; resistant starch per tablespoon is now "about 6 to 8 grams"; the cornstarch swap is now 2 teaspoons of potato starch per tablespoon, from a side-by-side test; and the Passover note now explains kitniyot. Removed, after a search turned up no support: "often genetically modified" (the one genetically modified starch potato was an industrial crop, and 45 foods tested negative), "cornstarch is a more nutrient-rich alternative" (USDA shows both near zero), the claim that resistant starch is more filling than pasta and rice, "potato starch can handle higher temperatures", the duck study, and water chestnut flour as a substitute.

References

Dr. Josh Axe, DC, DNM, CNS

Doctor of Natural Medicine · Founder, DrAxe.com

Dr. Axe is a certified doctor of natural medicine, clinical nutritionist, and multiple New York Times bestselling author. He has spent 20+ years in clinical practice helping people heal at the root cause and founded one of the most-visited natural-health platforms in the world.

Read the full bio →

This article is for educational purposes. See our medical disclaimer.

On this page

What is it?
Nutrition
Is it good for you?
Raw vs. cooked
How it works
Benefits
Blood sugar
How to use it
Recipes
Vs. cornstarch
Vs. potato flour
Substitutes
Who should be careful
The bottom line
Should you use potato starch?
FAQ

Quick facts

What it isThe starch extracted from potatoes, a fine white powder with almost no flavor
One tablespoon (12 g)40 calories and 10 g carbohydrate, with no fat, protein or sugar on the label
Resistant starchAbout 6 to 8 g per tablespoon while it's raw; cooking turns it into ordinary starch
Everyday amount (raw)1 teaspoon a day in something cold, built up over 2 to 3 weeks toward 1 to 2 tablespoons
Thickening swap2 teaspoons of potato starch for every tablespoon of cornstarch
Interaction checkLow; no meaningful drug interactions documented

Ask Dr. Axe AI

Ask a question→