Nutrition Hack: Potato Starch

Strohauer Farms’ Guide to Resistant Starch


One of the major developments in our understanding of the importance of carbohydrates for health in the past twenty years has been the discovery of resistant starch.
— Joint Food & Agricultural Org. of the United Nations / WHO, 1997; The Potato Hack, pg. 160


Many people today would attribute potatoes going straight to the gut, and ironically, they are right. While many Americans today shun the white potato in their diets, they are missing out on critical nutritional needs our guts demand: resistant starch (RS), specifically from potatoes. Mark Sisson in his Mark’s Daily Apple blog proposed, “[...] with more and more science emerging every day, it’s becoming obvious that the gut biome is the next health frontier.” Scientists, medical practitioners and nutritional thought leaders are now learning about how much of our health is affected by our gut microbes and their need to be fed prebiotics, specifically the kind derived from resistant starch.

What is Resistant Starch?

It’s a type of starch that acts more like a fiber and isn’t consumed in your small intestine, therefore, making its way intact to the large intestine. Why is this a good thing? It’s food that our gut bacteria eat. Our intestinal bacteria receive fuel from prebiotics, such as resistant starch, that produce short-chain fatty acids that allow the gut lining to remain intact and healthy. This is vital to maintaining a healthy metabolism, improving blood sugar, and promoting weight loss and many other optimal bodily functions.

RS Health Benefits

Probably the most widely studied effect of RS and one of its biggest ‘selling points’ is in its control of blood sugar.
— Tim Steele, The Potato Hack, pg. 172
The cool part about resistant starch in relation to digestible starch is that its fermentation yields butyric acid, a short chain fat that actively improves insulin sensitivity and blood glucose control. In other words, it helps you become more tolerant of the carbs you can digest.
— Mark Sisson, Mark’s Daily Apple blog


The Potato Hack by Tim Steele is considered to be one of the most in-depth research resources on the benefits and importance of resistance starch in the human diet. Below are included a few excerpts from his book on the health benefits derived from RS, as well as how RS is showing to affect cancer and weight loss.

Studied effects of RS to (The Potato Hack, pg. 171):

-       Improve bowel health

-       Lower pH

-       Increase epitheleal thickness

-       Kill cancer cells

-       Lower postprandial glycemia

-       Increase insulin sensitivity

-       Reduce body weight and prevent weight regain

-       Decrease inflammation in the intestines and entire body

-       Reduce the risk of breast cancer and colorectal cancer

-       Reduce cholesterol/triglycerides

-       Increase production of brain neurotransmitters serotonin and melatonin

-       Remove certain pathogens from small intestine

-       Preserve Vitamin D in the body

-       Increase mineral and vitamin production and uptake

-       Remove toxins and heavy metals from the bloodstream

-       Increase satiety and regulate hunger hormones

-       Reduce fat storage after meals

-       Improve gut microbiome (synergy, prebiotic, symbiotic)

-       Protect probiotic bacteria

RS & Cancer

“Due to its ‘resistant’ nature, RS is being used in chemotherapy to protect cancer drugs from digestive processes and to target colon cancer cells. When drugs are coated with a RS layer of a particular thickness, a precise targeting method is produced with profound impact on the treatment of bowel cancer. And lastly, breast cancer is seeing the benefits of RS therapy. Breast cancer is a huge concern for women on estrogen therapy - recent mouse studies have shown a decrease in breast cancer cells and improvements to how their bodies metabolized circulating estrogen. To get the benefits of RS for breast and other cancers, one simply has to eat RS rich foods.”

“Nearly all of the studies done on RS in the last 3 years have been centered around cancer prevention and cures - and not just colorectal cancer, but also breast cancer and the use of RS as a chemotherapy enhancer. RS has been shown to reduce the survival of human colon cancer cells through its stimulation of short-chain fatty acids. When cancer cells are exposed to high doses of RS boosted butyrate, they are killed through DNA fragmentation, also known as cell apoptosis. A diet high in RS has been shown to prevent the formation of cancer cells altogether.”

~ Tim Steele, The Potato Hack, pg. 175

RS & Weight Loss

“What is very apparent in the studies of RS and weight is that when gut bugs are fed RS, they will do everything in their power to help get you to a lean, healthy state. Studies that look simply at weight often fail to see reductions because RS can actually lead to a heavier, thicker, healthier intestinal tract and increase the numbers of bacteria living there - a weight gain everyone should be happy with. Another interesting field of research into RS has to do with regaining weight lost through exercise; it was found that after losing a considerable bit of fat, keeping it off was easier with RS than with continued exercise - and certainly intestinal microbe driven through better hunger signals and fat storage hormones. What is really exciting is that the addition of RS, post weight loss, clearly showed a trend toward muscle growth and away from fat storage - the main goals for improving insulin sensitivity.”

“You may have heard of ‘cortisol,’ a stress hormone that often stymies weight loss and muscle building progress. Well, cortisol is no match for RS … cortisol is lowered on an RS supplemented diet and helps explain the reduction in weight regain and also has been implicated in whole-body energy metabolism. The cortisol connection is entirely driven by gut bugs and is probably one of their most important contributions to our overall health.”

~ Tim Steele, The Potato Hack, pg. 173

Potato Starch as a RS Source

Why use potato starch? It’s a safe, concentrated form of resistant starch, it’s inexpensive and it can be easily found in any local grocery store. Potato starch is generally well-tolerated, even by people who experience nightshade allergies. In The Bulletproof Diet, Dave Asprey adds, “Another benefit of resistant starch is that when taken at night, it can stabilize blood sugar and provide building blocks for serotonin, helping you sleep better,” (pg. 52). This effect is also supported and promoted by Dr. Mark Hyman.

How much RS should be included in your diet?

It’s recommended to try and get in anywhere from 30-40 grams per day. Below shows you how much potato starch is needed to reach this goal from different potato starch sources:

-       1 Tbs. of potato starch = 9 grams of RS

-       1 medium raw potato = 22 grams of RS

-       1 medium potato cooked & cooled = 3.5 grams of RS

-       1 medium potato cooked & cooled, then reheated = 4 grams of RS

RS vs. Fiber

Often people wonder what the difference is between RS and fiber. Below are a couple, quick excerpts from The Potato Hack on their differences. We are beginning to see the effects of misguided information on increasing fiber rather than focusing on increasing resistant starch in our diets. As more research and information is presented on these differences, we will update this section of our RS guide.

The 15-20 grams of dietary fiber that most people consume daily doesn’t even account for 25% of the butyrate producing fiber we need, however, adding 20-40 grams of RS would bridge this gap nicely.
— Tim Steele, The Potato Hack, pg. 181
Rural Native Africans eating a very basic diet high in resistant starch and low in dietary fiber have a colorectal cancer rate of less than 1 in 10,000. Australians eating a diet low in RS and high in dietary fiber have a colorectal cancer rate of 1 in 12.
— Tim Steele, The Potato Hack, pg. 178


Net Effect of RS

Many people today follow some form of a lower carbohydrate or cyclical carbohydrate diet. It’s important to realize that RS is not digested as a carbohydrate but rather a fat. Our healthy gut bugs are the beneficiaries of these calories and convert them to short-chain fatty acids. Therefore, 4 Tbs. of potato starch = approximately 54 calories from fat.  

How to Feed a Healthy Gut

Let’s make this practical. Below are some ways to not only incorporate potato starch in your diet but also other forms of RS.

Increase your RS3 consumption by cooking, cooling & then reheating your potatoes, rice or beans. Foods with the highest levels of RS are raw potatoes, green bananas, plantains, cooked & cooled potatoes, cooked & cooled rice, parboiled rice and cooked & cooled legumes. Grocery store sushi that’s been cooling in the refrigerator will also have a good amount of RS. (A fun sushi tip from Bulletproof Diet founder, Dave Asprey, is to drizzle MCT oil over sushi to provide a barrier against quick digestion for an added bonus!) Another way to increase your levels of RS3 is to cook your potatoes ‘al dente. This means you slightly undercook them which retains more of their resistant starch. Dr. Oz is a big proponent of this way of potato preparation. Potatoes will be slightly undercooked if they are slightly crunchy and there’s some resistance when you try to take a knife through them. Keep in mind, sweet potatoes have almost no RS.

Increase your RS2 consumption by mixing 1-4 Tbs. raw unmodified potato starch (not flour and must be unmodified) into either a cold glass of water, mineral water like Pellegrino, probiotic liquids such as Kombucha, milk (almond, coconut, cow, goat, etc.) or in your yogurt. By mixing potato starch in your yogurt or probiotic liquids, it’s increasing the absorption rate of the probiotics by helping them bypass the small intestine and having a better chance of reaching the large intestine intact. Try Bob’s Red Mill Unmodified Potato Starch. You can also try mixing in a green banana with your smoothie. One large, green and unripe banana will contain about 20-25 grams of RS. Other good sources that can be used are plantain flour, green banana flour and tapioca starch.

Supplement your RS with probiotics. This is especially important if you experience negative side effects with RS. That is a strong indicator your gut is not healthy, and probiotics will help you. Primal Defense Ultra, AOR Probiotic-3 and Prescript Assist are the most highly recommended supplements from thought leaders in the resistant starch arena, such as Tim Steele, Richard Nikoley and Dave Asprey.

Eat inulin containing vegetables, not to be confused with insulin, such as Jerusalem artichokes and psyllium. These prebiotic-rich foods are also great sources of resistant starch. One of today’s leading Ketogenic diet and its effects’ researchers, Dominic D’Agostino, and Primal lifestyle founder, Mark Sisson, both include Jerusalem artichokes in their diets.

Include healthy fats, such as coconut oil, when cooking rice or potatoes. When these are cooked together, the oil from the healthy fat binds to the digestible starch. The digestible starch is the typical starch in our diets that is converted into glucose, not RS. With the binding of the oil, the digestible starch begins to crystalize, thus creating RS. Also cooling the starch with the healthy fat included allows the crystallization process to occur. One study found this increased the amount of RS by 10-15 times![1]

Incorporate refeed days. For those who eat similar versions of either a Ketogenic, Cyclical Ketogenic, Anabolic, Bulletproof, Paleo, Atkins or Modified Atkins diet, carbohydrates are consumed in smaller and fewer amounts, so it’s harder to get in the daily requirements of RS. Although RS can be counted as grams of fat rather than carbohydrates, unless you’re only eating a concentrated form of starch (such as potato starch), other sources will still contain starches that are quickly digested in the small intestine and converted into glucose. “Refeed days” are promoted by most of the above listed diets, where 1-2 days per week the amount of carbohydrates consumed is increased. This is a great opportunity to incorporate RS3 in the form of cooled potatoes or rice. Ideally, eat RS-rich foods on days you work out, especially after a glucose depletion day such as heavy lifting or a HIIT workout. Your liver and muscle glycogen storages will be depleted, so instead of storing the ingested carbs in the bodies’ fat cells, they will immediately be shuttled to those depleted reserves.

Keep your gut guessing. Feed it like it would be fed in an unprocessed world. Vary the doses or amounts you consume of RS each day. Sometimes skip days where you don’t consume RS. Incorporate various forms. Make sure you’re getting both RS2 and RS3, as different bacteria in our guts want each of these. As we hear in the nutrition world all the time, keep your body guessing.

Finally, get your hands in the dirt! Soil contains a healthy dose of probiotics. Here at the farm, we don’t have too much trouble with this tip. Consider growing a garden or planting flowers.

If you’re looking to optimize your health, increase weight loss, improve your metabolism or any of the other health benefits previously described, resistant starch is a great nutrient source to consider including in your diet. Potato starch is not only one of the most readily RS sources available, but the humble potato has all the nutrients a person needs to survive. It’s a powerhouse vegetable, and it’s the most recommended source for resistant starch. Give it a try, and let us know what you think in the comments below.

As the 4th of July is approaching, here’s a great recipe for a Resistant Starch Potato Salad from Mark’s Daily Apple blog:

Servings: 4 to 6

Prep Time: 20 minutes + 8 hours inactive

Cook Time: 30 minutes


  • sea salt & pepper
  • 8 medium potatoes
  • 1/4 to 1/3 cup mayo (Primal Kitchen Mayo recommended)
  • 2 Tbs. mustard
  • 1 bunch green onions
  • 4 boiled eggs


Peel the potatoes if desired. Cut into bite-sized pieces. Boil them with a few pinches of salt until barely cooked and then drain. Set potatoes aside until cool. Place them in a bowl, cover and chill overnight (must do this step for RS to occur).

In the morning, add the salt & pepper liberal with the mayo and mustard. Slice the green onions and chop the eggs and add them. Mix everything together and adjust seasonings to taste. 

Serve & enjoy! 


Great RS Resources:

-       The Potato Hack by Tim Steele

-       The Bulletproof Diet by Dave Asprey

-       Eat Fat, Get Thin by Dr. Mark Hyman

-       Article, Blog & Video Links