Resistant Starch Basics: The Health Benefits of Eating Raw Potatoes

Resistant starch” is a relatively new phrase to many of my readers, and I seem to be finding more and more articles on the subject. However, like chasing a fleeting butterfly, it’s difficult to find enough time to study the connections between prebiotic fibers and foods that contain resistant starch. And when that issue is finally resolved, it means we need to learn about those special foods that contain resistant starch, and, last but not least, find recipes for them that would give us a head start. Whew!

What frequently happens is that many of us just skip it all and consequently miss out on the enormous health benefits of resistant starch. That’s especially true for those of us who don’t make our own probiotics! (I’ll say more about probiotics later.)

For this reason I’ll simply look at resistant starch with an eye to the essential facts. I’ll then take an ingredient that contains premium resistant starch—in this case raw and cooked then cooled potatoes. As we know potatoes are one of the most popular foods in the world—consequently, I am anxious to explain to my readers how they can make this food even more nutritional than it already is.

Resistant Starch Basics

To give us extra space to talk about potatoes, I will briefly talk about fiber in simple terms before moving on to the resistant starch issue. An interesting thing about the current popularity of resistant starch is that at one time it wasn’t even on the radar in Western and ancient cultures! There was no need to be aware that something called “resistant starch” even existed. Why? Well, the main reason is that constipation and other gastrointestinal problems used to be low or nonexistent.
There were two main reasons for this: 1) Grains, beans, legumes, vegetables, and fruits were grown without pesticides and/or chemical fertilizers; 2) After crops were harvested, they weren’t stripped of their precious fiber! Yes, when we talk about resistant starch, we’re actually talking about foods that contain a certain type of prebiotic fiber. So let’s discover its secret.

The small intestine does not digest fiber. All fiber is channeled to the colon unchanged. Most foods contain both insoluble and soluble fiber. However, some foods have more or less of either of these two fibers. Insoluble fiber contains lots of water and produces larger, softer stools. Soluble fiber is broken down when it’s fermented by colon bacteria.

Many complex carbohydrates contain starches, which are defined as long chains of glucose found in grains, potatoes, and other foods. Not all of the starch we eat gets digested, and because it resists digestion, it’s called resistant starch. What a novel idea. (Smile)

What most people may not understand when they read articles on resistant starch is that certain starchy foods contain an additional prebiotic soluble fiber called inulin, which includes its subgroup oligofructose (also sometimes called fructooligosaccharide, or FOS).

So What Is Inulin and Why Do We Need It?

Inulin is a prebiotic fiber that the body uses to create a probiotic effect in the colon. Since probiotics ultimately provide maximum colon health, we might ask why bother with prebiotics rather than just go straight to probiotics?

The simple answer is that even after all we’ve learned about the vital importance of making our own probiotics, we still don’t take the time to do so. That being the case, it’s essential that we eat a good deal of prebiotic fiber so it can convert into probiotics in our colon. Better yet is to combine both probiotics and prebiotics in our diet. See the following excerpt from “The Tremendous Benefits of Lacto Fermented Foods,” my blog post on probiotics (also know as fermented foods):

 The Tremendous Benefits of Lacto Fermented Foods

 Wonder foods that are fermented (not pickled in vinegar) may help protect against infections and fungi. Fermented foods and beverages also provide fiber, which aids digestion and could help prevent serious digestive disorders that may be the root cause of many illnesses. As described in Making Sauerkraut and Pickled Vegetables at Home by Klaus Kaufmann and Annelies Schoneck, the benefits of lactic acid are numerous. Here are just a few:

  • Prevents decay, not only in food but in the bowels.

  • Stimulates the peristaltic movement of the intestines.

  • Assists in the circulation of the blood.

  • Has a harmonizing effect on the stomach, strengthens the acidity of the gastric juice when production lags, and reduces acidity when production is up.

  • Relieves the burden on the digestive system by significantly improving intestinal digestion.

  • Increases nutrient absorption.

Potatoes: An Excellent Source of Resistant Starch

I would like to take this opportunity to share three interesting quotes from Dr. Royal Lee, one of the most prominent holistic practitioners of the twentieth century. Long before our current love affair with resistant starch, Dr. Lee showed that he was way ahead of his time in the following passage from his 1958 article “The Use of Raw Potatoes.” (The full article is available for free at the SRP Historical Archives.)

 Good for Overweight
“‘Eat potatoes instead of bread’ is good advice for the overweight who are constantly engaged in the battle of the calories. Pound for pound, potatoes furnish about one-third less calories than bread—so we may eat three times as much on a caloric basis. (There are about 100 calories per medium-sized raw potato, which is much less than a serving of spaghetti, pie or cake.) In addition, its superior digestibility and food value as a source of protein, vitamins and minerals make it ideal for reducing the caloric intake without sacrifice of many essential food factors.”

Copeland said, ‘To eat is human; to digest divine.’ While the quality of potatoes is greatly modified by the conditions and soil under which they are grown, an analysis generally shows about 75 percent water, 15 percent starch, one to two percent protein and two to three percent mineral salts. However, the nutritive value cannot be obtained on the basis of analysis alone. It is necessary to know the extent to which the various constituents are digestible. Reports show 95 percent of calories are digested, 70 to 85 percent of nitrogenous material is absorbed (40 to 60 percent is in the form of protein), and 97 percent of the iron is present in ‘available’ form (McCance and Widdowson, 1942). Potatoes have very little fat or sugar and are high in potassium, phosphorus and calcium. The richer they are in protein, the more waxy they are; and the higher they are in starch, the more mealiness they have when cooked.”

 Enzymes Destroyed
The cooked potato contains no enzymes, as all enzymes are destroyed by heat. There is an enzyme in raw milk which prevents constipation, and an enzyme in raw potatoes which does the same thing, according to clinical reports. Certainly a piece of raw potato before retiring can do no harm, and it has produced beneficial results in cases of chronic constipation. The farmer who reduces his potato intake when he comes to the city may notice that his head ‘pounds’ after meals. Quite possible this is due to a reduction in his ordinary intake of potassium—the mineral which promotes normal heart rhythm. One of the enzymes found in raw potatoes is phosphatase, which promotes assimilation of calcium and iron in particular; another is tyrosinase, an essential component of the vitamin C complex and associated directly with the function of the adrenal glands.”

More On Eating Raw Potatoes

Possibly the best and most current information I found was in my interview with Tim Steele, author of The Potato Hack. His book is primarily dedicated to the tremendous benefits of eating raw potatoes, especially to lose weight. But he also covers the many other benefits and uses of resistant starch. In my humble opinion, this is a book everyone should read and give as gift to those they love.

On page 171, Steele references no less than 19 phenomenal benefits of resistant starch, including its efficacy with treating of breast cancer, colorectal cancer, removal of certain pathogens from the small intestine, to name just a few! Visit him at his website, The Potato Hack Chronicle.

What Steele Says About the Two Types of Resistant Starch

RS2: There are basically three foods that provide the highest amounts of resistant starch (RS): 1) Raw potato or raw unmodified potato starch (Anthony’s Organic Potato Starch); 2) Green bananas, fresh or green banana powder (Zuvvi Banana Flour); 3) High-maize corn starch (King Arther Hi-Maize Natural Fiber).

Naturally, Steele is partial to the raw potato, as was Dr. Royal Lee. He advised me to inform my readers of the following: when trying to get RS for health benefits, eating most RS-containing foods (beans, wheat, oats, nuts, etc..) foods will get you 1–2g per serving. A small raw potato contains 20g or more, while a green banana contains 15g or more. Steele recommends that we get at least 30–40g per day.

Recommendations for Using Powders: “As for recommendations on amount, I always tell people to try to ingest a spoonful or two daily, or a couple times a week, as it fits their schedule. And I always tell them to start slowly. Maybe a teaspoon at first for a week or two, then a tablespoon. There is no unsafe upper limit, but most studies use 40g as their dosage when studying RS effects. A person’s normal diet hopefully provides 15–30g of other fibers and RS, so adding 10–20g (a couple spoonfuls) helps immensely to bolster daily fiber intake. If a person says, ‘But I already eat 40–50g of fiber daily, do I need potato starch?’ The answer is no, they do not need it. This is for the person who typically eats very little fiber.” (As quoted from one of my emails with Tim Steele)

RS3: This type of resistant starch comes from foods that have been cooked and then cooled down. Simply put, RS2 is found only in raw, uncooked foods. RS2 converts to RS3 when heated and then cooled. This is called “retrogradation” or “staling.” Stale bread is stale because the starches have retrograded, turning the RS2 in wheat into RS3. As long as the cooked foods are not heated above 160°F, the RS2 remains no matter what you do to it (grind, soak, freeze, etc.).

Personal note: For most of us, starting out with small amounts of resistant starch and building up would be preferable, as we simply don’t realize that our colon may be substantially compromised and in need a good cleansing due to a lack of inulin and/or other types of fiber. Since RS ferments in the colon, it could initially cause bloating and nausea. Many of us have avoided high-fiber complex carbs for so long that we have the typical symptoms of constipation and other gut issues that don’t seem to heal. Meanwhile, we don’t understand the high cost of not consuming those precious high-fiber complex carbs has on our body and our gut health over the long-term!

Important: Please be advised that I don’t endorse any supplements advertised on the websites I otherwise recommend. My preferred supplements are from Standard Process.

So Where to Get Great Potatoes?

I wouldn’t have found Tim Steele and his book had I not first discovered the loveliest potatoes from Strohauer Farms, which I recently picked up from Whole Foods. They were totally organic, and the quality was superb. After looking at the package, I was pleasantly surprised to learn that Strohauer Farms is in Lasalle, CO, right next door to where I live. Be sure to read this blog post that Strohauer Farms did on Tim’s book. Also  consider supporting this great farm and enjoying their best of the best organic potatoes. They’re a great way to get organic, raw resistant starch!

Should We Be Afraid of Eating Raw Potatoes?

You can find many articles and opinions about including potatoes, both raw and cooked, in your diet that may be meant to scare you into avoiding one of the most profound nutritional foods available. However, potatoes—whether they’re raw or cooked and then cooled—prove to be a low calorie bonanza for good health.

Testimonials from people who have survived on nothing but potatoes for months are an astonishing indication of their nutrient dense qualities. Though most of us would agree that this isn’t a sustainable diet, it’s nevertheless indisputable proof of the nutritional value of potatoes. Please take time to do a short search of this subject, and be not afraid.

Following is a commentary from Tim Steele, author of The Potato Hack:

“Hemagglutinin is just another word for lectin. Lectins are a normal anti-nutrient to help protect the potato in its growth cycle. One would possibly have to eat something like fifty pounds of raw potatoes to get a lethal dose of lectins. A small raw potato daily or every now and then has a very small amount of lectins/hemagglutinin. Additionally, raw potatoes have a high quality resistant starch, which is a highly beneficial prebiotic that helps to foster an extremely diverse gut flora. Cooked potatoes are very low in resistant starch, a key prebiotic (inulin) to help maintain superior gut health. That is not the case with a small raw potato, which is very high in resistant starch.

“The lectins are concentrated in the leaves and stems, which are not consumed. Lectins are also in green spots or greenish tinted color visible on the potato skin. These green spots are called solanine, and [they indicate] the potato should not be eaten. Lectins are also concentrated when fried, so French fries and potato chips contain the highest levels of lectins found in potato products.”

“If you look at the effects of concentrated plant defenses, we’d never eat another plant, yet these plants have a long history of being nutritious and health-promoting when eaten.

“It always amazes me how scared people have become of potatoes! We’ve been eating them for thousands of years (including raw potatoes). There have been very, very few cases of potato poisoning in the past hundred years. Bottom line: Avoid green potatoes, but otherwise, no worries!

Please readKiller Tomatoes and Poisonous Potatoes?” from Science Based Medicine.

Tim Steele, author of The Potato Hack, retired from the United States Air Force in 2004, after 21 years of service. He has a master’s degree in biotechnology from the University of Maryland University College (UMUC). Tim’s professional work includes “Hybridomas: ageing technology holds promise for future drug discoveries,” Generics and Biosimilars Initiative Journal, Volume 5, Issue 1, 2016. Tim also hosts the popular health blog The Potato Hack Chronicle, where he explores the wonders of a healthy diet.

Raw Potato Recipes: Rich in Resistant Starch

 Raw Potato Salad
—I love “easy,” and this short recipe is my idea of healthy and easy! This recipe (and other future recipes) come to you adapted and/or inspired with permissions from Hallelujah Diet (
This is my version of raw potato salad inspired by

1–2 medium, organic red or white potatoes, peels left on, washed and quartered lengthwise
1 teaspoon celery seed
2–3 small sour pickles, chopped
1 medium, organic white, yellow, or red onion, thinly sliced
Homemade mayonnaise (see Nourishing Traditions, p. 137) to taste (enough to cover ingredients)
Celtic salt, to taste
Paprika, turmeric, or dry mustard, to taste


  1. Using a fine slicer or food processor, thinly slice potatoes or chop them into bite-sized pieces. Place in a dish of cold water to prevent oxidation while preparing the remaining ingredients. When ready to add the additional ingredients, drain and pat dry with a paper towel.
  2. Add celery seed, sour pickles, and onion.
  3. Add mayonnaise and Celtic salt to taste. Marinate overnight in refrigerator.
  4. Before serving, sprinkle the top with paprika, turmeric, or dry mustard.

 Raw Potato Juice
—Here’s my own version of potato juice, which I drink either by itself or combined with some juiced organic cucumber (with peel left on). Great before breakfast or even before bed for a peaceful night’s sleep!
Caution: Don’t make this potato juice with a regular juicer. The fiber in vegetables, or in this case the potato starch, is stripped off with a juicer. Use a Vitamix or a blender to be sure the potato starch remains intact.


2 small, organic potatoes, peels left on
½ cup or more spring water (if you want it thinner)
½ organic cucumber, peel left on (optional)
1 teaspoon fresh organic lemon juice


Place all ingredients in a in Vitamix or other blender and enjoy. (Be sure to rinse your mouth after drinking to prevent your teeth from having too much contact with the lemon juice.)

More interesting facts about potato juice from “How to Juice a Potato and Why You Should Do This” at

“Potato Juice is an excellent anti-inflammatory agent that works well for arthritis, joint pain as well as back pain. Drink it in the morning on an empty stomach for best results.”

“Potato Juice is very alkaline and works to alkalize the body, thus preventing diseases such as cardiovascular disease and even cancer. Drink 1–2 glasses of potato juice every day to cure gastric ulcer, kidney disease, heart disease, diabetes, hypertension, liver disease and sore shoulders.”

 More Recipes and Miscellaneous Links

Afterthoughts from the Traditional Cook
Potatoes, potatoes! They grow in the ground,
When you dig them up they’re muddy, brown and round,
Potatoes, potatoes! Delicious mashed,
But they don’t taste so good if they’ve been bashed,
Potatoes, potatoes! Steamy in their jacket,
Potatoes, potatoes! Fresh in their packet,
Potatoes, potatoes! Can be made into chips,
Potatoes, potatoes! Are best when they’re crisps!
—“Potatoes” by Matthew Randell, May 2015

Images from iStock/robynmac (main image), margouillatphotos (multicolored potatoes), Wiktory (potato salad).  

Note from Maria: I am a Certified Natural Health Professional, CNHP, not a medical doctor. I do not diagnose, prescribe for, treat, or claim to prevent, mitigate, or cure any human diseases. Please see your medical doctor prior to following any recommendations I make in my blogs or on my website.

Maria Atwood, CNHP

Maria Atwood is a semiretired Certified Natural Health Professional and Weston A. Price Chapter Leader in Colorado Springs, CO. Visit her website at Also check out Maria’s Cook Your Way to Wellness DVD (also available as an e-learning course) and be sure to follow her Tips from the Traditional Cook blog.
Products by Maria Atwood

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