Popcorn contains high amounts of resistant starch, fiber, and other vitamins and minerals. It’s a “whole-grain” and can be consumed as part of a healthy diet.
A corn starch product known as Hi-Maize is used in many gut health studies. Hi-Maize is the starch from corn that is bred to be high in resistant starch, you can even buy Hi-Maize in 5-pound bags and use it in smoothies or even for baking, and it retains its RS. But what about popcorn? Until recently, nobody knew. Now, thanks to some great research, we know!
Don’t feel like reading?: 4 cups of popped popcorn (one serving) contains roughly 4g of resistant starch (RS3) and 7g of other fibers, making it very high in both fiber and RS. Popcorn is a good snack! Just stay away from the artificial flavors and especially artificial butter. Best bet is to make your own with a hot-air popper or a silicone microwave popper. If you use the oil and hot pan method, I suggest using red palm oil or coconut oil.
The question about RS in popcorn has come up several times in the last couple years. I have never been able to find a paper in which the RS content of popped popcorn was examined. Corn is a funny grain, its starch contains very little RS due to its shape, structure, and high amylopectin content. A special corn has been bred (Hi-Maize) that contains more amylose starch, and thus it is a great source of RS. Hi-Maize, in fact, is the de facto “king” of RS, used in nearly all studies performed on RS in the last 30 years. It has a stable RS content and can even be used in baking.
Due to the fact that normal corn varieties are low in RS, and knowing that when RS2 is cooked and cooled it loses most of its RS value when it converts to RS3, I assumed that popcorn was a poor source of RS, with maybe 2-3% total by weight in popped popcorn. Turns out, this is not the case!
Weights and Measures
Unpopped popcorn weighs about 40g per 1/4 cup (the recommended “serving size” listed on the label).
1/4 cup of unpopped popcorn makes about 4 cups of popped popcorn. For reference, when you go to the movies, a “small” popcorn generally contains 7 cups, “medium” 16 cups, and a “large” is 20 cups.
One rationale I used for “RS-less” popcorn was the general lack of gastric complaints by movie-goers and the sales of jelly beans over kidney beans as movie snacks. I had reasoned that if popcorn contained ample RS, there would be many complaints of flatulence by movie-goers. And it seems there are!
Maybe I just never noticed it, or never eat that much popcorn, but Googling “popcorn farts” turns up lots of humorous hits. But popcorn farts just don’t seem to be all that prevalent, otherwise you’d think people would avoid popcorn. When I was last at the movies, I was amazed at the sheer volume of popcorn being consumed!
Nutrition-wise, popcorn is great. That 4 cup single serving has:
- 110 calories
- 0 cholesterol
- 0 sodium
- 27g carbs
- 1.2g fat
- 7g “fiber”
- 4g protein
While not a powerhouse of vitamins, it does have some Vitamins A, B-6, C, and iron and magnesium.
The downside of popcorn is that it is usually salted heavily and cooked in dubious oils, then covered in a butter-flavored goo. Making your own popcorn is lots of fun and you can control all the extras. If you get a popcorn at the movies, get it un-buttered at least, and just get a “small.”
RS in popcorn
The moment you’ve all been waiting for! According to this paper sent to me by friend Barney, popped popcorn contains about 11% RS. That’s a lot more than I ever guessed!
A single serving, 4 cups popped, weighing about 40g, will have about 4g of RS (RS3 to be precise) per serving. This is roughly equivalent to the RS in a half-cup of beans or a half-pound of cooked and cooled potatoes or rice, or a half TBS of raw potato starch.
Couple this with the 7g of conventional fibers, and you have 11g of total fiber per serving. This is well on par with the other fiber giants, oats and beans.
Also, no surprise, agro-chemists are crossing regular popcorn plants with high-amylose corn, and producing popcorn with an RS value as high as 46%.
Cooking Popcorn (or is it “Popping?”)
Popcorn is a great snack, and a great source of RS. If you are looking for something to snack on at home, learn to make popcorn with as little oil as possible.
I eat popcorn regularly, well, maybe a couple times a month. If I get popcorn at the movies, it’s always a “small” shared between two people, and always “no butter, please.” At home, I find that using 1/3 of a cup of popcorn seeds makes a very big bowl and it hardly needs any salt, and definitely no butter.
I’ve tried this “bag in the microwave” trick, and it is just OK.
My favorite method of cooking popcorn is with a hot air popper. These were very popular in the ’70’s, and it’s a real shame that the fad died out. Just as with potatoes, it’s the crazy add-ons that make these foods unhealthy. With a hot air popper, you just add plain popcorn to the hopper and out comes perfectly popped popcorn. A super-treat for kids and adults. For a cheesy flavor, try some nutritional yeast flakes. Some salt won’t hurt, either.
I have a feeling that as soon as the FDA starts to recognize RS as a vital fiber source, popcorn will carry a “high in RS” label. At 11% RS by weight, it’s on par with beans as one of the richest sources of RS in common foods you’ll find. The fact that popcorn does not cause massive gas like beans must be because it is devoid of the other gas-causing substances that beans are full of (ie. raffinose). Additionally, all of the other dietary/insoluble fiber in popcorn probably helps to spread the fermentation of the RS throughout the colon, as our previous discoveries that things like psyllium husk and wheat dextrin help to ensure even fermentation when combined with RS.
So…popcorn…the perfect snack?