A lot of foods exist on a spectrum of suitability, from “really bad” wheat to “not so terrible” rice. Well, what about the rest of them? Since I get a lot of email asking whether oats and oatmeal are good for you, I figured I would dig into that question for this post.
Though I was (and still mostly am) content to toss grains on the “do not eat” pile, I think we’re better served by more nuanced positions regarding grains. Not everyone can avoid all grains at all times, and not everyone wants to avoid all grains at all times. For those situations, it makes sense to have a game plan, a way to “rank” foods.
Today, we’ll go over the various forms of oats and oatmeal, along with any potential nutritional upsides or downsides.
First: What Is an Oat?
The common oat is a cereal grain, the seed of a species of grass called Avena sativa. Its ancient ancestor, Avena sterilis, was native to the Fertile Crescent in the Near East, but domesticated oats do best in cool, moist climates like regions of Europe and the United States. They first appeared in Swiss caves dated to the Bronze Age, and they remain a staple food crop in Scotland.
Forms of Oats
There are seven forms of oats that are typically available for purchase:
Whole Oat Groats. The “whole grain” form of an oat is called a groat and is rarely sold as-is, except maybe as horse feed or in bird seed mixes. Instead, they’re sold either as steel-cut, rolled, or instant oats.
Scottish Oats. These are stone ground, which are thought to make a creamier oatmeal than steel cut.
Steel Cut, or Irish Oats. Steel cut oats are, as the name suggests, cut into a few pieces per grain with a steel blade. These retain the most nutrients (and antinutrients like phytic acid) and taste nuttier and chewier than old-fashioned oats, quick oats, or instant oats.
Old-fashioned Oats, or Rolled Oats. Rolled oats are steamed and then rolled into flat flakes.
Quick Oats. Quick oats are rolled thinner than old-fashioned oats for quicker cooking.
Instant Oats. Instant oats are rolled even thinner than quick oats, so they can be cooked with only hot water.
Oat flour. Oat flour starts with the whole oat groat and is ground into a fine powder.
Why Are Oats Bad for You?
Oats aren’t bad for everyone, but people avoid them for a few reasons. The main problems with oats are the phytic acid, which has the tendency to bind minerals and prevent their absorption. Another concern is the avenin content, which is a protein in the prolamine family that some people cannot tolerate.
As far as phytic acid (or phytate) goes, oats contain less than corn and brown rice but about the same amount as wheat.
Some say soaking is sufficient for removing a portion of the antinutrients in oats. Others say you need lactic acid fermentation to neutralize the antinutrients.
Soaking involves soaking the oats overnight in water with a tablespoon or so of acid, either from lemon juice or from apple cider vinegar.
Lactic Acid Fermentation
As I understand it, you can further reduce antinutrients by lactic acid fermentation. I’m not sure the degree to which phytate can be deactivated, but one study does show that consuming oats that underwent lactic fermentation resulted in increased iron absorption.
Other sources claim that simple soaking isn’t enough, since oats contain no phytase, which breaks down phytate. Instead, you’d have to incorporate a phytase-containing flour to do the work; a couple tablespoons of buckwheat appear to be an effective choice for that. Combining both lactic acid bacteria (whey, kefir, or yogurt), companion flour (buckwheat), water, and a warm room should take care of most of the phytate… but that’s a lot of work!
It looks like once you remove gluten, other, potentially damaging proteins become far less dangerous. One study did find that some celiacs “failed” an oats challenge. Celiac patients ate certified gluten-free oats, and several showed signs of intestinal permeability, with one patient suffering all-out villous atrophy, or breakdown of the intestinal villi. A few out of nineteen patients doesn’t sound too bad, but it shows that there’s a potential for cross-reactivity.
Do Oats Contain Gluten?
Oats are often cross-contaminated with gluten because they often grow close to one another in the fields, and seeds don’t always stay where you put them. Certified gluten-free oats are not processed in the same facility as gluten grains, and they are grown far away from wheat fields.
So, if you have celiac disease and you are going to experiment with oats, make sure they’re certified gluten-free.
Why do oats get so much praise from health organizations, like the American Heart Association?
Like other prebiotic fibers, oat bran also increases butyrate production (in pigs, at least), which is a beneficial short-chain fatty acid produced by fermentation of fibers by gut flora with a host of nice effects. Overall, I think these studies show that soluble fiber that comes in food form is a good thing to have, but I’m not sure they show that said fiber needs to come from oats.
Nutritional Profile of Oats and Oatmeal
Oats also appear to have a decent nutrient profile, although one wonders how bioavailable those minerals are without proper processing.
A 100 gram serving of oats contains:
16.9 grams protein
66 grams carbohydrate
10.6 grams fiber (with just under half soluble)
7 grams fat (about half PUFA and half MUFA)
4.72 mg iron
177 mg magnesium
3.97 mg zinc
0.6 mg copper
4.9 mg manganese
Oatmeal is a perfect example of the essentially tasteless, but oddly comforting food that’s difficult to give up (judging from all the emails I get). It’s tough to explain, because it’s not like oatmeal is particularly delicious. It’s bland, unless you really dress it up with dried fruits, sweet syrups, and other blood-sugar spiking ingredients that Primal, paleo, and keto folks would rather avoid.
I suspect it’s more than taste. I myself have fond childhood memories of big warm bowls of oat porridge steaming on the breakfast table. I’d add brown sugar, dig in, and head out to adventure through blustery New England mornings with a brick of pulverized oats in my happy belly. The nostalgia persists today, even though I don’t eat the stuff and have no real desire to do so.
Still, since I had some steel-cut oats laying around the house from a past houseguest who absolutely needed his oats, I decided to give them a shot. To self-experiment. To – gasp! – willingly and deliberately eat some whole grains. They were McCann’s Irish oats. Raw, not steamed, and of presumably high quality.
It was… okay. The liberal amount of butter I added quickly disappeared without a trace, and I had to stop myself from adding more because that would have been the rest of the stick. The berries and cinnamon looked and smelled great, but they were swallowed by the blandness. I even added a tablespoon of honey but couldn’t taste it. It was satisfying in the sense that it provided bulk in my stomach.
A half hour after, I felt kinda off. It’s hard to describe. A spacey, detached feeling? Slightly drugged? However you want to describe it, it didn’t feel right. Only lasted half an hour or so, though. My digestion was fine, and I never felt bloated besides the initial “brick in the stomach” feeling.
That’s my experience with oatmeal. Yours may be different.
My opinion of oats as a food? Better than wheat, worse (and more work to improve) than rice. I won’t be eating them because I frankly don’t enjoy them, there are numerous other food options that are superior to oats, and I don’t dig the weird headspace they gave me, but I’ll admit that they aren’t as bad as wheat. If I want starch, I’ll go for some sweet potatoes.
What about you folks? Do you eat oats? Would you be willing to soak, ferment, and cook them? Let me know how it works, or worked, out for you!
Mark Sisson is the founder of Mark’s Daily Apple, godfather to the Primal food and lifestyle movement, and the New York Times bestselling author of The Keto Reset Diet. His latest book is Keto for Life, where he discusses how he combines the keto diet with a Primal lifestyle for optimal health and longevity. Mark is the author of numerous other books as well, including The Primal Blueprint, which was credited with turbocharging the growth of the primal/paleo movement back in 2009. After spending three decades researching and educating folks on why food is the key component to achieving and maintaining optimal wellness, Mark launched Primal Kitchen, a real-food company that creates Primal/paleo, keto, and Whole30-friendly kitchen staples.