Soaking Oats Overnight: What, How and Why?

(Last Updated On: August 3, 2018)

Oats are a common staple in millions of kitchens. They make for a quick and easy breakfast, and they’re versatile enough to be on your lunch and dinner menus too. But oats have a sinister secret. And if you don’t prepare oats properly, they’ll launch stealth attack after stealth attack, robbing you of precious nutrients, as easily as a nimble fingered thief picks pockets on a city street.


Phytic Acid The Bad Guy In Your Breakfast

Oats are a seed, and like all seeds (grains, nuts and legumes) they contain a substance called phytic acid. Phytic acid is an anti-nutrient. Some people have favorable gut flora that can break down the phytic acid, but most people don’t. The phytic acid in oats combines with calcium, zinc, magnesium, iron and copper in your gut and blocks your body’s ability to absorb those nutrients Phytic acid grabs onto whatever minerals it finds in your digestive tract and keeps a tight hold, until your body excretes the whole nutrient-rich package.

In some cases consuming animal products containing vitamins A and D can help to mitigate the action of phytic acid. The more nutrient-rich your diet, the better able you can cope with the effects of phytic acid.

Inability to absorb these important nutrients over the long term is implicated in many, many serious health problems.

Estimates of the average daily phytate intake range between 630 and 740 mg per day, in the United States and the United Kingdom. It’s lower in Finland, Italy and Sweden at 370 mg, 219 mg,180 mg per day respectively.

And given the low levels of nutrients in the standard American diet, it’s fair to say that unprepared grains are not a good idea for most people.

Nutritionist may like to tout the health benefits of eating ‘healthy whole grains’, but the truth is, there is no such thing. Even without the problematic phytic acid, whole grains can play havoc with your insulin levels. Dr William Davies, in his book Wheat Belly, revealed the startling fact that two slices of wholegrain bread raises blood sugar more than 6 teaspoons of white sugar. And yet people with type 2 diabetes and prediabetes are told to go ahead and eat wholegrain bread.

But the focus of this article is on oats and their phytic acid, so I better get back on topic!

Our ancestors knew all about the problems associated with phytic acid. They may not have known its name, but they recognized the mineral deficiencies that it caused and developed food preparation techniques that inactivated it.

Phytic acid is essential for plants. It’s how they store phosphorus. Without phosphorus plants will not grow. It’s an essential nutrient for us too by the way. Actually there is concern that we may not always have access to the humongous amounts of phosphorus necessary for our modern farming techniques, but again that will take us off topic, so if you’d like to know more about the phosphorus shortage, (that according to some is only a few decades away), then you can head over to The Conversation and get yourself up to speed.

In humans and animals without multiple stomachs the phosphorus in plant tissues is tightly bound in the phytic acid molecules and is not readily available for us to absorb. Those phytic acid molecules also reach out and grab onto the other nutrients already mentioned, making them unavailable for absorption too. When phytic acid is bound to a mineral, it’s known as phytate.

As an example, consuming 5-10 mg of phytic acid can reduce your body’s uptake of iron by 50%.

Phytic acid’s machinations don’t stop there though! As if stealing your minerals wasn’t bad enough, greedy phytic acid, inhibits the enzymes that you need to digest the rest of your food.

It messes around with

  • Pepsin that’s needed to break down proteins in your stomach.
  • Amylase that’s needed to breakdown starch.
  • Trypsin that digests protein in your small intestine.

Can you imagine how a breakfast of hearty oatmeal could be a problem, especially for growing children and pregnant women?

I know that I’ve made phytic acid out to be the bad guy, and it is for us. But it’s absolutely necessary for plants and for their seeds. Those seeds (grains, legumes, nuts) don’t exist for our benefit, they exist to make more bean plants, more corn plants, more grasses (oats, wheat, rye, barley etc) and more hazelnut, almond, and walnut trees. And those seeds have a tough journey. Everything wants to eat them!

Seeds also need to germinate at the right time to allow them the best chance of making a plant that can grow to maturity and produce more seed.

The mechanisms like phytic acid that plants use to protect their seeds and make them less digestible and able to pass through the systems of creatures that are likely to eat them, and emerge intact in their poop, makes the survival of future plant generations possible, it just makes life a little more difficult for us.

We put our kids in car seats and keep their vaccinations up to date to ensure our genes live on. Plants wrap their DNA in protective bundles too.


Phytase To The Rescue (Sometimes)

Phytase is an enzyme that is found in plants that contain phytic acid. It has the ability to neutralize the phytic acid, which prevents all of the mineral and enzyme problems and frees the phosphorus in the plant, making it available for absorption.

Mammals with multiple stomachs are able to deal easily with phytic acid because the microorganisms in their rumen produce plenty of phytase. We humans with our single stomachs also produce phytase, we just don’t produce much, and certainly not enough to cope with our high grain diets.

Rodents who happily munch on whole grains produce 30 times more phytase than we do. Poultry, (fed exclusively on grains in industrial farming systems) don’t produce phytase. It has to be added to their feed. Maybe that’s one reason why laying birds are so frequently culled after one year’s egg production, (although the use of phytase supplementation has been increasing). They’re so utterly mineral-depleted that their egg production falls off a cliff. I know from my own experience of raising laying hens, that a well-fed, free-ranging flock will produce eggs at a steady clip right up until they’re 3 years old or so, then their production will start to decline.


Phytase In Oats


Sprouting is often recommended to activate phytase activity, which lowers the amount of phytic acid present. But that only works in the kinds of grains that contain sufficient phytase to begin with, and it only reduces the amount, it doesn’t eliminate it all.

Oats are very low in phytase, so even if you wanted to sprout them, there wouldn’t be enough to combat the phytic acid present.

And that small amount of phytase that is present in the oats is destroyed in commercial oatmeal production. So you’re really starting at square one when it comes to making sure that your morning oatmeal doesn’t pack a phytic acid punch.

The good news is that by preparing foods containing phytic acids properly you can eliminate most of the phytic acid and avoid the problems that it causes. Taking the time to ‘nuke’ phytic acid means that your body can get the nutrition that it needs from all of the foods that your eat.


We Used To Know This Stuff!

Cultures that have retained their traditional food preparation techniques still soak their grains. Even in our non-traditional world Quaker used to (prior to the 1950’s) include instructions on how to soak oats right on the box, and soaking grains, especially breakfast oats was a widespread practise prior to the second world war.

That beneficial practice fell out of favor as people got too busy, and convenience foods and quick meals took hold.

Now, thanks to the internet and a renewed interest in true healthy eating, people are waking up to the misleading healthy eating guidelines offered by the food pyramid and the newer Myplate. A new generation is relearning the old methods that helped people get the most from their food.

We owe sincere gratitude for the pioneering work of Dr Weston Price, who investigated the traditional diets of cultures all around the world, and identified grains and improper preparation techniques as one of the main causes for the degenerative disease epidemic that blights much of the western world.

Heart disease, type 2 diabetes, hypertension and stroke, tooth decay and periodontal disease, osteoporosis to name a few; none of these conditions are normal, they’re not just a part of getting older. And they are practically unknown in indigenous tribes that still consume a traditional diet.

We laud the scientists and doctors who conjure up expensive drugs to control these types of disease conditions. They’re heroes curing the world of its ills. But they just wouldn’t be necessary if we ate the foods that we were designed to eat, and if we took the proper care to prepare foods containing anti-nutrients properly.

We’re using a hammer to crack an egg! It’s not as though this information has only just been discovered. We’ve known about the harmful effects of improperly prepared seed foods for thousands of years. And we’ve known what to do about it too.

You’ll often see the recommendation to soak oats and other grains and legumes in water overnight to inactivate the phytic acid. But soaking in water alone won’t get the job done.

The soaking has to be done is an acidic medium. AND you need to add additional phytase to the mix. And the room temperature needs to be right.

Which all sounds like a big pain in the… Doesn’t it. Well it’s not too much trouble actually, but it’s still a bit of a grind when you’ve had a long day and you just want to sit down and switch off. Which is why everyone stopped soaking their grains in the first place.

It’s a fact of life that we can be aware of the things that we should do for our health and well being, but we don’t always do them. Especially when it’s easier and often a lot more pleasurable to do something else instead.

Go to the gym? Nope let’s Netflix and chill with a bag of chips and a beer.

Salad for lunch? Are you crazy, don’t you see the hot dog vendor on the corner!

They say the ‘road to hell’ is paved with good intentions, but we can rewrite that as the ‘road to health’ and be close to the mark.

Don’t worry though, I’m a non-perfect human just like you, so I’ve got you covered on that front, and you can skip down to the last section if soaking oats sounds like too much of a slog for your tastes.

One last thing before you skip down though. Soaking oats and other grains will leave you satisfied for longer. Eating a bowl of regular oatmeal for breakfast can leave you watching the clock for a mid-morning snack. Soaked oatmeal will see you through to lunch and beyond with ease. So you’ve got less chance of reaching for a sugary snack, which is definitely a big plus.

Okay then, scroll if you must, otherwise let the soaking begin.


How To Soak Oats To Eliminate Phytic Acid


What to use for the acid medium?

You can use dairy based acid mediums

  • whey
  • whole milk kefir
  • cultured buttermilk
  • whole milk yogurt

Or non-dairy acid mediums

  • lemon juice
  • raw apple cider vinegar (ACV with the ‘mother’ in the bottle as opposed to the filtered kind)
  • coconut milk kefir
  • water kefir

Some people find that the dairy based acid mediums give the oatmeal a sour tang that they don’t much care for. Using the non-dairy acid mediums doesn’t produce that flavor.


What to add for the Phytase?

  • rolled rye flakes
  • ground buckwheat
  1. Measure out your oats by the cup then place them in a bowl and cover with warm water.
  2. For each cup of oats add one tablespoon of dairy based or non dairy based acid medium.
  3. Add one tablespoon of phytase.
  4. Give a gentle stir and then cover the bowl.
  5. Soak for at least 24 hours at room temperature. If it’s Winter and you don’t leave the heat on during the day, put the bowl in the oven with just the oven light on. That should keep conditions warm enough.
  6. Drain in a fine mesh strainer and then rinse.

See? I told you that it’s not too much effort, I think that remembering to do it is the hardest part. If you quickly set up the next day’s oats to soak as you’re clearing away breakfast, then you won’t forget about it. Soaking the oats could be a chore that you set for your kids to do. Kids generally like mixing up big bowls of stuff and the recipe is so simple to follow that they shouldn’t have any trouble getting it right.


Vitamin C Can Eliminate Phytic Acid Too

Vitamin C

I love vitamin C, or ascorbic acid. It’s one heck of a powerful vitamin. So powerful that it’s credited with saving the life of a New Zealand dairy farmer critically ill with swine flu.

Doctors had declared Allan Smith a terminal case. There was nothing further they could do for him and they were preparing to turn off life support – very much against his family’s wishes.

Luckily for Allan, his family were fighters and boy did they fight for his life. They had to take legal action against the hospital to keep life support on and to get Allan the one treatment that they thought might possibly save him. That treatment was Intravenous vitamin C.

Doctors didn’t think that it would work and were unwilling to even try it, even though they could offer nothing further from their arsenal to save Allan’s life. Well you must have guessed how this story ends. The vitamin C did work! And Allan’s remarkable return from the brink of death has become known as “one of the most remarkable and controversial turnarounds in New Zealand medical history”.

The medical establishment tried to frame it as just one of those inexplicable things and said that the vitamin C had nothing to do with his recovery.

A network news channel in New Zealand made a documentary about Allan’s ordeal and you can find it on Youtube if that kind of thing interests you.

And that nice little story leads me to another one of vitamin C’s abilities.

In addition to knocking out swine flu, this superstar vitamin can also knock out phytic acid. Studies have found that consuming vitamin C with a meal will counteract the effects of the phytic acid.

Taking 80mg of vitamin C with a meal was sufficient to prevent 25 mg of phytic acid from getting up to its tricks.  Phytate levels in dry oats vary between 0.88 – 1.16g per 100g.

Oatmeal aside, If you remember from earlier in the article, the estimated total levels of phytate consumption for people in the US were around 630 – 740mg per day.  

Some of that will be mitigated by the phytase in the foods containing the phytic acid but you can see why supplementing with vitamin C is a good idea.

80mg is right around the government’s RDV for vitamin C intake but in truth it isn’t much at all. For optimum health most sources recommend taking at least 1 gram per day, and much more if you’re unwell or if you have health issues.

It’s a good idea to split vitamin C up over the day since your body just excretes what it can’t use up fairly quickly. If you take a small amount throughout the day, then you’ll always be in phytic acid ready mode. Because even if you fully intend to soak every grain and legume from now own, there will be times that you forget, or you simply can’t be bothered. Or you’re out to dinner or on vacation where you can’t very well insist that the kitchen soak your seeds.

If you soak your oats or make sure that you take vitamin C, then oats are a great source of nutrition and you can enjoy them without worrying,

Happy eating!

Written by Irina Radosevic MD
Irina graduated from the University of Belgrade, School of Medicine as a Doctor of Medicine (MD) and spent over 3 years working in the Clinical Hospital Center Zvezdara, in the Department of Emergency Medicine. She also undertook a postgraduate in Cardiology from the same University and had previously worked for over a year as a Physician and Nutritionist Dietitian for the Fitness club Green Zone. She eventually left her chaotic but fulfilling job in the ER to pursue her passion of writing, travelling and mountain climbing which has included writing a first aid course for the alpine club of Belgrade. Irina currently works as a VA for PintMedia focusing on medical and travel writing. Feel free to connect with Irina on LinkedIn and FaceBook. Her CV can be seen here.