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Oat Milk Dangers

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When searching for a dairy free alternative, oat milk springs to the top of the list as it has a creamy texture that makes it suitable for hot beverages, cereals and much more. Apart from the oat milk benefits, oat milk dangers simply can’t be ignored. 

What are oat milk dangers? Oat milk is not good for someone with celiac disease or gluten intolerance. Also, commercially manufactured brands of oat milk are high in added sugar.

Widely proven are the benefits of oats and oatmeal, but there are often negative effects associated with the positives. Oats side effects include the potential risk of allergy, sensitivities and upset stomach.

This article explores oat milk and the possible dangers associated with its consumption. 

Does oat milk make you gain weight?

The simple answer to this question is, no. Consuming oat milk won’t make you gain weight because it doesn’t contain nutrients required by your body to put on excess weight. 

The major point of contention would be the amount of sugar added to store bought oat milk. Purchasing flavored or sweetened oat milk can be detrimental to your weight loss goals.

Oat milk is relatively low in calories along with sugar and fat. In fact, oat milk can help you shed a few pounds if you are on a weight loss regime.

But it has enough fiber and protein making it suitable for your body to lose a few pounds. A single cup of oat milk contains plenty of essential vitamins such as A, B12, and D along with minerals like iron. 

Oat milk typically contains more calcium with almost no fat compared to cow’s milk because it is typically added or fortified into the beverage by the manufacturer. Calcium strengthens the bones, and because oat milk is low in calories, sugar, and fat but rich in fiber and protein, it can make your body lose some weight rather than gaining.

Can oat milk upset your stomach?

Yes, oat milk causes upset stomach resulting from sugar and fiber not breaking down easily in your stomach. As it is carried through the large intestine, symptoms of intestinal gas, bloating, flatulence, burping, and stomach pain can occur. 

Furthermore, any toppings, mix-in or other ingredients included with the oat milk may not mesh well together. As the combination of foods digests, the interaction may upset your stomach.

Soluble fiber, mainly in the form of beta-glucan, present in oat milk is a kind of carbohydrate present in the whole grain. Although they provide you with many health benefits, soluble fiber can upset your stomach. 

The soluble fiber absorbs excess water, turns it into gel-like substance, and resulting in an effect that slows the digestion process. As such, you can experience bloating, gas, and stomach cramps.

If you are intolerant or allergic to oats, you can experience other kinds of digestive problems such as vomiting, nausea, and severe stomach pain. Keep in your mind that if you are intolerant, oat milk irritates your digestive system and even causes symptoms that may not surface for a few hours.

Why is oat milk bad for you?

In general, oat milk is a healthy vegan beverage. It is gluten, dairy, lactose, nut and soy free. Purchase unsweetened brands or make your own using rolled oats, but oat milk is healthy when consumed in moderation.

However, oat milk may not be as healthy for you as the product claims. This healthy-sounding food may have you believe the different health benefits, but in reality, the high carb and sugar count can be bad for your health when used in excess.

Sometimes commercial oat milk products aren’t gluten-free either. That way, it causes serious digestive problems if you have celiac disease or other kinds of gluten sensitivity issues. 

Furthermore, flavored oat milk contains the highest amount of carbohydrates and calories. The sugar content in oat milk could be natural, but it is rich in carbohydrates. 

As such, the stomach finds it hard to break down carbohydrates, which ultimately leads to gas and upset stomach. 

If you are allergic to oats, you may experience different kinds of digestive issues resulting in bloating, cramping, diarrhea and vomiting.

Oat milk dangers

What are the side effects of oat milk?

Oat milk is made from whole grain oats. Though the list is short, there are a few side effect of oats and disadvantages that you should be aware of:

  • Doesn’t contain much nutritional value – Compared to cow’s milk, oat milk doesn’t have enough calcium. Most surprisingly, a major portion of the nutrients gets eliminated on the way to the final product. As a result, manufactured oat milks are fortified with vitamins and minerals to increase nutritional value, however homemade oat milk will lack the nutrient enrichment.
  • May contain gluten – Oats themselves are gluten free. Sometimes they get cross contaminated with wheat on shared harvesting or packaging equipment. Therefore, the oat used for making the milk is no longer gluten-free and may cause sensitivities to flare up.
  • More calories – Remember that unsweetened oat milk has a higher number of calories compared to unsweetened coconut, soy, almond, or rice milk. The amount is minimal but noteworthy, so take it into account when closely monitoring caloric intake.
  • Quite expensive – Oat milk is more expensive than cow’s milk. A quart of oat milk can range from $3, therefore a gallon can set you back almost $10, now that’s a big investment!

Oat Milk Diarrhea

Certain commercial oat milk products contain higher amounts of sugar. That’s unhealthy because sugar in excessive amounts can reverse the health benefits of oat milk. 

Apart from this, not all the products are free from gluten. If you are gluten intolerant, it causes issues related to your stomach like diarrhea.

Therefore, don’t forget to check the label to ensure that the product is gluten-free and unsweetened before buying. Gluten-contaminated oat milk can cause serious digestive problems for people suffering from celiac disease and they find it hard to digest and can develop stomach cramps.

What’s more problematic is that sometimes people suffer from vomiting, bloating, and diarrhea. To keep diarrhea at bay, you can try to make oat milk at your home. 

That way, you can make oat milk that is100% free from gluten. However, homemade oat milk is not nutritious compared to the commercial ones as it is not enriched with added vitamins.

Spoiled Oat Milk

Spoiled oat milk gets a yellow tint quite darker than the usual beige cream color. If you notice a deflection in color, smell, and taste, it is confirmed that your oat milk has expired and is no longer suitable for consumption. Drinking expired milk is not a good idea.

Although oat milk can be sustained as healthy milk, it has a short expiration date. Oat milk kept in a refrigerator in a well-sealed condition, may last for up to 5 days, but certain brands produce oat milk that can last between 7 to 10 days.

To increase the amount of time that oat milk will last, store the beverage in an airtight container and keep in the coldest part of the fridge; generally the center back of the appliance, not on the door which is susceptible to large temperature fluctuations.

After the expiration date is over, stay away from the oat milk, or else it can make you sick. If you take a chance, be sure to observe for signs of spoilage that signify that oat milk has gone bad.

The obvious indications include color, texture, off putting smell and foul taste. Always remember that drinking spoiled beverage can attract oat milk dangers and make you sick. 

Consuming expired milk may cause food poisoning in some situations that lead to symptoms such as severe stomach pain, vomiting, nausea, and diarrhea.

Oat Milk Dangers: Final Thoughts

Oat milk is a widely accepted alternative to normal dairy milk because it is vegan, nut free, soy free, gluten free and also associated with a number of health benefits. Additionally, you can prepare it in your home with ease. 

Despite the positive connections, oat milk is not for everyone. Most of the commercial products contain sugar in excessive amounts.

Besides, these products are not always gluten free. If a person is wheat intolerant, that could cause a lot of trouble. 

If you get affected by the side effects, stomach cramps, gas, bloating, vomiting, nausea, and even diarrhea may result from consuming oat milk. Therefore, have a clear understanding of the product to avoid any kind of undesirable situations.

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Thursday 4th of August 2022

Do you have any thoughts on oat milk causing head to toe welts and hives as a side effect?


Saturday 3rd of September 2022

@Joshua, @Stacey, I'm having the same issue, hives & welts... random locations daily. So bizarre!


Thursday 4th of August 2022

Are you sure it is from the oat milk? Sounds like a severe allergy or possible reaction to something else. Either way, this is something you should consult with a physician right away. Wishing you the best!

Carla Braun

Wednesday 16th of February 2022

Two full days of stomach pain and explosive 💩. Won't try oat milk again!


Monday 13th of March 2023

@Carla Braun, Same thing happened to me. I was sick with severe stomach pain bloating and gas.


Sunday 3rd of July 2022

@Pilar, Oatly has 3 versions. The low fat oatly milk has no oils.


Wednesday 27th of April 2022

@Carla Braun, Try an oak milk without oil. Oatly makes me terribly sick, but I have had good luck with other brands. Best one available at my store is Planet Oat unsweetened, it doesn't bother my gut at all.


Thursday 17th of February 2022

Ya that is definitely one of the most common dangers. Drinking a full cup right off the bat tends to do that if you are not familiar with the beverage. If it is not allergy related, then try a few sips at a time and build up to half a cup over the course of a week, and then a full cup over two weeks time. Incremental increases will give your body time to get used to processing the oat beverage.


Thursday 13th of January 2022

This article answers the questions that I had about oat milk dangers.


Friday 7th of January 2022

Seems that maybe oat milk is upsetting my stomach. They all seem to have a large amount of oils in them as well. I wonder if this is part of the problem as well?


Friday 7th of January 2022

Hello Doug, thanks for sharing. I would tend to agree with this concern as well. Canola, otherwise known as rapeseed, is the most commonly used oil in oat milks. The reason being that it is relatively neutral in taste, but not necessarily the healthiest option available. It may sit heavy in the stomach leading to upset or indigestion problems.


Wednesday 3rd of November 2021

this was good information to now what oat milk to buy an witch one to stay away from, though I don't have a gluten allergy, I find dairy milk to be an issue for me, an switching to oat milk has proven helpful with my coffee, but some oat milk has a lot of extra additives, gluten free California oat milk seems to be the right one for me, I drink it in my coffee every day.


Wednesday 3rd of November 2021

Thank you for sharing your experience. Many people have switched away from dairy milk, and oat milk is a dairy-free beverage alternative that has become extremely popular for that reason.