Can You Eat Acorns?

Health Line

12-06-2025

Acorns are the nuts of oak trees, which grow abundantly across the globe. Though these nuts are packed with nutrients, it's often debated whether they're safe to eat.
Once a staple food for various societies, acorns are not as frequently consumed today.
This article tells you whether acorns are edible and explores their nutrients, benefits, and dangers.
Acorns are generally safe to eat
Acorns have gained a bad reputation because they contain tannins — a group of bitter plant compounds that may be harmful when consumed in high amounts.
Tannins are considered antinutrients, which means that they reduce the body's ability to absorb essential nutrients from food.
Additionally, consuming high amounts of tannins may lead to adverse health effects in humans and animals, such as severe liver and kidney damage.
However, most of the tannins leach out of acorns when they're prepared for consumption — often by soaking or boiling. While no studies exist on the toxicity of raw acorns in humans, these nuts are rarely eaten raw.
In fact, people have been safely consuming acorns for thousands of years.
Acorns are highly nutritious
Though the exact nutrient profile depends on the species of acorn, all are packed with essential nutrients.
Plus, these nuts are low in calories. Most of their calories come in the form of healthy unsaturated fats.
A 1-ounce (28-gram) serving of dried acorns contains the following nutrients:
Calories: 144
Protein: 2 grams
Fat: 9 grams
Carbs: 15 grams
Manganese: 17% of the Daily Value (DV)
Potassium: 4% of the DV
Vitamin B6: 12% of the DV
Folate: 8% of the DV
Scientists have also identified numerous beneficial plant compounds in acorns, including catechins, resveratrol, quercetin, and gallic acid — potent antioxidants that can help protect your cells from damage.
These antioxidants are linked to numerous health benefits, such as a lower risk of heart disease, cancer, and diabetes.
Potential benefits of acorns
Acorns may have several health benefits as long as they're properly prepared and not eaten raw.
May improve gut health
The bacteria in your gut play a key role in your overall health. An imbalance of these bacteria has been linked to obesity, diabetes, and bowel diseases.
Acorns are a great source of fiber, which nourishes your beneficial gut bacteria.
Additionally, acorns have long been used as an herbal remedy to treat stomach pain, bloating, nausea, diarrhea, and other common digestive complaints.
In a 2-month study of 23 adults with persistent indigestion, those who took 100 mg of acorn extract for 10 days had less overall stomach pain than those who took a starch capsule when this was assessed 2 months later.
However, this study used highly concentrated extract. It's not known whether whole acorns would have the same effect.
More research on their digestive effects is needed.
Rich in antioxidants
Antioxidants are compounds that defend your cells from damage caused by potentially harmful molecules called free radicals.
Acorns are rich in antioxidants like vitamins A and E and numerous other plant compounds.
One animal study noted that an antioxidant-rich acorn extract reduced oxidative stress in rats with reproductive damage.
That said, human research on the anti-oxidative and anti-inflammatory effects of acorns and acorn extract is needed.
Abundant in the wild
Over 450 species of oak worldwide produce acorns. These are mainly in the Northern Hemisphere.
From fall to early spring, you can find hundreds — if not thousands — of mature acorns on the ground below these trees. These nuts are considered safe to forage, but you should watch out for rotten ones. Green, unripe specimens should likewise not be gathered.
If collected in the wild, acorns can be a free, nutritious, and sustainable local food choice.
Potential downsides of acorns
Although acorns offer several benefits, they also have potential drawbacks.
Raw ones may be unsafe
As mentioned above, the tannins in raw acorns function as antinutrients, reducing your absorption of certain food compounds.
Older studies have linked tannins to certain cancers and may cause liver damage when consumed in high amounts. However, more recent research suggests that tannins may actually have an anticancer effect. Nevertheless, it is not recommended to eat raw acorns.
Some people report nausea and constipation from raw acorns, though research has not confirmed this. What's more, the tannins give these nuts a bitter flavor.
Boiling or soaking your acorns can easily remove the tannins. This process eliminates their bitterness and makes them safe to eat.
May cause allergic reactions
Acorns are a tree nut, one of the most common allergens worldwide.
In fact, between 0.5% and 1% of the US population is allergic to one or more tree nuts.
Allergic reactions to tree nuts range from mild itching, scratchy throat, and watery eyes to anaphylaxis — a life-threatening response that can cause extreme difficulty breathing.
If you're allergic to other tree nuts, you should avoid acorns unless cleared to consume them by your healthcare practitioner.
Can be difficult to prepare
Collecting and preparing acorns can be time consuming. Though abundant in the wild, they're not commonly sold in grocery stores.
You may need to order them online if you're unable to forage your own.
You also have to leach them of their tannins to reduce their bitterness and ensure that they are safe to eat. This can be done by boiling or soaking.
Though this process is quite simple, it may feel cumbersome — especially since other nuts are readily available and much easier to eat.
How to eat acorns
Raw acorns contain high amounts of tannins — a chemical that makes them bitter and possibly unsafe to eat in large quantities.
Nonetheless, it's possible to remove the tannins in several ways.
One of these methods is boiling. Foragers and harvesters often recommend the following steps:
Look for fully mature, brown acorns with the caps still attached. Avoid green, unripe acorns, as these are higher in tannins.
Rinse your acorns thoroughly to remove contaminants such as dirt and small insects. Then, throw out any rotten nuts.
Remove the hard shells using a nutcracker.
Boil the raw acorns in a pot for 5 minutes or until the water turns dark brown. Strain the nuts using a colander, discarding the dark water.
Repeat this step until the water boils clear.
After the tannins are leached out, the nuts are considered safe to eat. You can roast them in the oven at 375°F (190°C) for 15–20 minutes for a quick and nutritious snack.
To satisfy your sweet tooth, try roasting them with honey or tossing them with cinnamon sugar after baking. Dried acorns can also be ground into flour for use in breads and pastries.
The bottom line
Raw acorns are considered unsafe due to their tannins, which are toxic if consumed in high amounts.
However, you can remove the tannins by boiling or soaking. Properly prepared acorns are perfectly edible and full of nutrients like iron and manganese. Delicious roasted, they can also be ground into flour.