Ever wondered what acorns taste like? No? I expected that, but today we’re going to explore some acorn benefits that might surprise you, and maybe inspire you to give them a try.

It’s October and officially the start of our journey into winter… Autumn. Many people don’t like this time of year, despite the colours and the magic of it all, we know that there’s a long Winter up ahead. Personally, I love it! The variety, and the rainy weather, and the colours, and also the harvest…

What harvest? Well I’m so glad you asked, because there is a surprising variety of things to forage for in the Autumn. One none other than the humble acorn itself!

And before you ask, no, I’m not “nuts!” (get it?)

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Acorn Benefits, Intake, and Side Effects

Scientific Name: Quercus (Robur, Rubra, Velutina… all others), Lithocarpus

Family: Fagaceae

Distribution: Great Britain, Europe, The Americas, Parts of Africa and Asia.

Identification: Red stems and (sometimes slightly
reddened) palmate sets of leaves, divided in 3. Distinctive bright
pink flowers appear throughout Spring, Summer, and Winter.

Nutritional Composition*: B-Vitamins (B1, B2, B3, B5, B6, B9), Calcium, Iron, Potassium, Phosphorus, Copper, Zinc, Magnesium, Manganese, Omega-6, Omega-9 Carbohydrate, Fat, Protein (Limited Information Available*)

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Fun Fact: The (re-)rising popularity of eating acorns has its own name! Acorn eating is also called “Balanophagy”.

In the past, acorns were once an appreciated food source. They have been used in World War II by the Japanese as an alternative to rice, by the almighty Ancient Greeks (especially the Arcadians) (^), and extensively by the (super) tough Native Americans!

Now, some people enjoy them roasted, as a coffee alternative, and even ground as a useful, healthy flour substitute. In ancient times, some cultures even made bread with the stuff. Don’t underestimate their versatility, they make excellent additions to allsorts of recipes for dinner, breakfast, and more! There are many applications that I’m sure you’ll have a use for, and they’re just as easy to find!

If you’re busy or can’t find any, then you can always Grab Some Refreshing Acorn Coffee to try them out for yourself!

They’re an excellent food source with versatility and beneficial nutrients and phytochemicals (^).

Health Benefits of Acorns:

Let’s kick this list off and explore some impressive ways in which acorn benefits health. I hope that by the end of this you’ll realise that acorns should be a welcome Autumnal treat, just as they once were in the past!

As mentioned above there are a variety of ways to use acorns, some of which I’ll be covering in future posts. Here are some useful links about how to find, prepare, and enjoy the fruit of the mighty Oak:

• How To Cook Acorns – Livestrong
• Acorn Foraging: Everything You Need to Know to Harvest One of Autumn’s Best Wild Edible Foods, with Recipes, Photographs and Step-By-Step Instructions*
  

*An easy-to-read, in-depth source of information on all things acorn – it’s a long foraging season after all!

Improve Metabolism

The first benefit that I’d like to mention is how acorns can help to improve metabolism. Being a good source of manganese, several B-vitamins, and also fibre gives acorns metabolic benefits similar to those of other nuts.

Fibre

Nuts in general contain mostly insoluble fibre, which does not dissolve in water. Lost most fibre has similar effects overall, distinguishing can be helpful sometimes. Some insoluble fibre intake with meals can help to reduce blood sugar spikes (glycemic response), and additionally helps to reduce appetite lost requiring longer to digest (^).

This can also reduce calorie intake (therefore possibly benefiting weight loss), and gives your digestive system a better chance to properly digest food and absorb nutrients.

B-Vitamins

Acorns are a good source of B-vitamins, mostly B6 and B9, but also some B1, B2, B3, and B5. These vitamins all play important roles in metabolism and energy. They’re also essential in maintaining the health of your nerves, muscles, brain, and heart!

Without Vitamin B6 (pyridoxine), we would not be able to even synthesise our cells properly (^). Having adequate B6 in the diet helps us to efficiently metabolise and digest carbohydrates, proteins, and fats(^)(^). It can help to prevent inflammation, atherosclerosis and heart disease, and improve brain health (amongst many more benefits).

By improving metabolism, this vitamin helps to make sure that we are properly digesting and absorbing nutrients. In turn, this prevents abnormal disposition or uptake of fats, carbohydrates (sugars), and protein throughout the body.

Vitamin B9 (Folate) has some similar properties to B6, and helps to regulate healthy cell metabolism in organs (^). In the body, this vitamin has a significant effect on protein synthesis, therefore being vital for proper cell formation. It also benefits white blood cells (T cells) (^). Getting folate from food sources is much better for us than taking folic acid supplements.

Manganese

In dietary levels, manganese is a trace element required for several metabolic processes.

For example, our ability to efficiently metabolise carbohydrates, proteins, and fats depends on enzymes which manganese actually helps to manufacture and regulate (^)(^)! It also plays important roles in energy and bone cell metabolism (^), and proper immune function, such as by fighting free radicals.

100g of raw acorns would provide almost 50% of the proposed adequate manganese intake for adults by the EFSA (^). That is a significant amount of acorns, but does go to show its potential.

Support Digestion

Acorns could also help to support a healthy digestive system by providing beneficial fibre. Insoluble fibre benefits digestive health by increasing efficiency and helping with bowel movements. It does this by adding bulk and attracting more water. Therefore, we find that it helps prevent constipation, bloating, cramping, and even haemorrhoid formation.

Fibre is actually a type of carbohydrate, but is often largely indigestible. As mentioned above, these carbohydrates can actually reduce appetite, and they also require a bit more work to “process”.

Now consider that this could prevent the chance of overeating or eating too quickly… Your digestive health will benefit further by including fibre in your diet, giving it an easier time.

Stronger Bones (and Bone Connective Tissue)

So, bones! They’re important. But you knew that… And you probably know that calcium is good for bones (as long as you don’t have too much)! Whilst I can tell you that acorns do contain trace amounts of calcium, it isn’t a significant amount.

What then, makes acorns good for bone health? Once again we turn to manganese, which is important not only for bone mineralisation, but also in the formation of bone cartilage (^)(^). Because of this, there are several key properties at play (^).

We also need other nutrients found in acorns for proper bone health, such as copper, B-vitamins, and phosphorus (^)(^). Overall, having some acorns now and again when the time of year comes is a good idea! The nutrients they provide support stronger bones and could therefore help to prevent osteoporosis and other problems.

Boost Energy

We already know that acorns are good for metabolism, which can help to boost energy levels. But, they also prove to be an energy-dense food. 1 oz raw acorns can provide 110 calories alone, and although they’re not eaten raw, the macronutrient composition but not differ significantly in properly prepared whole nuts.

Overall, about half of their calories come from fats, a significant amount from carbohydrates, and a small amount from protein. The majority of the fat content comes from beneficial monounsaturated fatty acids (MUFAs), specifically oleic acid. If you’ve read my article on ‘The Mediterranean Gold’, you might know that this healthy fat is a major constituent of Olive Oil. Acorns also provides some polyunsaturated fatty acids (omega-6), and saturated fatty acids.

Gram-for-gram, acorns have more carbohydrate than fat, but some of this is fibre, and naturally carbohydrates provide less energy than fats.

Antioxidants Fight Free Radicals

Several nutrients found in acorns antioxidative properties which help to eliminate harmful free radicals in the body. In effect, reducing free radicals has many beneficial and preventative effects which help to combat ageing, cellular damage, inflammation, and illness.

Acorns are not the most potent source of antioxidants, in part due to the lack of certain phytonutrients and vitamins (e.g. A, C, D, E). However, minerals in them such as copper may provide a small boost.

An interesting meta-analysis by researchers from India and Korea on free radicals and antioxidants made point of the important roles that metal ions play in supporting the protective effects of antioxidants and flavonoids (^). Beneficial enzymes require certain minerals including copper in order to efficiently convert to Radicals into to safer compounds.

Furthermore, oleic acid has also been demonstrated to reduce inflammation and support immune function (^)(^), whilst also supporting overall health. Many studies have attributed this fat to anti-inflammatory and antioxidative health benefits, including in herbal remedies (^).

Heart Health

Believe it or not, you might just be doing your heart a favour time to enjoy acorns now and again! They contain heart-healthy fats, fibre, and minerals which explain how acorn benefits heart health in multiple ways.

Copper, The Heart, and Acorns

Additionally, copper, as an antioxidant, could benefit cardiovascular health (^).

On the other hand, one review of different studies found an interesting link between copper serum levels and and coronary artery disease (^). Their findings indicated that copper is found in high amounts in those with this condition.

The significance of this is not yet fully known. One possibility suggested by some studies is that too much copper plays a role in the formation of atherosclerosis.

Fortunately, in western diets, copper often isn’t very abundant, and higher intake could provide more health benefits than any risks. The upper limit set by the EFSA is 5mg per day (and the United States IOM even 10mg). To put that into perspective, the world Health Organisation recommends a minimum of approximately 1.3g per day (^). To get even that much from raw acorns, you’d need to eat about 209g!

Not only is that a lot, but natural antinutrients found in the nut, even when leached, reduce the amount of that which we absorb. And, if your diet is high in zinc as well, you’ll be much better off at naturally regulating copper levels anyway.

Not to forget, copper deficiency has been linked to an increased risk of cardiovascular disease (^).

To conclude: The amount of copper found in acorns is beneficial for health, particularly for western populations and those with low copper serum levels or diets.

Heart-healthy Fats

Remember those fats in acorns that provide some of its calories? Not only do they provide us with energy, but oleic acid (the main type) is comparatively better for heart health than unhealthy fats (^)(^), and also than refined carbohydrates.

As a monounsaturated fatty acid, this beneficial fat may help to improve cardiovascular health (^)(^)(^). These benefits are particularly true if this fat replaces unhealthy TRANS fats such as those found in seed / vegetable oils (^).

Removing unhealthy fat from your diet will have many similar effects anyway, and is always recommended. However, it’s important not to replace them with something else detrimental, and this MUFA is a great choice.

(Don’t be mistaken into thinking that saturated fat is bad, though!)

The FDA has made health claims about oleic acid, and although they recommend reducing saturated fat, an overwhelming amount of research now dispels the myth that it is bad for us or our hearts. The practice of replacing these fats, especially with refined carbohydrates, has highly negative impacts on cardiovascular wellbeing.

Oleic acid is thought to be one of the main reasons that olive oil is so good for us (^)(^)(^). Much as this oil (important in the Mediterranean Diet) is beneficial, oleic acid from acorns might have similar effects.

Fibre Reduces the Risk of Cardiovascular Disease

Remember how we mentioned insoluble fibre? Well, here it makes another appearance, too! A range of meta-analyses and studies demonstrate that the higher fibre intake is correlated with lower cardiovascular disease risk (^).

It’s not just insoluble fibre that helps, though. Both soluble and insoluble dietary fibre effectively improve cholesterol profile, especially by reducing LDL levels (^). This is important for many people who have large LDL cholesterol particles (often due to diet).

One study found that patients with cardiovascular disease, when compared to those without, had lower intake of both fibre and MUFAs (^).

Brain Health

Acorns contain brain-boosting fats, as in most nuts. If you read about my best foods for brain health, then this to come as no surprise. Certain foods have impressive benefits for our brains, and nuts are a whole category!

Read: What Is the Best Food for Brain Health?

Now, you’re probably expecting to hear more about oleic acid. And although I don’t want to sound like a broken record, I’ve got to go by the research!

Before I carry on, do note that anything in too high amounts is negative. You’re unlikely to get too much of this from nuts, but you shouldn’t go binging on olive oil in unnecessary amounts, for example.

Back on track: Monounsaturated fatty acids

MUFA’s, including oleic acid specifically, have been demonstrated in studies to benefit brain health.

One study published in the American Academy of Neurology brought light once again to the traditional Mediterranean diet. In Southern Italy, they found that increased MUFA intake appeared to help protect the elderly population from cognitive decline (^).

Another study conducted in France, once again on behalf of the same Academy, found some impressive results. Olive oil consumption and also plasma oleic acid was measured in participants, and the correlation was found in the amount of stroke incidents that occurred (^).

According to the data, higher plasma oleic acid was associated with lower incidence.

As we can see, it’s noteworthy that oleic acid could mean that the acorn benefits brain health. One study noting the content of this MUFA in acorns mentioned the content, and commented on this nut’s health benefits (^).

Acorn Side Effects

Above we have listed some of the Acorn benefits for health. As with any food, though, especially a new one, there are potential adverse effects or reactions worth knowing of.

Allergies

First and foremost, if you have a nut allergy of any kind, you should not try to eat acorns. They are a true nut, and therefore may cause an allergic reaction and some people. If you would like to try them, always make sure that you have confirmed with your healthcare practitioner that doing so is safe.

Tannin Content – Why To Prepare Acorns Properly (It’s Easy)

Toxicity is also a possibility from raw acorns due to the high tannin content.

Tannins (i.e. tannic acid) are found in acorns and oak leaves alike, and are responsible for giving them a notably bitter taste. To get rid of the bitterness and the tannins, acorns should be leached, which makes them edible (^).

Most of the time, leaching means soaking or boiling the nuts, and is a straightforward process which is well worth the effort. You can find some great information on it from Honestfood.net: ‘The Mechanics of Eating Acorns’.

Whilst eating a few raw acorns shouldn’t have any adverse effects in those without medical conditions or allergies, it’s still not recommended and it won’t taste very nice. Tannins also bind to iron, so which prevents iron from being efficiently absorbed in the body.

Therefore, consuming too many tannins, especially with or around meals, could be a risk factor in anaemia. Doing so is associated with digestive upset such as constipation, and nausea. Forage only the ripe, brown acorns, as the younger green ones have a higher tannin content.

Also, just be aware of worms. Wild food is fun, but sometimes we’re beaten to it – that’s part of the adventure. You should be able to spot worms if there are any holes in the shell. If you find any of these acorns, leave them be (or discard them).

Recommended Intake

There is very little information on a recommended intake for acorns. For the most part, it should just come down to using your own judgement. You wouldn’t eat more than 300g of almonds (for example – and that’s still a lot), so why would you acorns?

As long as you’re leaching them properly, the tannin content shouldn’t cause a problem. If you are concerned about too much copper, remember that is unlikely you would even consume the amount necessary for the daily minimum intake. To get to the EFSA’s upper guideline for copper intake, you would have to eat over 800g of acorns on average. Yeah… No thanks!

There is very little information on a recommended intake for acorns. For the most part, it should just come down to using your own judgement. You wouldn’t eat more than 300g of almonds (for example – and that’s still a lot), so why would you acorns?

My Recommendation?

The classic saying of “moderation in all things” is a good example for certain foods, and is probably good advice here, too. That doesn’t mean that you can’t enjoy them, now, does it?

So go out there, I encourage you, and try something new this autumn. Who knows? You might just find an interest in acorns the last you until Summer (and then again), or even better, an interest in foraging! It’s a great way to connect a nature and explore or a new world of cooking, nutrition, flavour, and good health and mindfulness.

Remember to Forage Sustainably and Responsibly (Guidance by Woodland Trust)

You can always simply Get Some of Your Own Acorn Coffee, if that’s what you’re after. That is a preferable process for some, and still allows you to enjoy the benefits.

In a Nutshell (I made this pun before, too!)

Acorns are today perhaps an underappreciated food source, and at least misunderstood. They have a very interesting history and have been enjoyed by many healthy cultures, including the Native Americans and the Ancient Greeks!

The humble acorn benefits health in a number of ways, just as these people knew. They provide a wealth of nutrition, including healthy fats, carbohydrates, vitamins, and minerals. Remember to avoid them if you have a nut allergy, and always prepare and forage for them properly.

It’s October, and the new Autumn, so why not try something seasonal, and something new! You can porridge for acorns right up until Summer, and then you’ll have to wait. But, summer is just an open door to more things to enjoy!

Until next time, stay healthy
James