why ascorbic acid is not vitamin c

Getting enough nutrition is important. Nutrition is a building block for good health, and it absolutely cannot be overlooked!

Sometimes, if we just get a little bit more of a specific nutrient, some health issues go away completely on their own.

Vitamin C is one such important nutrient. Is every form of vitamin C good for you? Not exactly.

Especially when it comes to the most common form of vitamin C on the market and in supplements, ascorbic acid— and you’ll find here why. 

What is vitamin C, and why do we need it?

You’ll find vitamin C in lots of foods, especially whole fruits and vegetables. Fruits like berries and citrus are some of the best sources.

Without vitamin C the body would run into a lot of problems. That’s because we need it for:

  • Good immunity
  • Antioxidant activity
  • Less sickness
  • Less inflammation
  • Healthy skin and tissues
  • Supporting healing in the body
Different types of vitamin C | Natural and synthetic vitamin C

That’s right: there’s more than one kind of vitamin C. Which may seem confusing!

Essentially, there are natural vitamin C and synthetic vitamin C. We cannot create natural vitamin C for supplements (unless we include vitamin C-rich whole food ingredients), so a synthetic type is made instead for supplements.

True natural vitamin C is made up of many different bioflavonoids. These bioflavonoids are basically antioxidants with powerful effects that enhance each other’s properties when taken together.

Synthetic vitamin C, on the other hand, has many different names and types that you’ll find on labels and ingredient sections. Beside ascorbic acid which is commonly found in supplements, beverages & packaged foods, other forms of synthetic vitamin C you’ll find on labels are salts of vitamin C such as:

  • Calcium ascorbate
  • Sodium ascorbate

You’ll find later in this article why we don’t recommend any types of synthetic vitamin C including salts of vitamin C.

What is ascorbic acid?

Unlike natural vitamin C, ascorbic acid is man made in a laboratory. It comes in a powder-like substance so it can be easily added to foods or made into supplements.

While it’s created to supplement your body if you’re not getting enough, it’s not chemically exactly the same as natural vitamin C found in whole foods— though it is extremely similar.

Regardless, ascorbic acid definitely isn’t absorbed by your body in the same way as natural whole food vitamin C sources! And as it turns out, it also doesn’t do all that natural vitamin C can do for you, either…and can even be more harmful than good for your health.

The dangers of too much ascorbic acid

Unlike natural forms of vitamin C, ascorbic acid can have nasty side effects. These include:

  • Nausea
  • Vomiting
  • Heartburn
  • Abdominal cramping
  • Digestive upset
  • Diarrhea
  • Dizziness
  • Fainting
  • Headaches
  • Sleeplessness
  • Gout
  • Increased risk of kidney stones

All these can happen when too much ascorbic acid is taken, which happens more easily than you’d think. This is called “megadosing” (taking greater than 2000 mg daily) and has been misleadingly recommended by some health experts as if it is healthy.

So much ascorbic acid gets added as extra to foods, supplements, juices, smoothies, and beverages, that you could even megadose by mistake! Some people are also tempted to “megadose” for beating a cold or getting over a hangover.

Some may also eat so much processed food and junk that they think megadosing is a great way to make up for it! But you can’t get around it: nothing is better than natural vitamin C whole food or herbal extract sources.

On the other hand, it’s very hard to eat too much vitamin C from natural sources. There haven’t been many examples of anyone at all experiencing vitamin C sensitivity from natural food sources (especially considering that we all need it to survive).

But even then, there are actually no studies showing megadoses are healthier for those who are already healthy and well-nourished anyway (even with natural vitamin C).

There are even signs that excessive vitamin C “reverses” its effects, transforming it from an antioxidant into something closer to an inflammation and cancer-causing free radical!

Research has also shown 500 mg every day can increase hardening of the arteries. In athletes, 1000 mg of ascorbic acid per day had a very negative effect on oxygenation and their endurance capacity.

These doses are not in the unhealthy range for our vitamin C requirements at all! So what does this say about ascorbic acid? It’s not good for you.

Some expert sources also claim most ascorbic acid on the market is made from GMO corn; or that it can impact how we get nutrients (like copper) from other foods.

Would megadosing with vitamin C or ascorbic acid even work?

There are different suggestions from health experts up to what dosage of vitamin c is safe. This opinion ranges from 500 to 3000mg per day based on different studies.

Besides the health harms and side effects, another issue is that high amounts of vitamin C of any kind aren’t completely absorbed by your body, anyway! (Especially if you are already fine and healthy.)

It’s true even if the labels say there are thousands of milligrams of Vitamin C in the food or supplement you’re eating, experts agree on the fact vitamin C in doses higher than 200mg is a lot less effective or easily absorbed in one dose, such as from a supplement containing ascorbic acid (not to mention the negative health effects!). As such several smaller doses of vitamin C each day is preferable to a single higher dose if you’re aiming to take higher doses of Vitamin C.

That said, the only time where anything close to “megadosing” of ascorbic acid would be recommended as healthy, is for the very, very ill and intravenously, such as in a hospital (though this is still usually done with ascorbic acid made from GMO corn).

How are natural vitamin C and ascorbic acid different in bioavailability?

Some claim that ascorbic acid is more bioavailable (easily absorbed) than natural vitamin C, while others claim that natural vitamin C actually works better in this way.

The fact of the matter is: both are equally bioavailable! According to research, however, whole food sources contain other nutrients that boost natural vitamin C’s availability too: such as fiber, minerals, and other vitamins.

Overall, studies also show people benefit better from natural whole food vitamin C sources than ascorbic acid. Unfortunately, seeing the importance of whole food sources of nutrients is something the supplement and pharmaceutical industries overlook.

An example: curcumin is often extracted from the herbal remedy turmeric into supplements for numerous health benefits (such as inflammation, depression, and more).

This is because scientists have found curcumin to be one of the most active and effective ingredients in this herbal spice. But is it the only active ingredient?

A few studies have suggested that turmeric is actually more effective than curcumin! It’s because there are many different active phytochemicals and curcuminoids that enhance one another’s properties, instead of just one. (Herbalists have known this for hundreds of years and today refer to this as “synergistic action.”)

It’s the same with ascorbic acid. Ascorbic Acid is only one part of Vitamin C. Vitamin C has other vitamins, minerals and flavonoids beside ascorbic acid. When it’s separated from other natural compounds and natural foods, it just doesn’t have the same benefits, even if it is more bioavailable or chemically similar. In this case ascorbic acid is not even taken from natural sources rather made synthetically often from GMO corn using solvents like acetone.

Vitamins (especially ascorbic acid) cannot simply be isolated from their complexes and still be expected to have the same functions!

Is one really more effective than the other?

That said, the effectiveness of natural vitamin C vs. ascorbic acid has been explored quite a bit already.

On the one hand, there are tons of studies showing that whole fruits and vegetables lower disease risks like heart disease, stroke, cancer, and more; a lot of this is attributed to the natural vitamin C in these foods.

The same cannot be said for ascorbic acid or man made vitamin C supplements, however! Especially with heart disease, the evidence is strong: whole fruits and vegetables (rich in natural vitamin C) have time and time again been linked to a lower risk.

Can the same be said for supplement vitamin C, like ascorbic acid? Not so much, and even scientists will say so.

What products contain ascorbic acid?

Some of the most common ascorbic acid-containing products are:

  • Most vitamin C supplements
  • Vitamin complex supplements (with multiple vitamins and minerals)
  • Pre-packaged smoothies and juices
  • Vitamin C packets (like Emergen-C)
  • Pre-packaged or processed fruit products (like fruit leather, fruit snacks, jams, jellies, preserves, candies, cough drops, etc.)
  • Cured meats
  • Fortified foods (cereal, breads, etc.)
How do I avoid ascorbic acid? | Where it’s hidden and how to read labels

The first step for avoiding ascorbic acid is easy. Look for it on ingredient labels before you buy or eat— it’s that simple!

Be careful though, because ascorbic can be hidden in things or disguised as other ingredients. Especially if ingredient labels just state “vitamin C,” this probably means the vitamin C was added synthetically as ascorbic acid.

Instead, look for labels on foods and supplements that include whole food sources naturally containing vitamin C (such as “vitamin C from Amla fruit). The labels might state this outright, especially on supplements. Otherwise, look for whole food ingredients rich in vitamin C like oranges, citrus, strawberries, spinach, broccoli, rosehips.


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