How Much Vitamin C Do You Need?

Vitamin C - also called L-ascorbic acid or just ascorbic acid - is absolutely essential for our bodies to function normally. But we didn't always need it...

All mammals have a gene that produces Vitamin C. But in humans and apes, this gene is completely deactivated through genetic errors.

The reason is believed to be this: our ancestors, before we became apes, were rat-like animals. Probably something like this (image credit: Mark Witton/University of Portsmouth)...

These creatures needed the Vitamin-C-production gene to protect themselves from free radicals. When they evolved into early apes, who lived in trees and ate tons of fruit, suddenly they got so much Vitamin C through their diet that they didn't need to produce it anymore!

In nature, what isn't needed is lost, since individuals who lose these traits don’t have an evolutionary disadvantage. So the Vitamin-C-producing gene was eventually deactivated in apes.

Then we came down from the trees to the African Savanna, changed our diet away from fruits... and suddenly we were in need of Vitamin C, without an active gene to support us.

The all-in-one vitamin

The list of Vitamin C benefits is immense, and includes helping boost your skin’s collagen production, which helps repair damaged skin; decreasing the risk of dry skin; boosting with Iron intake and regenerating Vitamin E; maintaining normal mental function, a normal immune system, and a normal nervous system; and it has even been linked to an improved mood.

As we learned above, we need to get our Vitamin C externally. There are plenty ways to do this - from citrus fruits to nutrient microbeads.

But if you try Googling the recommended dosage you’ll be flooded with a huge array of credible sources telling you to take different amounts of Vitamin C. These reports are based on lengthy studies involving hundreds or even thousands of participants.

In other words, they’re not personalized for you in particular - they are considering large groups of the population.

Does your diet contain enough Vitamin C? Do you have genetic variations that alter your nutrient needs? Does prolonged UV exposure and pollution in your area affect your vitamin and mineral requirements?

These are all questions we take into consideration at Rootine. We factor in your lifestyle (including diet and environment), genetic variations and nutrient blood levels to figure out exactly how much Vitamin C you need.

Let’s dive further into the benefits of Vitamin C.

What are the benefits of taking Vitamin C?

Vitamin C is a bit of an all-in-one Vitamin. It acts as an antioxidant, which means it helps fight off free radicals - harmful molecules that are formed when our bodies convert food into energy (a normal metabolic function), which can damage cells and lead to cancer, heart disease, Parkinson’s and a number of other serious diseases.   

Vitamin C is also a necessary component in the production of collagen, which, besides improving skin health, also strengthens your bones and maintains healthy hair, among other benefits (ex. healthy teeth, blood vessels, gums).

Vitamin C has even been shown to increase intimacy and improve mood!

Something we always hear in media and from supplement companies is how Vitamin C helps fight colds. Along with Zinc, Vitamin C does help support our immune system; it also helps reduce cold symptoms and cold duration, but has not been proven to lower the frequency of colds in a study involving over 11,000 participants.

In a nutshell, Vitamin C is essential for a healthy body and mind, and has a huge list of benefits. But what happens if we take too little, or too much?

What happens if you’re deficient in Vitamin C?

Vitamin C deficiency isn’t common in the US or other developed countries. The most notorious side effect of too little Vitamin C intake is scurvy, which has been reported as far back as 1550 BC by Hippocrates (the ancient Greek physician widely known as the father of medicine - follow the link for his rather grim description of scurvy in ancient Greece).

In the 1700s, British Royal Navy doctor James Lind discovered that citrus fruits helped mitigate scurvy. In 1927, Vitamin C’s structure was discovered, and since then we’ve had abundant access to the Vitamin - and very little scurvy.

In the US, we get a lot of our Vitamin C from juices, as well as citrus fruits and veggies. You’d have to try pretty hard to get to less than 10mg a day for over a month, which the Harvard T.H. Chan School of Public Health cites as “deficient”.

Nevertheless, external factors like pollution and UV exposure, as well as internal genetic factors might influence your Vitamin C dosage requirements. This is why we recommend factoring in lifestyle, genetic information and blood levels to properly assess your nutrient requirements. While some people might need less than a 100mg of Vitamin C daily, you may require a different dosage.

What if you take too much Vitamin C?

In the 70s, two-time Nobel prize winner Linus Pauling popularized the notion of megadosing Vitamin C as a dietary supplement, effectively starting the trend. In subsequent decades, researchers found little benefit of ingesting several grams of Vitamin C.

That’s because the body tightly controls how much Vitamin C actually gets absorbed: about 70-90% gets absorbed when you take 30-180mg per day, and less than 50% if you’re taking doses above 1,000mg. The excess Vitamin C (literally) just goes down the toilet.

So how much Vitamin C should you be taking? Over the decades, researchers have recommended varying dosages, but you might be surprised to hear these numbers are much lower than what we see in OTC Vitamin C supplements.

The US Office of Dietary Supplements suggests 75mg for women and 90mg for men, per day. For women who are pregnant or lactating, the Office suggest 85mg and 120mg, respectively. They also cite a maximum daily intake of 2,000mg.

Unfortunately, for every definitive dosage you find online, you will surface a number of contradictory sources, including studies that completely invalidate seemingly legitimate findings. This is far from ideal when you’re deciding how much Vitamin C you should be taking. As we’ve mentioned, the best way to find your exact requirements is to consider lifestyle and genetic factors, as well as measure nutrient blood levels.

What foods have Vitamin C?

The most well-known sources of Vitamin C are citrus fruits, like oranges, kiwis, lemons and grapefruits. Veggies like bell peppers and tomatoes are good sources, as is broccoli, Brussels sprouts, cauliflower and potatoes. Check out My Food Data’s excellent printable list for exact values per Vitamin-C-rich food.

There are some foods that are seriously brimming with Vitamin C from the list above:

  1. Acerola Cherry: 1864% Daily Value (DV) (1,678mg) in 100 grams
  2. Rose Hips: 473% DV (426mg) in 100 grams
  3. Guavas: 254% DV (228mg) in 100 grams
  4. Sweet Yellow Peppers: 204% DV (184mg) in 100 grams
  5. Black Currants: 201% DV (181mg) in 100 grams

Get personalized nutrients delivered to your door

Our personalized nutrient packets include Vitamin C and up to 17 other vital nutrients - all dosed according to DNA kit results and lifestyle assessment. To see what's included in your monthly subscription of Rootine vitamins and minerals, see the link below.

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