Your Body Doesn't Store a Single Drop: How to Tell If You're Running Low on Vitamin C

You brush your teeth and the sink turns pink. A bruise appears on your shin and you have no idea where it came from. Your cold has dragged on for two weeks, and you feel tired before lunch. Each of these on its own may mean nothing. Together, they may be your body quietly telling you that one of its most basic nutrients is running low. Unlike most animals, we cannot make vitamin C ourselves, and we cannot save it for later either. What you ate yesterday is already largely gone today.

The Nobel Laureate Who Swore by Vitamin C

Few people have been as passionate about vitamin C as Linus Pauling, the only person ever awarded two unshared Nobel Prizes. In a recorded talk preserved by Oregon State University, he described how a fellow researcher suggested he take three grams of vitamin C a day. Pauling and his wife both started doing so, and he said they no longer suffered from colds the way they had before. The experience inspired his famous book Vitamin C and the Common Cold, which made the vitamin a household name.

Science has since tempered some of Pauling's bolder ideas. Even the Linus Pauling Institute at Oregon State University, founded in his name, notes that he based his recommendations largely on theoretical arguments. Today it suggests around 400 mg a day for healthy adults, an amount that is reachable with food alone. His core message still holds, though: vitamin C is something your body needs every single day.

Why Your Body Can't Stock Up

Vitamin C, or ascorbic acid, is a vitamin that our body can neither produce nor store. The body therefore cannot build up a reserve, and a varied diet is the only way to get enough of it.

In addition, vitamin C is water-soluble, so any excess leaves the body through urine and sweat. This also means it doesn't help much if we eat vitamin-rich food in the morning and then nothing more for the rest of the day, because the surplus will quickly leave the body. Vitamin C is something we need to take care of every day and at every meal.

How much do you need? According to the U.S. National Institutes of Health (NIH), the recommended daily amount for adults is 75 mg for women and 90 mg for men. Smokers need an extra 35 mg a day, because smoking increases the body's use of vitamin C. Pregnant and breastfeeding women also need a little more.

Everyday Signs That Your Intake May Be Low

Common signs that may point to low vitamin C intake include:

• Gums that bleed easily: vitamin C helps the body make collagen, which supports healthy gums and blood vessel walls.


• Bruises that appear for no obvious reason: when the small blood vessels under the skin are more fragile, even a light bump can leave a mark.


• Tiredness and low energy: fatigue is often one of the first and most easily overlooked signs.


• Small cuts and scrapes that heal slowly: wound healing depends on collagen, and collagen depends on vitamin C.

These are subtle, everyday signals, and many other things can cause them as well. If your intake stays low over a longer period, the signs can become more noticeable.

• Dry hair and split ends: among other things, vitamin C supports healthy hair, and even more so healthy skin. A shortage may contribute to split ends and dry skin. Dry skin is a particular nuisance during the heating season, when indoor air is already very dry.



• Colds that seem to keep coming back: if you feel like colds keep catching up with you and you can't quite shake them, low vitamin C may be one piece of the puzzle. A large Cochrane review found that regular vitamin C intake did not lower the number of colds in the general population, but it was linked to colds that lasted somewhat less long. Just as important: give yourself a few days of real rest. Colds, flu, a lingering cough and a runny nose can sometimes be the tail end of a previous illness you never fully recovered from.



• Weight that seems harder to manage: vitamin C helps the body make carnitine, a compound involved in using fat for energy. In a small preliminary study published in Nutrition & Metabolism, researchers at Arizona State University found that people with marginal vitamin C levels burned about 25% less fat during a one-hour treadmill walk than people with adequate levels. This does not make vitamin C a weight-loss tool, but it is one more reason not to neglect it.

A severe and prolonged lack of vitamin C leads to scurvy. Many people consider it a disease of old sailing ships, but according to the NHS it still occurs today, mostly in people whose diets contain very little fresh fruit and vegetables. If you notice several of the signs described here, the sensible step is to talk to your doctor, who can check whether something else is behind them.

A Reader's Story

One of our readers, a busy office worker in her forties, told us she spent an entire winter "living on coffee and sandwiches." By February her gums bled every time she brushed, and she had bruises on her legs she couldn't explain. Her dentist asked about her diet and suggested she start adding fruit and vegetables to every meal. "I started with a kiwi at breakfast and peppers in my lunch salad," she says. "Within a few weeks I noticed the difference, and I haven't gone back to my old habits since." Her experience is a good reminder that small, steady changes often matter more than big resolutions.

Where to Find Vitamin C, and How to Keep It

The good news is that vitamin C is easy to find. Citrus fruits are the classic choice, but peppers, kiwi, strawberries, broccoli, Brussels sprouts and dark leafy greens are excellent sources too. A single large red pepper can cover more than a full day's needs. Kiwi is another star: as we explained in 3 fruits that help you lose weight, 100 g of kiwi provides more than the daily requirement of vitamin C, along with plenty of fiber.

How you prepare and store your food matters just as much. Vitamin C is sensitive to heat, light and oxygen. Broccoli keeps most of its value when eaten raw or steamed briefly, and strawberries should be stored in a cool, dark place and eaten soon. You'll find more practical tips in Foods We Use Incorrectly. Even blending can reduce vitamin C if the blender heats the ingredients, which is why we suggest adding ice cubes in our recipe for Summer flu due to air conditioning? 3 ingredients that strengthen the immune system.

Vitamin C also works as a team player. It helps the body absorb iron from plant foods such as spinach, lentils and beans. Learn how to make the most of these pairings in Foods That Improve Nutrient Absorption.

Simple Ways to Spread Vitamin C Across Your Day

• Breakfast: add berries or sliced kiwi to your yogurt or oatmeal, or enjoy an orange alongside your meal.


• Lunch: include raw peppers, tomatoes or a handful of leafy greens in your salad or sandwich.


• Snacks: reach for fresh fruit or crunchy vegetable sticks instead of packaged snacks.


• Dinner: serve briefly steamed broccoli or Brussels sprouts and add a squeeze of lemon juice at the end of cooking.

Can You Have Too Much?

Because the body flushes out what it doesn't need, getting too much vitamin C from food is very unlikely. Supplements are a different story. The NIH sets the upper limit for adults at 2,000 mg a day. Above that, some people may experience stomach upset, cramps or diarrhea. People with a history of kidney stones or certain iron storage conditions should talk to their doctor before taking high-dose supplements. For most of us, the best strategy is simple: a colorful plate, several times a day, every day.