Sources of Vitamin C

The richest vitamin C sources are fresh vegetables and fruit: rosehip, red and green peppers, kiwi, strawberries, citrus fruits such as oranges, broccoli, Brussels sprouts and parsley top the list. Your body cannot make vitamin C or store it for long, so you need to get it from food every day. A healthy adult who eats a varied diet can usually meet their needs without a supplement.

What is vitamin C and what does it do in the body?

Vitamin C (ascorbic acid) is a water-soluble vitamin involved in many of the body’s basic functions. Because it dissolves in water, any excess is passed in the urine; it does not build up in the body the way fat-soluble vitamins do. Its main roles are:

• Collagen production: It is needed to make collagen, the building block of skin, cartilage, bone, blood vessel walls and gums, which is why it also matters for wound healing. We cover this in detail in our article on collagen and collagen supplements.
• Antioxidant action: It helps protect cells against oxidative damage caused by free radicals.
• Iron absorption: It increases the absorption of iron from plant sources such as legumes and leafy greens.
• Immunity: It contributes to the normal function of the immune system.

Which foods contain the most vitamin C?

The richest sources of vitamin C are fresh vegetables and fruit that can be eaten raw or only briefly cooked. Oranges may be the first thing that comes to mind, but they are not the only option; many vegetables contain at least as much vitamin C.

Fruit

• Rosehip: One of the fruits highest in vitamin C, although drying and long boiling reduce its content considerably.
• Kiwi and strawberries: Even a small portion makes a real contribution, and they are an easy snack.
• Citrus fruits: Oranges, mandarins, grapefruit and lemons. One medium orange can cover a large part of an adult’s daily needs.
• Other fruit: Melon, pineapple, mango and blackberries are also good sources.

Vegetables

• Peppers: Red, yellow and green peppers; ripe red peppers are especially rich. Eating them raw keeps vitamin loss to a minimum.
• Cruciferous vegetables: Broccoli, Brussels sprouts, cauliflower and white or red cabbage.
• Leafy greens: Parsley, rocket, cress, spinach and purslane. Adding plenty of greens to salads is an easy way to boost your intake.
• Tomatoes and potatoes: Neither is especially high on its own, but because we eat them often they make a meaningful contribution to daily intake.

How much vitamin C do you need per day?

For healthy adults, the daily requirement for vitamin C is generally given as 75–90 mg; reference values vary between countries and with age and sex. Someone who eats at least five portions of vegetables and fruit in different colours every day will usually meet this easily.

Needs increase in certain situations:

• Pregnancy and breastfeeding
• Smoking (smokers need more vitamin C)
• Feverish illness, recovery from surgery and wound healing
• A very restrictive or monotonous diet

Children’s needs vary with age. During pregnancy, breastfeeding and childhood, always talk to your doctor before taking a supplement.

How can you preserve vitamin C when cooking?

Vitamin C is sensitive to heat, air, light and water, so the way food is prepared and cooked directly affects how much of it remains. When vegetables are boiled for a long time in plenty of water, the vitamin leaches into the cooking water, and if that water is poured away, a large share of it is lost. Leaving cut or cooked vegetables and fruit to stand also increases losses. These simple steps make a difference:

• Trim and chop vegetables just before cooking, and do not leave them standing once cut.
• Steam them, cook them in a little water or sauté them briefly instead of boiling in lots of water.
• Add vegetables to water that is already boiling rather than cold water, and keep cooking times short.
• If you do boil them, use the cooking water in a soup or sauce.
• Add lemon juice and fresh herbs at the moment of serving.
• Drink freshly squeezed juice straight away, although eating the whole fruit is still the better choice because of its fibre.
• Store vegetables and fruit somewhere cool and dark or in the fridge, and do not keep them for too long.

Does vitamin C boost immunity?

Vitamin C is essential for the immune system to work normally, but taking more than you need does not give you extra protection against illness. Research shows that regular vitamin C supplements do not noticeably reduce the risk of catching a cold in the general population, and their effect on how long a cold lasts is limited. What really protects you in winter is enough sleep, regular activity, good hand hygiene and a balanced diet that includes vegetables and fruit every day. For the general principles, see our healthy eating guide.

Intravenous vitamin treatments (IV therapy) should only be planned after a medical assessment and when they are judged necessary; they do not replace a balanced diet.

How does vitamin C affect iron absorption?

Vitamin C helps your body absorb the iron in plant foods more efficiently. That is why eating iron-containing foods together with a source of vitamin C at the same meal is a smart habit:

• A lemony salad with plenty of greens alongside lentils, chickpeas or a white bean stew
• Tomatoes, peppers and parsley with your eggs at breakfast
• A squeeze of lemon over spinach or chard just before serving
• A kiwi or a few strawberries with dried apricots or hazelnuts as a snack

Because tea and coffee can reduce iron absorption, it is best to drink them some time after an iron-rich meal rather than with it. We cover this in detail in our article on iron deficiency and nutrition.

Do you need a vitamin C supplement?

Most healthy adults who eat a varied diet do not need a vitamin C supplement. A supplement may be considered for people on a very restrictive diet, those with absorption problems in the digestive system, or when a doctor has found a deficiency. Extra vitamin C from food rarely causes problems, but high-dose supplements can cause stomach upset and diarrhoea and may raise the risk of kidney stones in people who are prone to them. So talk to your doctor or dietitian before deciding to take one.

At our clinic in Etiler, our dietitian Berna Melis Hepgüler can review your current eating habits and put together a plan that helps you get vitamin C and other vitamins and minerals from natural food sources.

When should you see a doctor?

Severe vitamin C deficiency is rare today, but it can occur in people who go a long time without eating vegetables and fruit, follow a very restrictive diet or have absorption problems. It is a good idea to see a doctor if you notice:

• Bleeding gums, easy bruising or wounds that are slow to heal
• Unexplained, long-lasting tiredness, weakness or joint pain
• You are considering a supplement and have a history of kidney stones, kidney disease or an iron overload disorder (haemochromatosis)
• You take regular medication, are pregnant or breastfeeding and want to take a supplement

These signs can also point to other health problems, so a proper diagnosis requires an examination and, if needed, a blood test.

Frequently asked questions

Which fruit has the most vitamin C?

Among commonly eaten fruits, rosehip, kiwi, strawberries and citrus fruits are some of the richest sources. Oranges are not the only option; vegetables such as red peppers and broccoli contain at least as much vitamin C. Eating vegetables and fruit in different colours every day is the most reliable approach.

Is too much vitamin C harmful?

Excess vitamin C from food is usually passed in the urine and does not cause problems. High-dose supplements, however, can cause stomach upset and diarrhoea and may pose a risk for people prone to kidney stones. It is best to take a supplement only after talking to your doctor.

Does rosehip tea cover your vitamin C needs?

Rosehip fruit is very rich in vitamin C, but a large part of the vitamin can be lost during drying and long brewing. Rosehip tea can be a pleasant extra, but fresh vegetables and fruit should remain your main source.

Do frozen vegetables and fruit still contain vitamin C?

Vegetables and fruit frozen soon after harvest retain most of their vitamin C. They can be a good alternative to fresh produce that has been stored for a long time. Cooking them from frozen, briefly and in a little water, keeps losses down.

Should you drink lemon water on an empty stomach in the morning?

Lemon water adds a little to your daily vitamin C intake and can make it easier to drink enough water. There is no proven special benefit to drinking it on an empty stomach, and it can cause heartburn in people with a sensitive stomach or reflux. What matters is eating enough vegetables and fruit over the day.

This content is for information only and does not replace a medical examination. For a nutrition plan tailored to you, get in touch with us.