Vitamin C, or ascorbic acid, is a water-soluble vitamin. This means that it dissolves in water and is delivered to the body’s tissues but is not well stored, so it must be taken daily through food or supplements. 
Vitamin C plays a role in controlling infections, and healing wounds, and is a powerful antioxidant that can neutralize harmful free radicals.
It is needed to make collagen, a fibrous protein in connective tissue that is weaved throughout various systems in the body: nervous, immune, bone, cartilage, blood, and others.
The vitamin helps make several hormones and chemical messengers used in the brain and nerves. 
In Australia, it is recommended that adults have 45mg of vitamin c every day. That equates to half an orange or a cup of strawberries. Some people, like smokers or people who are breastfeeding, may need more.
If you are worried about your vitamin C, keep a food diary and show it to your GP or dietician.
Many people think that high doses of vitamin C can be helpful against chronic illness.
However, too much vitamin C causes nausea, abdominal cramps, headaches, fatigue, kidney stones and diarrhoea.
Too much vitamin C can also interfere with the way your body absorbs other essential nutrients, such as iron.
Eating healthy food that contains vitamin C is the best way to make sure you are getting the right amount. If you are taking vitamin supplements, it is recommended  that you don’t exceed 1000mg.
Most people think that Vitamin C will boost their immune system and prevent them from becoming ill.
While much of the research that investigates this idea is mixed, there is a growing consensus among researchers that vitamin C shortens the duration of the common cold but does not reduce the risk of becoming ill.
Taking supplements once cold symptoms have already begun has no proven benefits.
In summary, including fruit and vegetables every day in your diet will help you get enough vitamin C. If you aren’t sure, consult your doctor, nutritionist or dietician.
Vitamin C is found in many fruits and vegetables.
Fruits include citrus fruits such as oranges, grapefruit and lemon, kiwi fruit, blackcurrants, strawberries and guava.
Vegetables, including broccoli, cauliflower, cabbage, cooked kale, Brussels sprouts and Chinese cabbage.
The amount of vitamin C in fruits and vegetables varies and can be influenced by season, transportation, shelf life and storage time.
Eating fresh fruit and vegetables is ideal because cutting, bruising, cooking, heating or exposing food to certain materials can destroy vitamin C.
To boost your intake, try adding a fruit or vegetable that’s high in vitamin C to some of your meals, or having an orange as a snack. 
1. Vitamin C | The Nutrition Source | Harvard T.H. Chan School of Public Health
2. Vitamin C and your health | healthdirect
3. Vitamin C | Linus Pauling Institute | Oregon State University