Vitamin C, one of the essential nutrients required by the human body, is a key component for numerous aspects such as healthy immune function and neurotransmitter production. It also functions as a powerful antioxidant in the body.
Whether you are a fitness enthusiast or someone who falls sick often, knowing the richest sources of vitamin C and the benefits of consuming this essential vitamin can be beneficial. Keep reading to learn more about vitamin C (including its function in the body, recommended dietary allowance, and things affecting its absorption in the body) or skip ahead to the list of vitamin C fruits/foods list to find the best sources of this vitamin.
Vitamin C: Overview
Vitamin C, also known as L-ascorbic acid, is a water-soluble vitamin that is one of the essential micronutrients the human body requires to maintain good health. Humans cannot produce vitamin C on their own as certain animals do; thus, they need to consume it regularly in adequate quantities to replenish vitamin C supply in the body.
Vitamin C helps with the growth and proper functioning of various body parts as well as the production of important compounds (e.g., collagen, L-carnitine, and neurotransmitters). Vitamin C deficiency can affect a person’s heart, brain, muscle, nerve health, energy levels. Vitamin C also prevents cell damage that can lead to various diseases by restoring the level of antioxidants in the body. It is also important in a number of metabolic functions including the following:
- Activation of vitamin B and folic acid
- Conversion of cholesterol to bile acids
- Conversion of tryptophan (an amino acid) to serotonin (neurotransmitter)
- Absorption of iron
- Metabolising protein
Additionally, vitamin C offers the following health benefits:
- Immunity function by helping the body in producing white blood cells to fight against an infection/disease
- Heals wounds by assisting in the biosynthesis (production) of collagen, which is an essential component of connective tissue
- Bones, teeth, and cartilage repair and maintenance
- Reduces the severity of allergic reactions
Numerous naturally occurring vitamin C rich foods are available in the market, but this vitamin can also be added to a person’s diet in the form of synthetic supplements. Moreover, eating excess quantities of vitamin C in a short duration may not have any adverse effects since it is water soluble and passes out the body through urine; however, consuming excess vitamin C over a long period of time may lead to vitamin C toxicity.
Including vitamin C foods in your diet
All plant species can produce vitamin C, which is why most of our daily intake of vitamin C comes from a plant-based diet. There aren’t many animal sources that are rich in vitamin C, apart from livestock livers and certain fish eggs. Additionally, fungi can also synthesise and are a good source of vitamin C. People generally get their daily recommended dose of vitamin C from fruits and fruit juices. Mentioned below are some of the richest sources of vitamin C.
Vitamin C fruits list:
- Indian gooseberry
- Star fruit
- Bell peppers
- Chilli peppers
Vitamin C vegetables list:
- Brussels sprouts
- Mustard spinach
- White potatoes
- Red/purple cabbage
Note that potatoes are not a rich source of vitamin C but since they are consumed in large quantities, they make a suitable vitamin C source.
All citrus foods contain a sufficient amount of vitamin C, which is comparable to vitamin C quantities seen in some of its richest sources.
Beverages prepared with vitamin C rich fruits and vegetables mentioned above are also an excellent source of vitamin C and can fulfil the daily necessary requirement of the vitamin.
Other vitamin C rich foods:
- Herbs like coriander and parsley
- Animal liver and kidney
Did you know sea buckthorn and rose hip are one of the richest sources of vitamin C found in India? They generally grow in colder regions in the northernmost parts of India. Additionally, West Indian cherry (also known as Barbados cherry), which is native to West Indies and southern Texas, is the richest known source of natural vitamin C.
Daily recommended amount
The recommended dietary allowance or RDA for women who are 19 years or older is 75 mg/day, and for men of the same age, this value is 90 mg/day. Pregnant women need more than usual amount (about 85–120 mg/day) of vitamin C in their diet. People who smoke need an additional 35 mg/day in their diet as smoking depletes vitamin C levels in the body.
Note that 2000 mg/day is the tolerable upper intake level; consuming vitamin C beyond this amount may lead to gastrointestinal distress and diarrhoea. Consuming such a high dosage of vitamin C is recommended only under medical supervision for specific cases or in controlled clinical trials. One should never consume vitamin C beyond the recommended RDA unless ordered by a physician.
Absorption of the vitamin C
The intestine can only absorb a limited amount of vitamin C and taking excessively high dosage of the vitamin may not improve a person’s vitamin C levels. The body excretes excess vitamin C once the tissues become saturated through urine. The absorption of vitamin C does not vary with the consumption of natural sources of vitamin C or its supplements. In some cases, a doctor may also administer vitamin C intravenously to an individual so that a significant amount of the vitamin can enter the person’s bloodstream.
Preserving vitamin C in the foods
Cooking and boiling foods with vitamin C for a long duration with a large amount of water can decrease the vitamin C content in an item. This is because vitamin C is water soluble and can decompose from oxidising agents, high temperature, high pH, and metal ions. Blanching vegetables and fruits also leads to a considerable loss of the vitamin C content in the said food item. Thus, eating fresh or raw vitamin C rich foods is preferred when someone is trying to increase their daily intake of the vitamin without any additional supplements. If you don’t want to consume vitamin C rich foods raw or in a salad, you can consider frying the food item as this method of cooking retains sufficient amount of the vitamin.
Storing vitamin C rich foods at lower temperatures is recommended to make them last long, but consuming them soon is preferred as the vitamin C content in the food item reduces with over time. This is because these food items contain an enzyme—ascorbic acid oxidase—that can oxidise and decompose vitamin C, and storage at low temperature (deep freezing) is effective in inactivating the enzyme.
Vitamin C deficiency
If a person consumes a nutrition-deficit diet that provides less than 10 mg/day of vitamin C for about a month or longer, they may develop a vitamin C deficiency. Avoiding fruits and vegetables, smoking, long-term passive smoking, and alcohol and drug abuse are some factors that can lead to a vitamin C deficiency. People who have a vitamin C deficiency are prone to getting scurvy and display symptoms like bleeding/bruising from broken blood vessels, swelling/bleeding of gums, hair loss, and delayed healing of skin wounds. Additionally, vitamin C deficiency can cause iron-deficiency anaemia and the following symptoms:
- Excessive fatigue
- Feelings of sadness and irritability
- Easily bruising skin
- Severe joint or leg pain
Vitamin C toxicity
Although the body excretes excess amounts of vitamin C through urine, you can develop vitamin C toxicity if you consume abnormally high amounts of vitamin C rich foods and/or supplements over a long period of time. An excessive consumption of vitamin C may lead to digestive issues and stomach pain. It may also affect the interaction of certain medications in the body.
It is extremely important to check with a doctor before starting a supplement and consuming higher than UL of vitamin C to avoid any complications.
The bottom line
Vitamin C is essential in leading a healthy life as it plays a vital role in the body. Consuming a diet deficient in vitamin C can negatively impact your health, so does consuming an excessively high amount. Including the vitamin C rich fruits and vegetables mentioned here in your diet can have a positive impact on your health. People who have allergies and fall sick frequently must consider increasing their daily intake of vitamin C rich foods to aid their immune system. If you are struggling with bad health or are confused about planning a proper diet/which supplement to take, consider consulting a doctor and get a health check-up.