Vitamin C In Kiwi For Immunity

Introduction

What is immunity? 

Immunity refers to your body's ability to resist and defend itself against potentially harmful microorganisms, including bacteria, viruses, parasites, etc. The immune system is a complex network of cells, tissues, and organs that work together to identify and eliminate foreign bodies while differentiating the body's healthy cells. Your immune system is responsible for protecting your body from infections and diseases. So, the better your immunity, the less likely you are to fall sick, have intense symptoms, and take a longer time to get better. 

The immune system can have two main types of responses:

• Innate Immunity: It is your body's first line of defence and provides immediate, nonspecific protection against a wide range of pathogens. It includes physical barriers (like the skin), chemical barriers (such as stomach acid), and various cells that can quickly respond to foreign substances.
• Adaptive Immunity: It is also called acquired or specific immunity since it develops over time when your body is exposed to different pathogens. It identifies pathogens and is able to target and fight them off on exposure. 

Having a good immunity that functions well and fights off diseases is the key to maintaining your health and avoiding frequent infections. You can build a strong immunity for yourself by ensuring you have a balanced diet, regular exercise, and adequate rest. Vaccinations can also be a crucial means to strengthen your immunity against specific infections. 

In this article, we will talk about how you can incorporate a natural immune booster, the fuzzy and fresh kiwi fruit into your diet. As a source of vitamin C, which is a great antioxidant, kiwi fruits can offer quite a few benefits to your immune system. Let’s look into some of them!

Introduction to Vitamin C as a key nutrient for immune health.

Vitamin C, also known as ascorbic acid, is a water-soluble molecule. This means that it can be delivered to your body’s tissues since it dissolves in water and can’t be stored effectively. Vitamin C needs to be taken regularly and adequately through foods or supplements. Also, Vitamin C has  been associated with immune-boosting functions including :

• Reducing the risk of chronic diseases
• Helping the immune system prevent infectious bodies from entering the body
• Reducing the duration and severity of symptoms for common respiratory illnesses such as a common cold

Focus on kiwifruit as a rich source of Vitamin C

Fresh food, specifically fresh fruits, are the best available and most effective sources of vitamin C into your diet. Of all the different fruits that contain vitamin C, kiwis are an exceptional source with among the highest content per serving. There are also multiple types of Kiwis, including golden kiwis (Actinidia chinensis), which have fewer hairs and are more yellow and sweet. Others include two cold-hardy species (A. arguta and A. kolomikta), Chinese egg gooseberry (A. coriacea), red kiwi (A. melanandra), silver vine (A. polygama), and purple kiwi (A. purpurea). All these different species of kiwis exhibit variations in their vitamin C content. Golden kiwifruits contain the highest level of vitamin C followed by green kiwifruits. 

Understanding the immune system

The immune system is your body's formidable defence mechanism that works continuously to safeguard you from potential threats. It comprises a complex network of cells, tissues, and organs, and protects you against harmful invaders like bacteria, viruses, and other pathogens.

Imagine your immune system as an orchestra with different instruments playing in harmony. 

• The first line of defence is the innate immune system — a quick and non-specific response that includes physical barriers (like the skin), chemical defences (like stomach acid) and different types of cells that engulf and neutralise invaders.
• The second line of defence is the adaptive immune system, akin to the orchestra's more refined instruments. It is precise and remembers specific pathogens. T cells and B cells, key players in adaptive immunity, work together to recognise and eliminate threats. B cells produce antibodies,  like personalised missiles designed to target specific invaders, while T cells coordinate and enhance the overall immune response.

How does your immune system protect your body? 

The immune system is on constant patrol, monitoring for signs of trouble. When a pathogen breaches the body's defences, it springs into action and can neutralise the threat, remember it for the future, and leave the body stronger and better prepared to fend off similar attacks.

Beyond infectious agents, the immune system also plays a crucial role in identifying and eliminating abnormal cells, such as cancer cells. Its ability to distinguish between your body’s cells and foreign bodies is key to protecting your overall health. 

How is nutrition linked to your immune system?

Proper nutrition is like providing the best instruments to your immune orchestra. Nutrients, especially vitamins and minerals, are the building blocks essential for the proper functioning of immune cells. Vitamin C, found in fruits like oranges and kiwifruit, supports immune function and helps in the production of antibodies. Vitamin D, obtained from sunlight and certain foods, is crucial for activating immune defences.

A balanced diet, rich in fruits, vegetables, whole grains, and lean proteins, ensures that your immune system has the tools needed to operate optimally. Hydration is equally important, as water helps transport nutrients and supports the proper functioning of immune cells.

Vitamin C and immune support

• Vitamin C is essential for the development and maintenance of cells and tissues in the body. This function is strongly linked to how the skin works, serving as the main barrier that stops infections from getting into the body. Vitamin C boosts the activities of components in the epithelial barrier and speeds up the healing process of wounds.¹
• Adequate and regular intake of Vitamin C can protect you against chronic diseases including cardiovascular diseases, cancers, and cataract formation.²
• The significance of Vitamin C in boosting the immune system, particularly concerning the common cold, is widely acknowledged. While it may not act as a preventative measure for healthy individuals, research suggests that it can potentially shorten the duration of cold symptoms. Furthermore, individuals subjected to physical strain from intense exercise or exposure to cold climates may experience a decreased susceptibility to catching a cold with the supplementation of vitamin C.² 
• Ascorbic acid is involved in the efficient functioning of white blood cells, involved in defending the body against foreign infections. It also improves cognition, and mood, and reduces physical and mental fatigue.³ 

Kiwifruit: A vitamin C powerhouse.

Nutritional profile of kiwifruit.

The two most widely consumed types of kiwis, golden kiwis (A. chinensis) and fuzzy kiwis (A. deliciosa) are excellent sources of vitamin C, along with this, they are also rich in nutrients, including:³ 

• Vitamins like Vitamin E, Vitamin K, Vitamin B5, and Vitamin B6.
• Minerals like calcium, copper, potassium, and trace minerals like manganese, chromium, zinc, and selenium.
• Amino acids like cystine, tryptophan, phenylalanine, threonine, tyrosine, and histidine. 
• Dietary fibres, folate, and antioxidants.

Comparison of vitamin C content in kiwifruit with other fruits.

Kiwis have been given an exceptional label based on the amount of vitamin C present in the food per unit weight and likely serving size by the U.S. Department of Agriculture. The vitamin C content of green and gold kiwifruit is 92.7 and 161.3 mg per 100 g, respectively while the Referenced Intake (RI) for vitamin C for labelling is 80 mg. Moreover, the amounts required for ‘source’ or ‘high’ labels of nutrient content claims qualify the vitamin C levels in kiwifruits to be high.⁴ An analysis of over twenty varieties of kiwis reported an average of 25-205 mg/100 mg of vitamin C content of the fruit, including both ascorbic acid (AA) and dehydroascorbic acid (DHAA), which is its oxidised form.² The vitamin C content in kiwifruits is among the highest in any other naturally occurring fruit source. The SunGold kiwifruit contains 161.3 mg of vitamin C per 100 g — almost three times the amount found in oranges and strawberries on an edible flesh weight basis.⁴

Accessibility and incorporation of kiwifruit in a balanced diet

Kiwis, though native to southwestern parts of China, are produced all over the world including countries like Spain and New Zealand among others. The availability of kiwis all year round is possible since the crops are produced and harvested at different times in different parts of the world. Moreover, studies show that though vitamin C content often decreases on storage, levels remain stable in kiwifruits during postharvest ripening.² You can incorporate kiwis into your diet not only as fresh-cut fruit, but also through juices, salads, sorbets, and also cook them.  

Considerations and precautions

Kiwi fruits are among the richest sources of vitamin C, as well as provide your body with many other nutritional benefits. At this point, it is important to know that kiwis must be consumed in moderation. Be sure to get your daily intake of vitamin C and boost your immunity with kiwifruits, but be mindful of the recommended dietary allowance (RDA). 

A daily intake of 40mg of vitamin C is ideal for your body. Taking more than 1000mg of vitamin C can cause stomach pain, diarrhoea, and flatulence. 

Addressing allergies or specific health conditions.

Allergies to kiwis can take different forms and affect people in different ways. 

Kiwis contain oxalates, a compound present in many other foods, that can cause oral mucosal irritation in some people. It is the irritation in the inside of your mouth, which may involve rawness, redness, swelling, or mouth sores, that are painful. 

Other symptoms of an allergy to kiwis may be: 

• Tingling or sore mouth
• Tight throat and difficulty in swallowing
• Swelling of tongue, lips, or face.
• Rashes or hives.
• Vomiting and stomach ache.
• Wheezing.
• Cyanosis (going blue) and collapse in extreme cases.Moreover, if you have kidney stones (nephrolithiasis) or renal stones (urolithiasis), avoid consuming kiwis. Since kiwis are among the latex fruits (including avocados, bananas, mangos, melons, papayas, etc.), allergy to kiwis may extend to one or more of these products and vice versa. 

Kiwis are recognised as a food allergen in adults and children in the UK. Ensure to check labels and nutritional information carefully to avoid ingesting them. 

In case you observe the above symptoms in yourself or your loved ones or have a known kiwi allergy, visit a licensed healthcare professional for treatment immediately for a personalised emergency action plan. 

Conclusion

Kiwifruit is a nutritional powerhouse, particularly renowned for its remarkable vitamin C content, making it a valuable addition to support immune health. In conclusion, kiwi fruits offer you a whole load of nutritional benefits including: 

• Exceptional Vitamin C Levels: Kiwis are loaded with vitamin C, exceeding the daily recommended intake in just one serving.
• Immune System Support: Vitamin C is a potent antioxidant that enhances immune function, aiding in the body's defence against infections and illnesses.
• Convenient and Tasty: Incorporating kiwis into your diet is a delicious and convenient way to ensure you're meeting your vitamin C needs, contributing to overall well-being and immune resilience.