Dr. Raaidah Daniel Discusses the “Importance of Nutrition in Strengthening Immunity” in Circle of Well-being by Union Assurance

What role does nutrition play in strengthening the immune system to fight off diseases and infections?

Nutrition is crucial in strengthening the immune system–which is the body’s defence mechanism–and functions much like an army that protects us from infections and diseases. Just like any army, our immune system needs to be fed properly to function at its best. This can be achieved through nutrient-dense foods and a balanced diet.

For instance, deficiencies in certain nutrients like vitamins A and C as well as proteins can severely weaken the immune system. Proteins, for example, form the building blocks of the immune system; without them, the body lacks a strong defence. That’s why it’s vital that we don’t wait to practise good nutrition habits until we fall ill. Instead, we should maintain a balanced diet both before and after illness to keep our immune system strong.

How does eating a balanced diet contribute to a strong immune system?

You’ve probably heard terms like “eat the rainbow” or “PCF balanced meal”. But, what do they really mean? Essentially, it’s about including proteins, carbohydrates, healthy fats – (PCF) – and vegetables in every meal, because each food group has a unique role to play in supporting the immune system. And, when you eat foods of as many different colours as possible, you can be sure you’re getting a balanced diet with plenty of your macro and micronutrients.

Proteins are not just important in muscle building and repair but also help produce immune cells and antibodies. Healthy fats, such as Omega-3s, have anti-inflammatory properties that promotes good gut health and immune response. Vegetables provide essential vitamins like A, C, D and E, each of which plays a different role in supporting the immune system. For example, vitamin A strengthens our mucosal linings (this is important for skin health), while vitamin D is crucial for the immune response during infections. Minerals like Zinc, Iron and Selenium are also key players in sustaining a healthy immune system.

What are some foods that are effective in boosting immunity?

Often, when people think about boosting immunity, they focus on one or two “superfoods”. However, it’s not just about a few specific foods, but about consuming a variety of nutrient-dense foods. Our Sri Lankan diet, especially a traditional rice and curry meal, is one of the most balanced and nutrient-rich meals when it comes to supporting immunity.

Take vitamin C, for instance. While many associate it with citrus fruits like oranges and lemon, we have other great sources of Vitamin C such and nelli (Indian gooseberry) and leafy greens found in mallums that are typically part of a rice and curry meal.

It’s also important to include phytonutrients- natural compounds produced by plants- in our diet. Phytonutrients protect plants from bacteria, fungi, insects and even viral infections as part of their own immune system. When we eat plant foods, we can also absorb these phytonutrients which in turn helps us to reduce inflammation and strengthen our immune system. We can find these phytochemicals present in a variety of fruits and vegetables that span all the colours of the rainbow!

Some examples of these potent phytonutrients is the powerhouse of herbs and spices found in our staple diet like ginger (gingerols), garlic (allicin) and turmeric (curcumin).

Including antioxidant and anti-inflammatory foods in our diet is also an important part of building immunity. For example, Omega-3 fatty acids, which reduce inflammation and promote gut health, can be found in small, fatty fish like hurulla (spotted sardinella), halmassa (anchovy), and salaya (gold-striped sardinella). Local foods like these are rich in immunity-boosting properties, emphasizing the importance of consuming a diverse range to support overall wellness.

How is gut health related to the immune system?

Gut health and immunity are deeply interconnected. In fact, around 70% of the immune system is housed in the gut, specifically in a part of the immune system known as the Gut-Associated Lymphoid Tissue (GALT)—which essentially acts as the headquarters of our gut’s immune defense.

A healthy gut microbiome, which is the community of beneficial bacteria in our digestive system, plays a pivotal role in maintaining a strong immune system. These bacteria produce short-chain fatty acids that have anti-inflammatory properties and form a barrier that prevents harmful pathogens from entering the bloodstream.

To support a healthy gut, it’s important to consume fiber-rich foods, such as fruits, vegetables and whole grains which act as prebiotics (food for your gut bacteria). Probiotic foods like curd and yoghurt help promote the population good gut bacteria. The health of our gut has a direct impact on the strength of our immune system, so looking after it should be a priority.

Are there any eating habits or diets that can weaken immunity?

Sadly, yes. One of the biggest culprits is, in fact, excessive sugar intake, which is quite prevalent today, unfortunately. High sugar consumption reduces the ability of white blood cells to fight infections, leading to chronic inflammation. Diets high in processed foods, low in fiber and high in unhealthy fats also contribute to inflammation and weaken the body’s ability to respond to infections. These types of diets lead to obesity- which has become a global concern- and results in the accumulation of visceral fat (the fat around organs) which in turn makes the body more susceptible to illness.

Excessive alcohol intake serves as another contributing factors which can negatively impact the immune system. Additionally, proper hydration is another aspect that’s often overlooked–and it shouldn’t be, especially in our hot and humid climate. That’s because adequate hydration helps maintains the mucous membranes in our respiratory and gastrointestinal tracts, which are our first line of defence against pathogens.

What impact does chronic malnutrition have on the body’s ability to fight diseases?

It can have severe and far-reaching effects on the immune system. Protein-energy malnutrition, for instance, affects the production of immune cells, antibodies and lymph organs, which are essential for a strong immune response. This leaves the body vulnerable to infections and prolongs recovery time.

Micronutrient deficiencies such as those involving vitamins A and C can also compromise immunity. For example, vitamin A is crucial for maintaining the mucosal barriers that line our gut and respiratory systems, which protect against infections. When we lack these vital nutrients, our immune system is left weaker and less capable of defending the body.

Conclusion:

As highlighted in the discussion, maintaining a strong immune system is not solely dependent on one or two superfoods but rather on a holistic approach to eating. By embracing a variety of nutrient-dense, locally sourced foods and adopting healthy dietary habits, we can support our body’s natural defences effectively.

The key takeaway? Nutrition is not just about avoiding disease—it’s about cultivating overall wellness. So, start today by making small dietary changes: add more colours to your plate, choose whole foods over processed ones, and prioritise hydration. Remember, a balanced diet today is the foundation for a healthier tomorrow.