When the pandemic hit in 2020, the question on everyone's collective conscience was: What is the immune system? And how to improve the immune system? Until then, we spoke of our immunity like we do of our distant neighbour – we know it exists, but do we really know what it is? Suddenly, we began exploring immune boosting foods and exercises for immunity, in an effort to boost the immune system naturally. Five years on, and the question of how to increase the immune system still looms large on our minds. Here, we break down the immune system so you can build yours.
01What is the Immune System?

Think of your immune system as your body's built-in defense team – always on alert and ready to take down unwanted intruders. "The immune system is an intelligent network of cells, tissues, and organs that defends us from infections and toxins," says Payal Kothari, Gut Health Nutritionist, Author of The Gut, and Founder of INUEN Nutrition School & GUTAVATAR. Beyond fighting off illnesses, it also helps your body heal from infections and recover from injuries, making it one of the biggest players in your overall well-being.
02How Does the Immune System Work?

The immune system works overtime by recognising what belongs to your body and what doesn't. When it detects a threat – like a virus or harmful bacteria – it springs into defense mode to protect you. A weak immune system makes you more susceptible to infections. Once you recover, your immune system creates antibodies for better future defense.
03Common Signs of a Weak Immune System

Falling sick occasionally is normal, but if you find yourself getting sick more often than usual, it could be a sign that your immune system is underperforming. There are a few common symptoms that may indicate a weaker immune system:
- Unexplained fatigue
- Frequent cough, cold, and fever
- Weight loss
- Night sweats
- Muscle and body aches
- Gut issues like bloating or constipation
- Acne, rashes, or hair fall
- Brain fog or mood swings
04How to Boost the Immune System Naturally

There is no quick fix for how to improve the immune system – it's not something you can "switch on" overnight. Leading a healthy lifestyle is your first line of defense, which includes immune boosting foods and daily exercises for immunity. "Every plate of food and every night of sleep is an immune signal," explains Kothari. "Immunity isn't built in a day; it's built in daily habits."
Immune boosting foods
If you are wondering how to boost the immune system naturally, start with your diet. "70% of our immune cells live in the gut," explains Kothari. "Your digestive system is your immune command center. A healthy gut microbiome helps regulate inflammation, neutralise pathogens, and build long-term resilience." Here's what Kothari suggests you add to your diet to boost your immune system naturally.
- Citrus fruits

Oranges and lemons are packed with vitamin C – a powerful antioxidant that helps increase white blood cell production. Dr. Kothari suggests adding "amla for vitamin C and antioxidants."
- Leafy greens

"Leafy greens and cruciferous vegetables detoxify and support liver immunity," says Kothari. Spinach and kale are loaded with vitamins A, C, and E, folate, and iron.
- Berries

Blueberries and strawberries are full of antioxidants that protect your cells from oxidative stress and keep your immune system calm.
- Fermented foods

Fermented foods, like yogurt and kimchi, contain probiotics that strengthen your gut microbiome. You can add "homemade rice kanji, pickles, or beetroot kanji to restore good bacteria," advises Kothari.
- Nuts and seeds

From walnuts to sunflower seeds, these deliver vitamin E, zinc, and omega-3 fatty acids, which protect immune cells and reduce inflammation.
- Fatty fish

Rich in omega-3 and vitamin D, fatty fish like salmon and sardines help reduce inflammation and regulate immune cell activity.
- Turmeric and black pepper

These are anti-inflammatory superheroes. "Curcumin reduces inflammation and supports immune signaling," says Kothari.
- Ghee and coconut oil

"They feed gut lining and improve absorption of fat-soluble vitamins like A, D, E, and K," stresses Kothari.
05Exercises for immunity
Staying active does more than just keep you fit – it boosts your immune system. Moving your body helps blood flow, improves circulation, and lets your white blood cells – the infection-fighting heroes – travel and respond to threats efficiently. "It also lowers stress and helps you sleep better," says Namrata Purohit, celebrity Pilates trainer and fitness expert. Regular exercise for immunity helps to clear bacteria from your airways and supports the production of antibodies. Purohit believes "it's about moving smart, not hard." Here are a few exercises for immunity that you can incorporate into your fitness routine.
- Pilates

"Pilates has always been at the center of my approach," says Purohit. "It builds strength, stability, and body awareness while being low-impact and sustainable.
- Walking

Walking improves blood flow, helps immune cells circulate more efficiently, and reduces inflammation. Purohit recommends "combining pilates with regular walks to stay consistent without overloading the body."
- Yoga

Asanas help stimulate the lymphatic system, boost circulation, and ease stress. Mindful breathing techniques can also strengthen your body's natural defenses.
- Strength training

Lifting weights enhances circulation, reduces chronic inflammation, and helps activate the infection-fighting cells.
06Lifestyle Habits to Improve Immune System
Your lifestyle has a bigger impact on your immune system than you might think. These include:
- Adequate sleep

"Rest gives your body the time it needs to repair, recharge, and get stronger," says Purohit.
- A healthy diet

"Staying hydrated and eating wholesome meals gives your body the right fuel," says Purohit. Kothari adds that, "early dinners and 7–8 hours of sleep help to repair gut lining overnight."
- Stress management

Manage stress through meditation, and deep breathing. "This lowers cortisol, which is an immunity killer," says Kothari. She suggests "gratitude journaling for mental wellness, which strengthens physical immunity."
- Avoid alcohol and smoking

Limit alcohol and avoid smoking for a clean lifestyle.
- Sunshine

"Morning sunlight exposure boosts vitamin D and your mood," explains Kothari. Vitamin D is essential for immune system regulation, while sunlight energises the movement of the immune cells and boosts serotonin.
- Supplements

While nutrients are best obtained through a balanced diet, supplements can help fill the nutritional gaps. Some of which, according to Kothari, are:
Vitamin D3 for immune modulation Vitamin C and zinc for antioxidant support Curcumin or ashwagandha for inflammation and stress regulation Probiotics for microbial diversity
- Electrolytes

Electrolytes are a great addition to your routine. "Electrolytes maintain hydration, nerve signaling, and muscle recovery – all crucial for immune balance," says Kothari. Our suggestion is the Liquid IV Hydration Multiplier. It has three times the electrolytes and five times the daily value of Vitamin C and beta-glucan for faster hydration and immune support.
07Expert Tips to Improve the Immune System

- "People underestimate the power of proper breathing. Breathing consciously helps calm the nervous system, reduce stress, and support recovery," says Purohit.
- "Listen to your body and understand when it needs movement and when it needs rest," says Purohit. "That balance helps you stay consistent and strong over time."
- "Add prebiotic foods like onions, garlic, bananas, and oats for good bacteria and postbiotics like buttermilk and fermented rice for beneficial metabolites," says Kothari.
- "Practice mindful eating," says Kothari. "Chew 20–30 times, avoid screens, and eat in a calm state," says Kothari.
- "Take short 15-minute walks after meals to enhance gut motility and nutrient absorption," says Kothari.
Like Rome, your immunity can't be built in a day. "Your immunity doesn't live in a capsule – it lives in your gut, your sleep, and your daily rhythm," says Kothari. And if you are wondering where to begin, just follow Purohit's mantra – KISSS. "Keep it safe, simple, and smart," says Purohit. "Small habits, when done consistently, lead to long-term results."
08FAQs
How can I make my immune system stronger fast?
There's no instant fix for a stronger immune system. The best approach is a balanced, consistent lifestyle.
What are signs of a weak immune system?
Frequent fatigue, unexplained weight loss, body aches, and recurring fevers can all signal that your immune system is underperforming.
What foods improve the immune system?
Focus on a nourishing diet rich in vitamins, minerals, and antioxidants. Include colourful fruits and vegetables, nuts, seeds, and whole grains.
Can you fix a poor immune system?
Yes, you can strengthen it by adopting a balanced lifestyle. Healthy eating, regular exercise, and good sleep are key starting points.
What drinks are immunity boosters?
Hydrating drinks that also pack nutrients are great for immunity. Think electrolyte-rich drinks, green juices and ginger tea.









