Winter Flu: Six ‘Superfoods’ To Boost Your Immunity

The flu has hit Spain three weeks earlier than usual and has already reached epidemic levels, with 112.2 cases per 100,000 inhabitants reported, a stark contrast to just 12.8 cases recorded at the same time last year. Meanwhile, searches for “how to avoid getting flu” have skyrocketed by 250% over the past month.

To help keep those pesky bugs at bay this winter, Spanish nutricion expert Ana Prieto recommends six natural immunity-boosting  ‘superfoods’ to add to your diet this cold and flu season.

Beat the flu this winter: Six ‘superfoods’ fitness experts say you should add to your diet

• Black garlic

These aged garlic cloves with a rich, sweet, umami flavour contain 2 to 3 times more antioxidants than their white counterpart. They’re high in S-allylcysteine (SAC) which helps your body absorb allicin for enhanced immune-boosting effects. Studies show these fermented pulps stimulate white blood cell production and have prebiotic effects that nourish gut-friendly bacteria. It’s particularly beneficial to add to your diet when the seasons change, as it is highly effective in treating minor intestinal infections and other winter ailments.

How to incorporate it into your diet? Spread black garlic on toast for a subtly sweet, savoury flavour with hints of molasses and balsamic, mash it into sauces, mix it into marinades or add whole cloves to roasted vegetables, meat or fish dishes. It can also be used as a garnish for salads, soups or pasta dishes without giving you the pungent garlic breath.

• Turmeric milk

Often called the ‘golden milk’, turmeric milk is a traditional Ayurvedic remedy known for its powerful immune-boosting qualities. Its active ingredient, curcumin, is a potent anti-inflammatory, antiviral and antibacterial agent, and when combined with black pepper – which significantly enhances curcumin absorption – it becomes even more effective. Turmeric also supports liver detox, while black pepper boosts metabolism. Its naturally warming properties help improve circulation, making it an ideal bedtime drink during flu season. 

How to incorporate it into your diet? Warm milk and stir in 1 teaspoon of turmeric powder, a pinch of black pepper, cinnamon and a touch of honey. You can also add turmeric to smoothies, porridge or soups for an extra anti-inflammatory boost throughout the day.

• Raw honey

Raw honey, with its natural enzymes and antioxidants, acts as a powerful defence against winter woes. Unlike processed sugar, it contains bioactive enzymes, vitamins, minerals and antioxidants that work together to support the immune system, reduce inflammation and help the body fight off minor infections. Its natural antibacterial and antiviral properties make it a versatile ally during flu season, helping to soothe sore throats and ease cold symptoms. 

How to incorporate it into your diet? Drizzle raw honey over porridge, yoghurt or fruit for a naturally sweet boost, or stir it into herbal teas or hot drinks for a soothing winter beverage. Combine with ginger, turmeric or cinnamon to create easy home remedies for sore throats.

• Matcha

Matcha is a finely ground green tea powder that delivers a concentrated dose of nutrients and antioxidants as you consume the entire tea leaf, not just an infusion. Containing ten times more antioxidants than regular green tea and rich in vitamins A, B2, C, E and minerals like potassium, magnesium and calcium, matcha helps keep your body strong and resilient during the colder months. Its natural combination of caffeine and L-theanine provides a steady energy boost to help combat winter fatigue. 

How to incorporate it into your diet? Whisk matcha into hot water for a calming tea, stir it into baked goods like cookies or add it to your pancake batter. Even a small daily serving delivers a strong antioxidant punch, and could even aid digestion to reduce bloating after heavy meals.

• Citrus fruits

Citrus fruits like oranges, lemons and grapefruits are at their peak from December through March, delivering maximum flavour. Rich in vitamin C, they support the immune system by enhancing the production and efficiency of white blood cells – the body’s frontline defence against infections. Citrus fruits are also packed with natural compounds that help protect your cells, reduce inflammation and support digestive health. Eating them regularly can strengthen your body’s defences during the colder months.

How to incorporate it into your diet? Add citrus slices to water, toss segments into salads or swap processed snacks for whole fruits. Use zest in dressings or roasted vegetables, and sprinkle segments over fish, poultry, or grain bowls for extra flavour and nutrients.

• Shiitake mushrooms

Shiitake mushrooms are naturally rich in beta-glucans, bioactive fibres that help activate white blood cells and boost the body’s immune response. Low in calories but packed with vitamins, minerals and powerful bioactive compounds, they also contain AHCC (Active Hexose Correlated Compound), shown to enhance immunity after exposure to the flu virus. A study has shown that people who consumed shiitake mushrooms for four weeks demonstrated improved immune markers and reduced inflammation. 

How to incorporate it into your diet? Add a handful of fresh or dried shiitake mushrooms to soups, stews, stir-fries or sautés a few times a week. Cook them gently to preserve their beneficial compounds and maximise their immune-boosting potential.

Ana Prieto said: “Winter is a challenging time for our immune systems. Colder temperatures, reduced sunlight and increased exposure to viruses can weaken the body’s defences, leaving us more vulnerable to seasonal illnesses like colds and flu. Supporting the immune system during this time is crucial for fighting off infections and maintaining overall health and wellbeing.

Making small changes to your diet by incorporating nutrient-dense, immune-boosting superfoods can make a real difference. Foods rich in antioxidants, vitamins and bioactive compounds provide a natural shield against infections and help keep the body resilient throughout the colder months. Staying active is also key, even simple practices like brief stretching sessions, a 15-minute morning yoga routine, climbing stairs or a quick online cardio session can prevent stiffness, boost circulation and maintain energy levels, helping your immune system stay strong all winter long.”