Want to keep healthy this winter? Then you need a robust and balanced immune response. The choices we make when it comes to diet and lifestyle have a profound effect on how our immune system responds. A weakened defence system can lead to a host of health issues and, in addition to concerns around COVID-19, there are many regular winter germs to face. This makes it even more important to support your immune system this winter.
1) Start with Diet
As a nutritionist it is no surprise that I start with diet. Fundamental to our immune response is a healthy gut microbiota. More than 70% of the immune system is located in the gut. This means if it is compromised it can lead to immune dysregulation and chronic inflammation. Allergies and chronic inflammatory conditions can often be linked to imbalances in the gut microbiota. So focus on foods that nourish your gut bacteria. This includes plenty of colourful plant foods which are good sources of fibre (prebiotics) and polyphenols that have been shown to support the growth of our beneficial bacteria. Polyphenols are the most abundant antioxidant in the human body, and they come from a wide range of plant foods. Examples of polyphenol rich foods include berries, grapes, green tea, seeds, oats and dark chocolate. Prebiotic foods include leeks, garlic, onions, chicory root and Jerusalem artichokes. Add in some fermented foods daily whether that’s yogurt with fruit for breakfast, a kefir shake, sauerkraut or kimchi with your salad or a miso soup. These can all support a healthy microbiome.
2) Focus on Dietary Quality
This is the season to really look at the quality of the food you eat. So ditch the refined and processed carbs which tend to be low in key nutrients. There are a number of key nutrients known to support the immune system. These include vitamins A, B, C, D, K and E, zinc, Selenium, omega 3 fats and certain plant compounds such as quercetin and curcumin. Many nutrients work synergistically to support the immune system, so it is far better to focus on whole foods and as much colour as possible rather than just supplements. That said, it is difficult to obtain sufficient vitamin D in the winter months. Known as the sunshine vitamin as sun is our main source, you can obtain only small amounts from certain foods like cod liver oil, eggs, liver, fish and mushrooms. For this reason, the UK Government recommends all adults take a supplement of 10mcg through the winter months.
We are all probably familiar with the immune benefits of vitamin C. This antioxidant boosts white blood cells and antibody production which helps the body fight infections. This is another reason to consume plenty of fruits and vegetables daily. Those foods particularly high in vitamin C include red pepper, citrus, Kiwi fruit and berries.
Nuts and seeds are also a great choice for immune health. They are good sources of vitamin E, zinc and selenium which all play a key role in immune function. For example, zinc has direct antimicrobial properties – that is why many people will reach for a zinc lozenge when they have a sore throat. Brazil nuts are one of the best sources of selenium which helps the immune system make T cells and natural killer cells which support the immune defence response.
There are a number of other plant compounds known to support immune function. Curcumin is a compound present in turmeric and known for antiviral, antibacterial and anti-inflammatory properties. Drinking turmeric shots or lattes as well as adding it to curries and soups is a great way to increase your intake. To improve absorption, add a little black pepper and fat. Another powerful plant compound is quercetin. Often known for its antihistamine properties, it has come into the spotlight recently for its ability to reduce inflammation and inhibit viral replication. Capers, red onions, red apples, red grapes are all good sources. It is also present in green and black tea.
3) Stress Less
The build up to Christmas can be one of the most stressful times of year and the trouble is those stress hormones can disrupt our immune response. Chronic stress which leads to an increase in adrenaline, noradrenaline and cortisol has been shown in numerous studies to suppress the immune system via a decreased production of T cells and antibodies. So make it a priority this winter to focus on ways to manage and reduce your stress levels. While there are many options it is important to find what works well for you. Examples include gentle exercise particularly outdoors, having a supportive network at home and work, breathing techniques, yoga and meditation. Taking time in the day for yourself – whether a walk, chat with friends or a warming bath is important.
4) Sleep Well
Ever wondered why your sleep patterns can be affected when you’re ill? Sleep is an essential part of recovery if you have an infection. Ensuring good sleep is associated with reduction in the risk of infections and improved response time for recovery. Try and maintain a consistent sleep routine through the winter months and if your sleep is poor this is the perfect time to take steps to improve it. Having a regular bedtime and waking time even over weekends is important and look at general sleep hygiene such as reducing exposure to artificial lights and electronics in the evening, Epsom salt bathing, limiting alcohol and avoiding caffeine in the afternoon.
5) Exercise but not too much!
We all know the health benefits of exercise, and now studies suggest moderate exercise can enhance our immune response too. Find an activity that you enjoy that you can stick to. However, don’t overdo it! Overexercise may actually suppress your immune response. So always ensure you build in some recovery time too.
6) Watch the Booze
With the onslaught of family meals, office parties and nights out, it may be tempting to have a few more drinks than usual. But be mindful of the effects this can have on our immune response. Alcohol can suppress the immune system, raise inflammation and may make it harder to the body to tackle infections. Switch to non-alcoholic options, dilute your regular tipple with fizzy water and try the range of mocktails available if you’re looking for something special.
As we head into the winter months and the festive season, use this opportunity to strengthen your immune system and improve resilience ready to kick start the new year.
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