My granny turned 98 this week and we sang Happy Birthday over Zoom and watched her blow out candles.Not 98 of them, thank goodness; my aunt had the forethought to just use two … two years to 100! I would love to say that the secret to her long life has been daily shots of organic wheat grass and meditation at dawn, however she’s always been a massive fan of butter, coffee cake and sherry. Before you go thinking that anything goes though, let’s not forget that her intake of Doritos, Diet Coke and Skittles stands at zero. I firmly believe that it’s the processed junk that has been our ruin. There’s got to be room for the real stuff in moderation! Having lived through the war and raised four children, granny has her fair share of stories. My favourite though is about the time she threw a plate at my grandpa. He wasn’t really the kind of man you throw a plate at, but she did it anyway after he strolled in from a day of cricket and asked if she’d packed up the house and had all the kids ready for their holiday. I can imagine the kind of day she’d had … trying to get organised, laundry everywhere, hungry kids asking for snacks, sibling quarrels, a thousand questions, not a single second to herself. It’s amazing more spouses don’t get murdered really. Fortunately, there was neither murder nor jail time.My granny spent her birthday tucked away from Covid-19 at my aunt’s house in England. It’s a relief to know that she’s out of harm’s way, or as out of harm’s way as she can be.Now, not that I wish to bang on about our current health crisis (because couldn’t we all use a break?) I just feel like we need a refresher on vitamin D. I wrote about this a while ago but since then there’s been more and more experts jumping on the vitamin D bandwagon. And although it’s hard to get experts to agree on anything, there are a few messages we’re receiving loud and clear unanimously:1, Wash your hands2, Social-distance3, Manage your weight and any metabolic disease4, Optimise your immune function in general5, Take vitamin DSo first up, when it comes to preventing yourself catching Covid-19, the most effective measures are handwashing and social-distancing. We know this. It’s so infectious that even then, even the healthiest person can catch it! What we’re really looking at here is resilience and how our diet (and lifestyle) can help to reduce symptoms and improve our ability to bounce back.Just like describing something as “detoxifying”, saying something is “immune boosting” is a little controversial. There is research that indicates certain nutrients (especially antioxidants such as zinc and vitamin C) help to support immune function — but some professionals challenge this concept. However, in nutritional therapy, we routinely see how healthy diets packed with the good stuff help to improve resiliency. Ultimately, I think it’s this simple: what you eat and drink can either build you up or knock you down. It can either make it harder for your immune system to function well, or easier. In that sense, yes, your diet can be immune-boosting — especially when it comes to antioxidants. Antioxidants are found in fruit, vegetables, unroasted nuts/seeds, herbs/spices and green tea. When it comes to fruit and veg — the deeper the pigment, the greater the antioxidant content. Try including berries at breakfast, carrots with hummus as a snack, salad at lunch, fruit and nuts in the afternoon and two servings of dark green veg with dinner — then you would knock it out of the park! (Note: frozen fruit and veg is fine but when it comes to veg, steam it to cook it, instead of boiling. Boiling can deplete nutritional value by 70 per cent.)But even if you’re still on the fence when it comes to antioxidants, it’s worth getting off the fence when it comes to vitamin D. Of all the research out there on nutritional factors that may be useful for Covid-19, this is probably the strongest. A growing body of evidence shows us that vitamin D is important for supporting immune health and crucially, helps to improve resilience to respiratory infections. (I have put samples of sources from the World Health Organisation and the British Medical Journal on Facebook.) This is especially relevant for people who are deficient in vitamin D but I think it’s important for everyone. As such, please note the following:• You can’t really get enough safe sun exposure to fulfil optimal vitamin D requirements, so supplementing is a good idea. • Even if you are not medically deficient, small daily doses are perfectly safe and it’s easier that overwhelming our doctors with testing requests at this stage.• Small daily doses are not only safer but more efficient than mega-dosing.• Most multivitamins contain adequate vitamin D. All our Garden of Life multivitamins at Miles Market (kids, women’s, prenatal, men’s) contain optimal levels of vitamin D in a highly bioavailable form. They also offer great nutrient synergy (adequate levels of vitamin A, C and E are all important to protect vitamin D in the body). But there are plenty of other quality brands out there — just look for one that contains at least 500ius (kids) and 800ius (adults). • For infants and very young children, paediatric drops are available at all pharmacies. If you just want straight up vitamin D then Inside Out Wellness Centre stocks great organic drops.• Multivitamins should always be taken with food but as vitamin D is fat soluble, it’s best taken with food that contains good fats (nuts, seeds, olive oil, avocado, fish, full-fat organic dairy). For infants and young children breast milk and formula do provide sufficient fats. Good news!• Avoid fried food as that inhibits the absorption of vitamin D. This is a big one! Don’t take your supplement with a burger and fries and expect optimal absorption. You’ll just be wasting your money.• The best dietary sources of vitamin D are animal products and include salmon, organic full-fat dairy and eggs. This means that vegetarians and vegans should be especially vigilant about supplementing vitamin D.As I see it, taking a vitamin D supplement is one of the easiest things you can do to optimise your respiratory resilience. Of course, if you are on any medications or have a health condition, it’s always wise to check in with your physician first. Please remember, too, that although it’s an uncomfortable conversation we’re learning that obesity and metabolic disease (heart disease, diabetes) increase vulnerability to the severity of Covid-19, meaning that people with these issues are more likely to have bad or fatal symptoms. There is no getting around that and it’s not an easy topic given how prevalent these things are in Bermuda. So, when it comes to boosting your resilience to Covid-19, optimising your weight and managing your risk factors are of prime importance. The same is actually true for asthma and if you have asthma (like me) you need to make sure it’s well controlled. Remember your preventer takes two weeks to really kick in, so please take it daily.If you have any questions, I’m happy to help. Head over to social media and find me there!• Catherine Burns is a qualified nutritional therapist. 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