By Catherine Jeans DipION mBANT CNHC The Family Nutrition Expert.
It’s that time of the year where sniffles, tummy bugs, coughs and flu start to set in, but the last thing you want is missed days off school or work. The central heating might have gone back on, we spend less time outside and the kids are feeling a bit tired from being back at school… it’s no wonder you may find your family’s immune system in need of a boost.
Guest writer Catherine Jeans is The Family Nutrition Expert, an experienced nutritional therapist who educates families on how to eat well for optimum health. In this article she offers easy and innovative ways to boost your immune system on a daily basis, with sneaky tips on how to get the kids eating more immune-boosting foods.
Clean out the sweet stuff…
Most of us know that sugar isn’t good for us, but we may not be aware of the dramatic impact it can have on our immune systems and ability to fight off infection.
As far back as the 1970s, Linus Pauling, one of the forefathers of nutrition research, discovered that sugar can stop your body from using vitamin C to fight infection, by competing for vitamin C receptors on our white blood cells. In the same decade, researchers found that sugar can directly affect the activity of our white blood cells, our immune army. They found that 100g of sugar (equal to a large bottle of fizzy drink) can make your white blood cells 40% less effective at killing germs for up to 5 hours.
Sugar may also affect the delicate balance of living bacteria in the digestive system, which help to keep the immune system balanced and strong. If we eat too much sugar and also white refined carbohydrates such as white bread, cakes, biscuits and pastries, we may end up affecting the delicate balance of living organisms in our bowels and, in turn, the response of the immune cells in the gut. More about these bacteria later on.
The Sweet Truth
Given the issues with sugar and immunity, there’s no better time to clean up your family’s diet and really have a good look at how much sugar you eat. One of the things I do with children and families is to get a glass and actually measure out how many teaspoons you consume in a day. You might be shocked! It’s a really visual way to show children just how much sugar they are eating. Whilst most kids know sugar isn’t good for them, they probably have no idea how much they consume. For example, strawberry yoghurt… 4 teaspoons…. Packet of sweets…. 6 teaspoons…. Chocolate milkshake…. 4 teaspoons…. Energy drink…. Up to 20 teaspoons!
Also clean out your cupboards of anything with high levels of added sugar, and adjust the way you shop. Watch out for breakfast cereals, cereal bars, flavoured yoghurts, jarred sauces and cordials. You’ll be surprised that within a week of following a low sugar diet, your taste buds can be re-educated very quickly and you won’t even enjoy those sugary foods anymore.
If you do fancy something sweet, look instead for a nutrient-packed option rather than empty calories. Here are a few things you could try with your family:
- Home-made instant ice-cream: blend some frozen fruit with natural yoghurt or coconut milk for instant ice-cream. In our house, we love banana, dark cocoa powder and plain yoghurt. Try blueberries, silken tofu, a squeeze of honey and some fresh mint leaves. (I also often sneak in some powdered probiotics or a bit of omega-3 fish oil into these ice-creams!)
- Choose fruit for natural sweetness: stewed or baked apples are wonderful in autumn and winter, topped with a little natural yoghurt or crème fraiche. Just use cinnamon and other spices for sweetness. You can also make natural plain yoghurt sweeter by blending it with some fresh fruit or frozen berries.
- Dark chocolate – the darker the better in terms of nutrient value and goodness, but just a few squares of minimum 70% cocoa is usually enough to satisfy any chocolate craving. It’s packed with magnesium and iron which are also great for the immune system, and lower in sugar than milk varieties. If your kids won’t go straight to dark, look for good quality brands of milk chocolate that are higher in cocoa solids, and gradually work up to 70%.
- If you like to bake, use bananas, a few dates (not too many) or perhaps a natural sweetener such as stevia or Xylitol.
Get in your greens!
Dark green leafy vegetables really are an all-round superfood… packed with fibre to feed the good bacteria in your gut, as well as Vitamin C, B vitamins, magnesium and antioxidants, all key nutrients for a healthy immune system.
Dark green leafy vegetables include kale, spinach, broccoli, dark lettuce such as rocket, also chard and watercress. Use a combination of raw and cooked green veggies. When you eat them raw you preserve the levels of vitamin C, although cooking lightly in a little coconut oil or organic butter can help to release the bioavailability of antioxidants such as the carotenoids, so important for white blood cell production and natural killer cell activity.
If your children (or partner!) won’t eat their greens, do whatever you can to hide them in food. Here are some of my top tips:
- Make green mash and call it alien mash – mixing in some well cooked broccoli or finely chopped cooked spinach or kale.
- Disguise the greens in soup, bolognaise or shepherds pie – again finely chopping your greens or blending them into a thick winter soup.
- Try some green smoothies… I find children usually accept a green “alien juice” when it’s sweetened with some fruit and made smooth with avocado. Give this combo a go: blueberries, small handful of kale (thick stalks removed) or spinach, half an avocado, water and a couple of dates.
- Broccoli cupcakes – you’ll find loads of recipes online for vegetable cakes. My favourite is chocolate broccoli cupcakes, with cooked puréed broccoli added to the mix.
Did you get enough sunshine this summer?
You may be surprised to hear that over 80% of the UK population could be low or deficient in vitamin D. This nutrient is so vital for the immune system, yet we get the majority of it from the action of the sun’s rays on our skin. The problem is that most of us do not get enough healthy sun exposure, and therefore don’t top up our vitamin D levels enough for the winter. So I always advise that the whole family take a liquid vitamin D3 supplement from around October to June.
Good fats and the immune system
We are learning more and more about the role of essential omega fats and the immune system, and some studies are revealing that omega-3 fats may actually enhance the activity of our immune cells. One study showed that DHA omega-3 fish oil may help to increase the activity of B cells (a type of white blood cell) and antibody production, all key components in the complex functioning of the immune system.
A more recent study has found that supplementation with EPA and DHA, both long-chain omega-3 fatty acids, may also help to support immune cell signaling and enhance immune cells’ capability to destroy pathogens which may cause infection and disease. This study was done in women of around 65 years of age, so we are yet to see the effect on younger people, but it is promising research which may demonstrate a key link between omega-3 fats and the immune system.
Oily fish are the best source of omega-3 fatty acids, with mackerel, sardines, salmon and trout being good sources. You’ll also find omega-3 fats in nuts and seeds, however these have to be converted in the body (and not always very efficiently) into the longer chain omega-3 fats. If you struggle to get your family to eat fish, here are some of my top tips:
- Make fish cakes with cooked salmon and sweet potato, with added flavours such as chilli or ginger. Make into patties, coat with bread crumbs and gently fry or grill.
- Use fresh salmon without skin to make home-made fish fingers. Cut into strips, coat with a little flour, then beaten egg, then a mix of ground almonds and seasoning. Gently grill or fry.
- Make a smoked mackerel dip. Take the skin from the fish, and blend the meat with some cream cheese, silken tofu or natural yoghurt, adding perhaps some spring onions, lemon zest and a bit of horseradish for flavour. Serve as a dip with veggie sticks or on a cracker or toast.
Feed the good guys, keep out the bad guys!
The microorganisms in the digestive system play a huge role in the immune system, and it’s vital to help support the delicate balance of good microflora over bad. These good guys, such as lactobacillus and bifidobacterium play such an important role in the immune system – from helping to prevent infection from pathogenic bacteria that may cause tummy bugs to activating the immune army that gets sent out around the body to fight germs.
You can help support the trillions of these important friends in our bowels by including plenty of soluble fibre in your diet – which comes from nuts, seeds, pulses, wholegrains, fruit and vegetables. Aim to include at least one fruit or vegetable with every meal and snack… and if your family are not keen, here are some sneaky ways to improve their soluble fibre intake.
- Add nuts and seeds to baking – grind them up fine so they won’t even know they are there
- Use fruit to add sweetness to baking – such as grated apple or a mashed banana
- Add pulses such as chickpeas or lentils to a bolognaise or stew – not only will your meat go further, you’ll be adding lots of soluble fibre to feed the friends in your bowel
- Switch to wholegrain carbs and avoid white carbs – if your family complain about wholegrain pasta, use half white and wholegrain and gradually make the switch. If your children won’t eat wholegrain bread, go 50/50 first and gradually make the change.
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