They Are What You Feed Them: How Food Can Improve Your Child’s Behaviour, Mood and Learning. Dr Richardson Alex

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СКАЧАТЬ complex carbohydrates, which we digest more slowly, are much better for your child than simple starches or sugars.

      Micronutrients

      ‘Micro’ means small—so this term simply refers to nutrients that we generally need in much smaller quantities—vitamins and minerals, antioxidants, flavonoids and some others.

      Vitamins

      Vitamins are substances we absolutely need for health, but which must come from our diet, along with certain essential minerals. Unfortunately, many ‘fast’ foods are devoid of both. Let’s look at some of the main vitamins and minerals your child may be lacking, and see why they’re so important.

      Fat-soluble Vitamins

      Deficiency states are recognized for all vitamins, but let’s start by making clear that in some cases too much can make you ill, too. If you ate polar bear liver, for example (it has happened!), you’d end up dying a nasty death, as just 500g (about half a pound) of polar bear liver will send a lethal dose of vitamin A into your body.

      Fancy Trying Polar Bear Liver? Think Again

      You’ll suffer from:

       a throbbing headache

       stomach cramps

       diarrhoea

       drowsiness

       irritability

       dizziness

       hair loss

       enlargement of your spleen and liver…

      …and to cap it all, before you die, your skin will peel off!

      Why is polar bear liver so rich in vitamin A? Well, vitamin A originates in marine algae, and then passes up the food chain in ever-increasing concentrations until it reaches carnivores such as polar bears, seals and arctic foxes.

      Being stuck in the arctic with only a dead polar bear to eat is unlikely for most of us, but be aware of the risk of vitamin A poisoning. Don’t misunderstand me: vitamin A’s vital for your health, but it isn’t water-soluble, so an excess can’t be excreted in your urine (as happens with vitamins B and C). It gets stored in the body instead. As with all nutrients, you need a balance.

      Vitamins A, D, E and K are all fat-soluble, so any excess is stored in fat-rich body tissues, mainly the liver. Between them these vitamins are responsible for a vast array of functions. You can get them directly from organ meats, some fats (including those in dairy products and eggs) and nut or seed oils, but we make most of our vitamin D from sunlight (if we get enough!), and a healthy gut (if we have one) will house bacteria that produce vitamin K. Let’s see what these vitamins (should) do for your child.

       Vitamin A (Retinol)

      Vitamin A is critical for your immune system, vision, the brain and nervous system, the linings of your gut and lungs, and your bones and teeth. It’s also essential for reproduction and growth.

      In the developing world, vitamin A deficiency accounts for more infant blindness (and thus mortality) than any other single nutrient deficiency. Insufficient vitamin A can stunt your child’s growth, weaken his immune system, damage the delicate linings of his guts and lungs, and impair his vision (particularly in dark conditions). It’s essential to numerous cell-signalling systems in your child’s body and brain.

      Deficiency can reduce appetite and taste, and has been implicated in various autistic-type symptoms, including visual perceptual problems.⁶

      Relatively few foods contain the active form of vitamin A (retinol). Organ meats (liver, kidneys, heart and brain) and oily fish are the richest dietary sources, but egg yolks and full-fat dairy products contain some. An artificial form (vitamin A palmitate) may be added to skimmed and semi-skimmed milk, but in anyone whose gut may be unhealthy (as we’ll discuss in the next chapter) this might not be absorbed properly. Vitamin A can also be made within the body from beta-carotene and other carotenoids. These substances help give carrots and other orange, yellow or green vegetables their natural colours. There’s no danger of accidental overdose with this route, as you only make what vitamin A you need from carotenoids. (As we’ve seen, active vitamin A can be toxic in excess—which is why warnings are issued to pregnant women to be careful about their intake—especially from supplements.)

      According to the latest UK survey, your child is far more likely to get too little vitamin A than too much. In every age group, between one-half and two-thirds of all children were found to be getting less than the official daily ‘adequate intake’ of vitamin A from their diets. For those aged between 11 and 14 years, frank dietary deficiency was found in more than one in eight boys, and one in five girls.⁷ If you think your child’s intake may be too low, you could encourage him to eat more oily fish, liver, pâté or cod liver oil—but only in moderation, as these all provide active vitamin A. You can be more liberal with the carrots, oranges or other sources of beta-carotene from fruits and vegetables, as it’s hard to overdo it on these. The worst that’s likely to happen is that your child’s skin might temporarily turn a harmless shade of orange! (This did actually happen once to someone in my lab who adored tangerines, and ate them by the netful! She was a little alarmed, but came to no harm and learned her lesson: Vary what you eat.)

       Vitamin D

      Vitamin D is critical for building strong bones and teeth, and has extremely wide-ranging influences on most of your bodily systems—and your brain.

      Vitamin D is the ‘sunshine vitamin’, formed naturally by your skin when it’s exposed to the ultra-violet light that accompanies bright sunlight. In summer, you should make enough to last you through the darker days of winter. It’s fat-soluble, so we can store it—but only if we’re exposed to enough sunlight to build up a surplus, or get plenty in our diets. Few foods provide much vitamin D directly. Organ meats (liver, kidneys, etc.), oily fish or full-fat dairy produce are the main dietary sources.

      A severe lack of vitamin D causes rickets (softening of the bones, leading to physical deformities). Less obvious deficiency is a major cause of osteoporosis, and is implicated in unexplained muscle and bone pain. That’s because you need vitamin D—along with magnesium—to actually get calcium into your bones.

      Active vitamin D is also one of the most powerful pre-hormones in the human body. Deficiency can contribute to heart disease, stroke, hypertension, various autoimmune diseases, diabetes, depression, chronic pain, osteoarthritis, muscle weakness, muscle wasting, birth defects, periodontal (gum) disease, and 17 varieties of cancer!⁸ There’s also some evidence that vitamin D deficiency in pregnancy may contribute to hyperactivity and mental health problems in the next generation.⁹

      This being so, it’s not good news that almost one in four children and adults in the UK are seriously deficient in vitamin D each winter, and those who rarely go outside are at risk all year round. What’s СКАЧАТЬ