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

Чтение книги онлайн.

СКАЧАТЬ present—within limits. It isn’t the overall quantity of protein, fat or carbohydrate that really matters, but the quality. We’ll discuss protein briefly in this chapter—but children’s consumption of carbohydrates and fats is so often ‘wrong’ in quality terms that we’ll look at these topics separately in Chapters 7 and 8.

      What’s the right balance?

      The most suitable dietary balance of macronutrients depends on your child’s lifestyle, current health and metabolism. Both low-fat’ and ‘low-carbohydrate’ (high-protein) diets have been popularized in numerous ‘miracle’ weight-loss programmes. Most of these are aimed at adults, but each usually claims to ‘cure’ all kinds of ills at the same time. Generally speaking, none of these diets is suitable for children (or you!), unless prescribed for medical reasons.

      A ‘reasonable’ balance of macronutrients includes around half of total energy (calories) from carbohydrates, one-fifth from protein and one-third from fat—but don’t even think of spending your time trying to calculate this! Some sensible ground rules about what kinds of foods your child should be eating (and which ones to avoid) should be enough, and those are provided, with recipes, in Chapters 10-14.

      The type and quality of proteins, fats and carbohydrates that your child consumes matter infinitely more than the overall quantities.

      Proteins

      Proteins are the main building-blocks of living things, so a regular supply of protein is essential for brain and body growth and maintenance. The very structure of most of our tissues—like muscles, tendons or bones—depends on proteins. The enzymes that assist or enable almost all biochemical reactions are usually made of proteins; the receptors and other channels for signalling within and between cells are mostly made of proteins. Many of the messenger-molecules that carry information via those channels are also proteins, or fragments of proteins called ‘peptides’.

      When we eat and digest proteins, they’re broken down into their component amino acids. There are 20 types of amino acids we use. When we need a new protein, it’s assembled from specific amino acids arranged in a particular sequence (a sequence dictated by your genes). The resulting chain of amino acids then folds up in a special way to achieve the proper structure of that protein. Peptides, which are used as important signalling molecules in many brain and body systems, are simply shorter chains of amino acids.

      There are eight ‘essential amino acids’ that we can’t make for ourselves, so they must come from our diets. You can make the other 12 amino acids your body needs.

      The eight essential amino acids go by the names of: isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. Some lists include a ninth: arginine.

      Don’t worry about learning the names—just make sure your child eats a range of protein-rich foods.

      We need a regular intake of good-quality protein to build, repair and run many body systems, so make sure your child gets enough. Don’t overdo it, though—because too much protein can affect your kidneys—but most people don’t eat too much protein unless they’re on some diet that leaves out much of another food group (like carbohydrates), and that’s not recommended. Your child needs to eat only a handful of protein (a quarter or less of the plateful) at any meal, but just vary the type. This could include lean meat, fish, eggs, cheese, nuts, or beans and pulses.²

      Animal and Vegetable Protein

      Vegetarians need to be aware of the essential amino acids. Most animal foods contain ‘complete protein’, meaning that it provides all the essential amino acids we need. By contrast, most vegetarian foods contain only some of them,³ so the others must be obtained by eating the right combinations of legumes, pulses, nuts and grains.⁴

      Protein—Summary of Key Points

      Proteins play numerous roles. They are:

       a source of amino acids/peptides

       key building-blocks of tissue

       used to translate DNA codes so the correct new proteins can be assembled

       what most enzymes are made from

       signalling molecules (e.g. neurotransmitters)

      Either too much or too little protein can have damaging effects on health.

      Fats (Lipids)

      Fat is not just a convenient store of energy. Certain dietary fats are absolutely essential to your child’s physical and mental health, being needed for:

       the structure and flexibility of all cell membranes

       regulating the transport of all substances into and out of cells

       supporting the immune system, heart and circulation and hormone balance

       maintaining the structure and function of your brain and nervous system.

      Fats are dealt with in detail in Chapter 8, but in summary, saturated (hard) fats like those found in butter, cream and meat fat are not a problem in moderation. In fact, it’s better to use these for cooking than vegetable oils (which can produce toxic fats when heated). Olive oil and other monounsaturated fats (found in nuts and seeds) have some health benefits, but the fats your child needs most are the natural polyunsaturated fats, particularly special ones called omega-3 fatty acids (found in oily fish and flax oils) and omega-6 (found in vegetable oils, grains, meat, eggs and dairy produce). You and your child are far more likely to lack omega-3 than omega-6 fats—which could even be increasing stress, anxiety or depression in both of you.⁵

      Carbohydrates

      Carbohydrates are dealt with in detail in Chapter 7, but basically fall into three types:

      1 Sugars—used for energy and found in fruits, some vegetables, milk and most processed foods and drinks

      2 Starches—used for energy and found in all grains (including rice), all vegetables (especially potatoes) and most refined foods

      3 Fibre—used to help digestion and bowel function and found in vegetables, whole grains and unrefined foods

      Sugars occur naturally in fruit and milk, but can also be man-made (like sucrose or table sugar). We have no dietary need whatsoever for manufactured sugars, and these can play havoc with your child’s blood sugar levels, energy levels, health and well-being, and behaviour.

      Starches are made of many sugar molecules joined together. The body usually breaks them down into simple sugars (mainly glucose), which we use for energy. Some starches (like those found in mashed potatoes or chips, and the ‘refined’ starches in many processed foods) break down very quickly, causing your blood sugar levels to rise too fast. Adding protein (like cheese with your baked potato) СКАЧАТЬ