Foods to boost brain power
October 27, 2004 Edition -1
Most children find matric stressful, even when they are well prepared. Some have even committed suicide as the pressure mounted.
The exams started nationwide this month, and parents will want to help their children stay physically and mentally healthy through this time. They can do so with the right foods, say the experts.
There is a proven link between what we put into our mouths and how we think and feel, says leading educationist, author and brain researcher Dr Caroline Leaf.
She heads the Johannesburg-based Switch on Your Brain Organisation, and works with government education departments to train teachers, students and business people on how to think and learn optimally.
The right foods protect children's health in body and mind, says Leaf. They also improve marks by boosting academic performance on the exam day.
Of course, parents should feed children well throughout life, but there are times when foods can make the difference between success and failure.
The best diet during exams is the diet of our ancestors, says Leaf. That means lots of fresh foods as close to their natural state as possible, such as meat, fish, chicken and eggs, fresh fruits, vegetables, nuts and seeds, preferably organic.
These foods optimise brain function, says Leaf. They provide the sustained energy needed for hours of intellectual activity. They activate memory by stimulating the release of neurotransmitters, brain chemicals involved in receiving, processing, storing, and accessing information optimally when needed most - during exams.
The worst foods are all the junk, processed, high-carbohydrate foods - some breakfast cereals, breads, cakes, sweets, pies and other foods saturated with sugar, salt, chemical colourants, flavourants and preservatives.
They inhibit brain function. They "cloud" the brain and "fog" thinking by inhibiting the release of chemicals needed for an alert brain.
Breakfast is essential to kickstart the brain on the day of an exam.
Leaf says the worst thing you could give your children is a bowl of highly-processed breakfast cereal, pap or white bread, because of the high-carbohydrate content. It suppresses neurotransmitter functioning and causes spikes - highs and lows - in blood sugar levels. This is bad news because memory recall and optimum cognition (thinking) require stable blood sugar levels.
A good breakfast is boiled or scrambled eggs on wholewheat toast, even bacon and eggs, because of the protein and fat content.
Protein activates neurotransmitters and stimulates memory, says Leaf. And the brain has to have fat, because it is 70% fat. It needs fat from the diet, especially the "good fats" - essential fatty acids or EFAs - because the body does not make them.
EFAs are easily destroyed by food processing techniques and excessive heat during cooking. By their nature, processed foods are low in EFAs.
Leaf joins many international specialists, among them UK nutrition gurus Patrick Holford and Dr John Briffa, in saying that the worst diet for the brain is low-fat, high-carb - the way of eating propagated and popularised by the food industry for decades. Even saturated fat in moderation is nowhere near as bad for our health as we have been led to believe
Fats play a key role in "synaptogenesis", the formation of synapses in the brain that allow information to travel between cells, and be processed, stored and retrieved.
Eggs are an excellent source of good fats, says Leaf, yet they've had undeservedly bad press for decades - again, the result of vested interests in the food industry. They are a perfect food and excellent nutrition during exam time. They are cheaper than refined, processed breakfast cereals, she says.
Fish deserves its reputation as a brain food, Leaf says, especially in its oily versions, such as salmon, mackerel and sardines, that are high in EFAs.
Organic, cold-pressed oils are excellent sources of EFAs, with hemp top of the list, according to Holford. The oils must be stored in dark glass bottles in the refrigerator, as they are sensitive to heat and light.
Other good breakfast options are mince, avocado or a white cheese on wholewheat toast.
A good liquid boost before an exam is a few almonds crushed to a paste and blended with orange or grape juice and fresh pineapple. Pineapple contains an enzyme, bromelain, that activates neurotransmitters involved in memory.
And the best liquid to drink before and during an exam is water, because the brain is 30% water, says Leaf. "Fluidity of memory comes literally from sufficient water in the brain," she says.
Water speeds up brain function. Too little water slows it down and dehydrates the brain. When the brain dehydrates, it releases cortisol, a hormone that shrinks dendrites, the tree-like branches in the brain that store information and create memory. This is seriously bad news for cognitive functioning.
Cortisol also triggers the release of adrenalin, another hormone in the brain, responsible for the body's fight-or-flight syndrome. Adrenalin causes the brain to revert to basic reactions, which is fine if your children's lives are threatened, but clearly not if they are trying to pass an exam.
Leaf says the best snacks your children can eat during an exam are biltong, nuts (particularly cashews and almonds) and cheese. The worst are sweets and chocolates. Sugarless chewing gum is fine, as the chewing action stimulates brain activity.
Sleep is another essential for optimum exam results, says Leaf.
It's the time when the brain consolidates, refreshes and primes memory stores. Too little sleep fades memory circuits, she says.
This makes a high-carb meal - for example spaghetti bolognaise (made from wholewheat pasta), and starchy vegetables such as pumpkin or butternut - a good idea because of the soporific effects on the brain.
When it comes to supplements, some specialists say they're a waste of money. Others say they "fill the gaps" from food lacking in optimum nutrition content.
The experts do advise a good Vitamin B Complex supplement, though, because stress, both physical and mental, deplete the body's stores of B vitamins. This, in turn, blocks the action of acetylcholine in the brain, adversely affecting memory. Good food sources of B vitamins are eggs, liver, soybeans, green beans, lentils and organic, cold-pressed plant oils.
Exercise is another essential during exam time - as long as the workout is not strenuous. Gentle walking, swimming, jogging, cycling and jumping on a trampoline support memory function and help to de-stress students, says Leaf.
Repetitive circular movements, on roundabouts and swings, and playing roly-poly games on the lawn reactivate and settle memory.
