Eating well can aid effective brain development
So-called clean eating focuses on foods in their whole, natural state and avoiding processing and additives wherever possible – but clever eating is all about ensuring an adequate intake of the brain-boosting nutrients that can help keep our minds sharp.
The brain is the most complex organ in our body, weighing about 3lb and containing in the region of 100 billion nerve cells. Just like our heart, lungs or any other organ it requires the right nutrients and environmental factors for peak performance.
Some of the most important players are the vitamins, B, C, D, E and K, the minerals iron, magnesium, zinc and iodine and a family of essential fatty acids along with healthy habits such as exercise, mind games and minimising damage from alcohol, smoking and obesity.
But public health nutritionist Dr Emma Derbyshire warns that modern diets mean many of us are not getting enough of these important nutrients and low intakes of omega-6 are particularly problematic.
“The balance of omega-6 to omega-3 is important for brain health and up until the Victorian era the ratio between the two was around one to one,” she explains.
“Since then our consumption of oily fish, which is the best source of omega-3, has plunged while consumption of omega-6 has soared due to wider use of soy and vegetable oils. Now the ratio of omega-6 to omega-3 could be as high as 50 to one.”
And that is a problem as these two fatty acids compete for the same metabolic pathways and higher intakes of omega-6 mean lower levels of the omega-3 fats DHA, needed for mental development, and EPA, which appears to play a role in signalling between brain cells.
Childhood and teenage years
Brain growth is completed by five or six years of age, although maturation continues, and providing an adequate supply of nutrients and minerals from your diet is especially important during this period of rapid growth and development.
Data from the DHA Oxford Learning and Behaviour study has shown that seven-to-nine-year-olds who had under performed on reading tests showed significant improvement after taking 600mg of omega-3.
A diet high in junk food can be damaging to a developing brain
“Attention deficit hyperactivity disorder, dyslexia, dyspraxia and autism spectrum disorders are all associated with a relative lack of omega-3 fatty acids,” says Dr Derbyshire.
The teenage brain is still under a state of construction, continuing to gather DHA up to the end of adolescence. During this period neurons multiply and begin to build more and more connections but synapses which aren’t used will whither and fade away so any intellectual activity will strengthen cognition.
Some experts now believe that brain power is a little like bone density and the more we build in the first half of life, the greater the cognitive reserves we have to draw on, lowering the risk of dementia as we get older.
And while the omega-3 fatty acids DHA and EPA continue to be beneficial, studies suggest that high intakes of saturated, trans fats or sugar are damaging. Animal studies have shown that a high-fat and sugar junk food diet impairs neural activity in the hippocampus.
20s and 30s
MRI scans of more than 4,000 people over 30 years have shown that brain development continues until about the age of 25, although Professor Beatriz Luna, from the Laboratory of Neurocognitive Development at the University of Pittsburgh, says: “Most of the brain’s systems are good to go in one’s 20s.”
Areas of the brain involved in identifying errors continue to undergo change until we’re in our mid-20s, suggesting wisdom really does come with age, although it’s a lot earlier than we might think.
Vitamin E, which is found in avocados and nuts, may help ward off depression and a diet high in fruit and vegetables supports vascular health, a factor in dementia.
Professor Daniel Potts, president of the Cognitive Dynamics Foundation at the University of Alabama, says: “The overwhelming evidential data is that antioxidants do help brain function.”
Keeping active mentally and physically can help head off problems.
Keeping physically active in your 20s can help ward off health problems
As Dr Doug Brown, of the Alzheimer’s Society, says: “What is good for your heart is good for your head and there are simple things you can start doing now to reduce your risk of developing dementia.
“Regular exercise is a good place to start as well as avoiding smoking and eating a Mediterranean diet.”
Early onset dementia is far more common than was previously thought. Research by the Alzheimer’s Society has revealed there are more than 40,000 under-65s who are affected, including thousands of cases in 40-somethings.
Seven out of 10 over-50s have some degree of memory loss and more than half have a friend or family member whose memory is failing, research by supplements firm Equazen found.
Dr Derbyshire says: “A growing body of evidence suggests that higher intakes of omega-3 fatty acids can be beneficial for the ageing brain.”
A randomised-controlled trial in 485 adults aged 55 and older found that those taking 900mg of DHA a day improved immediately and delayed verbal recognition memory scores after 24 weeks. Learning scientists at the Tsinghua University in Beijing have shown that magnesium, found in beans, nuts and whole grains, improves memory.
Top 10 things to do to ward off dementia
Lead researcher Professor Guosong Liu points out: “Half the population of industrialised countries has a magnesium deficit, which increases with ageing.
“This may very well contribute to age-dependent memory decline and increasing magnesium intake might prevent or reduce such decline.”
“The brain shrinks with increasing age and there are changes at all levels from molecules to its morphology,” says Dr Derbyshire.
The antioxidant vitamins A, C, E and selenium have been shown to reduce inflammation in brain neurons and stall cognitive decline.
A recent meta-analysis found that episodic memory – our ability to remember times, places and associated emotion – significantly improved with DHA and EPA supplementation, especially in older adults who already had memory complaints.
The vitamin B12 found in fish reduces brain shrinkage as we age
Scans have shown that vitamin B12, which is found in meat, fish and dairy products, reduces brain shrinkage as we age, which is thought to be a factor in dementia. Vitamin D deficiency, which is common in Britain, increases the risk of dementia.
Researchers at Exeter Medical School have shown that mild deficiency ups the odds of problems by 53 per cent while severe deficiency increases the risk by 125 per cent.
Lead author David Llewellyn admits: “We expected to find an association but the results were surprising. The association was twice as strong as we anticipated.”
Dr Derbyshire says: “There is good evidence that eating oily fish, exercising, keeping our brains active, drinking moderately and avoiding tobacco will all support our brain health.
“But the National Diet and Nutrition Survey shows that most of us don’t get anywhere near the recommended amount of omega-3. Taking a top-up is another way to bridge this gap and the Equazen range offers specially formulated evidence-based supplements designed to support brain health at every age.”