Do you envy those people with steel-trap memories, who are sharp as a tack despite their age? You can be that way too, if you know what nutrients to feed your brain, says dietitian Tracy Morris.
From our expert
A note from our Editorial Advisor, Dr Samir Samman.
Most of us don’t spend too much time thinking about the health of our brain. But with Australian deaths from brain-related diseases, such as dementia and Alzheimer’s disease, more than doubling in the past 10 years, it’s becoming a matter of pressing urgency. So what is good for our grey matter? It makes sense that what is good for the body, would also be good for the brain. But there’s more to the story than that. Much remains to be discovered about the link between mental and physical health, but emerging findings suggest that some nutrients may be more critical to brain health than others. Continue reading to find out more.
Associate Professor of Human Nutrition, School of Molecular Bioscience, University of Sydney
Boost your memory
Most of us accept memory loss as an inevitable part of ageing. But that’s not necessarily the case. In fact, for many of us, a large part of memory loss is caused by the brain having inadequate access to certain vitamins and minerals.
To store, access and transmit memories, the brain uses chemical messengers called neurotransmitters. To make these neurotransmitters, the brain uses certain nutrients derived from food. If you’re not eating the right foods, your brain can’t make the neurotransmitters required to store or access those memories; resulting in memory loss. What this means is that most of us may actually be able to improve our memory, with a few additions to our diet.
There’s been plenty of research to suggest that iron might be vital to an effective memory, but nothing quite as illuminating as a 2007 study published in the American Journal of Clinical Nutrition. The study, which saw 149 women with varying levels of iron in their blood perform a range of mental tests, found that women with sufficient iron levels could answer questions significantly faster, and answer correctly, than those who were iron deficient. That might not seem surprising, but consider this: the study also found that when the iron-deficient women were given 16 weeks of iron supplementation, their scores/mental performance increased by an incredible seven times.
Iron is also crucial when it comes to producing the brain chemicals dopamine and noradrenalin, as well as carrying oxygen to brain tissue. Low levels of these chemicals can negatively affect concentration and memory. Iron is the most common nutrient deficiency in the developed world, which means it’s likely you’re not getting the iron you need to perform at your best. Add iron-rich foods, such as red meat, pumpkin seeds and iron-fortified foods to your diet.
Choline is an essential nutrient used to make neurotransmitters and, like iron, research shows it has a marked effect on memory. In one study, healthy older adults (aged 50 to 80 years) who ate 2 tablespoons of choline-rich lecithin each day showed a marked improvement in memory. After just five weeks memory lapses – like forgetting names and misplacing items – decreased by 48 per cent.
A double-blind study, conducted back in 1993, suggests that just a single dose of choline might make a difference. The researchers gave 80 university students a 25g dose of choline-rich lecithin, and after just 90 minutes, the students were significantly better able to memorise a series of nonsense syllables.
Statistics show that 90 per cent of Americans are deficient in choline; with a similar trend likely in Australia – so up your intake with choline-rich foods, such as eggs, nuts, seeds, soy beans and soy lecithin (you can find lecithin granules in the health food aisle of your local supermarket).
Did you know? Choline is is vital to an unborn baby’s brain development – so being pregnant, and breastfeeding, can cause a mother’s choline levels to become depleted. Scientists theorise that this is a possible explanation for the ‘baby brain’ effect.
Found mainly in fruit and vegetables, folate (also known as vitamin B9) has been identified as a major nutrient in warding off memory loss. In 2004, researchers looked at the levels of folate in the blood of 228 people and found that those with the lowest folate levels were at risk of mild cognitive impairment, and four times the risk of developing dementia. Another study, published in the Journal of Biology and Psychiatry, found that healthy older adults who scored poorly on recall tests were more likely to have low levels of folate in their blood. Not surprisingly, forgetfulness is a symptom of folate deficiency. Add broccoli, bran cereals, asparagus and strawberries to your diet for a folate boost.
Your body uses fluid to transport nutrients to the brain. So even if you are eating the right nutrients, without enough water, they may not be reaching your brain. Studies show dehydration affects not just your memory, but your overall cognitive abilities. When researchers restricted the water intake of 11 healthy adults and asked them to exercise in heated conditions, the adults demonstrated ‘significant deterioration’ to their short-term memory. They also demonstrated impaired mathematical abilities and hand-eye coordination.
Dehydration doesn’t just affect short-term memory, either. A similar study, conducted in 2000, found that dehydration resulting from heat stress also affects long-term memory. Make sure water is your drink of choice, and eat plenty of water-rich foods, such as fruit and veg (tomatoes and grapefruits fit the bill).
The brain needs large amounts of glucose to function – 20 per cent of the body’s entire ‘energy budget’, in fact. Glucose is derivedfrom carbohydrates, which is why eating a sufficient amount of carbs has been linked to an improved ability to concentrate, remember and learn.
However, unlike muscles, the brain cannot store glucose, which means it needs a constant supply for optimal functioning. Therefore, how often you eat can make a difference to the effectiveness of your memory. Regular meals, snacks with a combination of protein and carbohydrates, and low-GI foods all help keep your brain’s glucose supply at a steady rate. We’ve said it before (and you’ll hear us say it again), but it’s important to eat a healthy breakfast, as memory-friendly nutrients are depleted overnight. Scientists demonstrated the importance of breakfast when they gave 64 primary-school-aged children either a sugary breakfast cereal, which quickly boosted blood glucose to high levels, or a lower-GI cereal that gradually raised blood glucose. The kids who ate the lower-GI cereal consistently performed better in memory tests.
We get antioxidants from the foods we eat, but our bodies have an ability to produce their own antioxidants, too. However, the brain has a limited capacity to produce its own antioxidants – so it relies much more heavily on the antioxidant-rich foods you eat to fight off free-radical damage. If you’re not eating enough antioxidant-rich fruit and veg, your brain is especially vulnerable. Several studies have confirmed this link, including a landmark study in 2005 that involved looking at the dietary patterns of more than 13,000 women aged 70 or older. The researchers, from Harvard Medical School, concluded that the link between higher rates of vegetable consumption and a slower rate of cognitive decline was likely due to the high levels of antioxidants in vegetables.
Much research has also centred around one of the most abundant antioxidants found in nature, vitamin C. While our bodies cannot make vitamin C, the brain is able to store high concentrations of this antioxidant when we consume it. Not surprisingly, there’s an established link between vitamin C intake and memory function. Researchers at the University of Sydney confirmed this link when they put 117 retirement village residents through a series of mental tests, including remembering a series of words, and listing words that begin with a certain letter of the alphabet. Those who regularly took vitamin C scored higher than others. Up your intake of ‘C’ with citrus fruits, tomatoes, broccoli, capsicum and strawberries.
The human brain is comprised of nearly 60 per cent fat, and a major component of this is the long chain omega-3 fat, docosahexaenoic acid (DHA). DHA is not only a ‘building block’ in our brains, but is used to make and replenish neurotransmitters (chemical brain messengers) – vital for normal brain functioning. Studies on humans have shown a strong link between omega-3 intake and brain health, including depression and suicide in adults. A review of 10 studies on mood disorders and long chain omega-3s found a significantly reduced risk of developing depression, as well as significantly reduced symptoms of depression in patients with existing depression, in those people consuming long chain omega-3s. Oily fish is a great source of DHA.
Amino acids, molecules that make up protein, have the ability to excite or calm our brains. In doing so, they may play an important role in keeping us alert, happy and better able to cope with stress. One amino acid, tyrosine, has been found to help create the brain chemicals that keep us feeling energised and alert – even under stressful conditions. While another, tryptophan, appears to help form the ‘happy’ hormone, serotonin. To make sure you’re getting a rich supply of amino-acids, eat protein-rich foods such as soy, red meat, poultry, fish, nuts and seeds, milk, cheese and yoghurt.
It seems having something for breakfast may also put you in a better mood, with research showing breakfast eaters feel less depression, less emotional distress and less stress. A steady supply of energy helps regulate mood and can help temper anxiety. Whole foods New research from the University of Melbourne shows sticking to the ‘old fashioned’ way of eating – opting for whole foods (foods in their ‘whole’ state, ie – fruit, vegetables, wholegrains, meat, fish, chicken, eggs, etc) over highly processed foods, such as meat pies, processed meats, fast food, white bread, and sugary drinks, may help prevent depression and anxiety.
New research from the University of Melbourne shows sticking to the ‘old-fashioned’ way of eating – opting for whole foods (foods in their ‘whole’ state, ie. fruit, vegetables, whole grains, meat, fish, chicken, eggs, etc) over highly-processed foods, such as meat pies, processed meats, fast food, white bread, and sugary drinks – may help prevent depression and anxiety.
Zinc is also one of the most abundant minerals found in the brain. It is involved in shaping an infant’s developing nervous system and maintaining structure in adults. There is some research to support a link between low zinc levels and an increased risk of developing depression, especially in people at risk of developing the disease, so it’s important to maintain zinc levels by eating foods such as red meat, wheat, nuts and seeds.
Did you know? There's a strong link between beating depression and exercising – so lace up your sneakers and see Australia's best winter workouts for some inspiration!
Several studies have shown a link between eating more fish (and therefore, long chain omega-3s) and a reduced risk of dementia – including a recent, large population study of people living in Latin America, China and India. While this link has not been found in other population studies, making the research findings somewhat controversial, omega- 3s have a proven link to brain health (see ‘beat depression’), so make sure you’re getting enough.
A recent USbased study showed that following a Mediterraneanstyle diet was associated with a 38 per cent reduction in the risk of developing Alzheimer’s disease. The diet consists of higher intakes of nuts, fish, tomatoes, poultry, cruciferous vegetables (such as cauliflower and Brussels sprouts), fruits, and dark and green leafy vegetables, as well as a lower intake of high-fat dairy products, red meat, organ meat and butter.
Homocysteine is an amino acid found naturally in the blood. Having too much, however, can increase the risk of Alzheimer’s disease and other dementias (not to mention heart disease and stroke). Folic acid and vitamins B6 and B12 help break down homocysteine, and studies have shown that getting plenty of these nutrients in your diet can help reduce high levels of homocysteine and delay dementia. A Korean study showed folate (vitamin B9) deficiency may increase the likelihood of developing dementia by as much as 3½ times. Legumes, milk and bran cereals are good sources of B vitamins.
According to Alzheimer’s Australia, antioxidants are also important when it comes to avoiding dementia. It’s thought that free radicals may contribute to brain cell death, leading to Alzheimer’s disease or dementia. Studies previously looking at whether antioxidants protect against dementia have shown vitamins C and E, and beta carotene, could be protective. Although these findings are not yet conclusive, it doesn’t hurt to up your intake of fresh fruit and vegetables to top up your antioxidant intake!
Can curry keep you clever? The high consumption of curcumin, an Indian curry spice derived from turmeric and a potent antioxidant, is thought to contribute to the low prevalence of Alzheimer’s disease in India.
Help your kids perform better
Just like adults, food can make a difference to your child’s memory, concentration levels and overall mental health. In fact, most brain growth is completed by 5–6 years of age, so make the most of those early years by feeding your kids all the nutrients we’ve listed in this article. Studies have also shown that:
Omega-3 is important not just for warding off depression and dementia – it’s been linked to higher intelligence in childhood.
Iron is important in the classroom – low levels of this nutrient affect childrens’ ability to learn.
Zinc is linked to ADHD (Attention deficit hyperactivity disorder). Many children with ADHD have lower zinc levels compared to healthy children – and zinc supplementation has been found to have a positive effect on their behaviour.
A low-GI breakfast may help to maintain kids’ attention and memory throughout the morning.
Can you improve your baby’s IQ?
Research does suggest that what you eat during pregnancy and breastfeeding can impact their brain development. Some of the key findings include:
Iodine is crucial for normal brain development before birth, with iodine deficiency being by far the most common, preventable cause of developing low IQ.
Zinc – there is evidence that not getting enough zinc during pregnancy and while breastfeeding can result in less focused attention and impaired motor development in the baby.
Folate is key to the growth of a healthy neural tube (which later develops into the baby’s spinal cord and brain).
Choline may help improve the function of a baby’s lifelong memory. If you are pregnant or breastfeeding, eat choline-rich foods such as eggs, dairy, peanuts and soybeans.
Omega-3 (or more specifically, the long-chain omega-3, DHA), is vital for normal brain development in children. Breastmilk is a very rich source of DHA, but formula enriched with DHA omega-3 is also a viable alternative for mothers who aren’t breastfeeding. New Zealand researchers also found a six point advantage in verbal IQ for babies who received breastmilk for eight months or more, compared with those who did not receive breastmilk.
If you are considering becoming pregnant, currently pregnant or breastfeeding, consult with your doctor or dietitian about taking vitamin and mineral supplements that contain iodine, iron, zinc, folate and omega-3s to assist with your baby’s brain growth and development.
Brain boosters – what they do and where to find them
Function in the brain
Crucial for normal brain, development before birth
Seafood, seaweed, iodine-fortified bread, iodised salt
Zinc Involved in shaping the developing nervous system and maintaining its structure
These foods can have a negative impact on your brain health, so don’t overdo them:
Alcohol: Drinking even in small amounts decreases our ability to think clearly and in excess causes brain damage.
Trans and saturated fats: ‘Bad’ fats appear to accelerate mental decline and increase the risk of dementia.
Fish that contains high levels of mercury: Mercury, transmitted from a mother to her foetus, may affect the baby’s brain development. Some fish that contain high levels of mercury include shark, orange roughy, swordfish and ling.
Sugary drinks and snacks: According to research published in 2003, kids breakfasting on sugary drinks and snacks performed at the level of an average 70-year-old in tests of memory and attention.
Fad diets: A study on rats showed feeding them a high protein, low carbohydrate diet made their brains shrink, possibly putting them at risk of Alzheimer’s disease.
The bottom line on brains
What you eat really can make a big difference to your brain. Eat the right foods to keep it well-oiled with healthy fats, well-protected with antioxidants and well-stocked with nutrients it needs, and you’ll be on the road to being the sharpest tool in the shed.
Of course, as much as food can help or hinder your efforts to stay brainy, don’t forget that other, non-food-related factors – such as how much sleep and exercise you get, how well you cope with stress and the strength and support of your relationships with friends and family – can have just as great an effect (or even greater) than your diet. If you’re concerned about your mental health, the health of your brain or if you have questions related to Alzheimer’s, it’s important that you contact a qualified health professional.
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