Iron deficiency anaemia is the most common nutritional deficiency worldwide, affecting around 2 billion people.  Here in the UK the National Diet and Nutrition Surveys have revealed that most children under the age of 18 have dietary iron intakes below the RNI (reference nutrient intakes).  This is very worrying as iron is important for normal neurodevelopment (development of the brain and nervous system) and deficiency, with or without anaemia, in infants and children appears to adversely affect social and emotional development, intellectual performance and concentration span and has been linked to ADHD (Attention Deficit Hyperactivity Disorder), hyperactivity, aggressiveness, poor mood and fatigue.

The most recent study was published in an American journal in May(1).  The study leader, Dr Betsy Lozoff, is a leading researcher in the field of iron deficiency in childhood.  The researchers looked at the social and emotional behaviour in a group of infants who were 9 months old at the start of the study.  Tests confirmed that around a third of the children had iron deficiency anaemia, a third had iron deficiency without anaemia and a third had sufficient iron levels.  All infants then received a 3 months course of liquid iron supplement.  The supplement was given to all infants, even those with sufficient iron levels in order to prevent deficiency during their transition to being fed cows milk (which is very low in iron). 

At 12 months the infants were assessed.  Those with poorer iron status were more shy, harder to sooth, less likely to be engaged in their surroundings and less likely to orientate themselves in their surroundings.  The associations were present in iron deficient infants regardless of anaemia status.  Dr Lozoff concludes that the results need to be confirmed in larger trials but her findings do add to the ever growing body of evidence that links iron deficiency in children and developmental problems.

Iron is essential in the diet as it is used by the body in the manufacture of the blood protein haemoglobin, which is responsible for the transport of oxygen from the lungs to all cells in the body so that they can generate energy.  If iron levels are very low it can cause a condition in the body called iron deficiency anaemia.  This can be checked via tests which screen for haemoglobin in the blood.  However, individuals can become deficient in iron without becoming anaemic.  Iron deficiency without anaemia is widespread and not detected by the most commonly used screening procedures.  Both deficiencies are related to low mood, fatigue and mental ‘slowness’ in adults(2,3) and a host of behavioural and mental developmental issues in children(4).  It is not entirely understood why iron deficiency is linked to childhood behavioural issues, such as ADHD, but it may be related to the fact that iron is essential for the normal development of the brain and the functioning of dopamine, a brain chemical.  The most accurate way to check for overall iron status is to screen for ‘serum ferritin’ levels, this will pick up on iron deficiency (with or without anaemia).

In infants breast feeding for less than 6 months duration, the use of non iron-fortified infant formula and the introduction of cow’s milk before 1 year of age are risk factors for iron deficiency and in children dietary deficiency is common.  There are two forms of dietary iron: Haem iron (found in meat sources) and non-haem (found in non-meat, vegetarian sources) iron; and the extent to which iron from food is absorbed depends upon the form it is in.  Haem iron is the most easily absorbed form.  However, absorption is greatly affected by other factors. Most importantly vitamin C, found abundantly in fruits and vegetables, is important in promoting the absorption of non-haem iron.  Adding fruits and vegetables high in vitamin C to a meal may triple iron absorption from foods such as wholegrain cereals and pulses.  On the contrary tea and coffee reduce the amount of iron that is absorbed from all foods.  Try avoiding tea and coffee with meals as they can reduce iron absorption by 50%.  Calcium also reduces iron absorption, drinking a glass of milk with a meal can also half iron absorption.  Phytic acid (also known as inositol hexaphosphate) found in peanuts, wholegrains and seeds can greatly reduce the absorption of iron. 

For individuals who are vegetarian or rarely consume meat, wholegrain cereals, eggs, nuts, dried fruit and pulses (beans and peas) will provide adequate iron if consumed as part of a high vitamin C containing meal.  If you are relying on non meat sources of iron you may wish to consider taking a 100-200mg vitamin C supplement with your main meal to ensure good absorption.

Iron is a nutrient that can accumulate in the body and an excess can be damaging so ALWAYS get iron levels checked prior to embarking on a supplementation programme.  When asking the doctor for a test for yourself or your child, be sure to ask for a ‘serum ferritin’ test (rather than a test for anaemia) as this will provide a better indication of bodily iron status. 

Unfortunately, in the UK there is no consensus among doctors as to what a ‘normal’ blood ferritin level should be.  Many doctors who regularly employ complementary medicine would suggest that in children a ferritin level of less than 30ng/ml (30ng ferritin per 1ml blood) or 50mcg/l in adults would indicate a deficiency.  If you have any concerns do talk them through with your GP.

(1)Lozoff B et al.  2008.  Dose-response relationships between iron deficiency with or without anemia and infant social-emotional behaviour.  J Pediatr.  152:696-702
(2)Khedr E et al.  2008.  Iron states and cognitive abilities in young adults: neuropsychological and neurophysiological assessment.  Eur Arch Psychiatry Clin Neurosci. Jun 20. [Epub ahead of print]
(3)Patterson AJ et al.  Dietary and supplement treatment of iron deficiency results in improvements in general health and fatigue in Australian women of childbearing age.  J Am Coll Nutr. 2001 Aug;20(4):337-42
(4)Lozoff B et al.  2006.  Long-lasting neural and behavioral effects of iron deficiency in infancy.  Nutr Rev.  64(5 Pt 2):S34-43; discussion S72-91

Written by Ani Kowal

New research(1) has just emerged from Baycrest which shows that adults with type 2 diabetes who eat unhealthy, high-fat, meals may experience memory declines immediately afterward, but this may be offset by taking antioxidant vitamin supplements together with the meal.

Baycrest is an academic health sciences centre, affiliated with the University of Toronto, which is internationally-renowned for its research on aging and the conditions associated with ageing such as memory loss, depression and stroke.

The study authors make reference to the fact that there is already a growing body of evidence that links diabetes to cognitive (mental) complications in humans.  Adults with type 2 diabetes seem especially vulnerable to acute memory deficits after eating unhealthy foods.  This latest study suggests that taking high doses of antioxidant vitamins C and E with such meals may help minimize those memory slumps.

One of the study authors, Michael Herman Chui, said “Our bottom line is that consuming unhealthy meals for those with diabetes can temporarily further worsen already underlying memory problems associated with the disease”.

The study was a very small preliminary trial that involved only 16 adults (with an average age of 63) with type 2 diabetes who were not regularly taking antioxidant supplements.  They attended three weekly sessions that involved consuming a different test meal on each visit. One meal consisted of high fat foods (a Danish pastry, cheddar cheese and yogurt with added whipped cream); the second meal consisted of only water; and the third test meal was the same high-fat meal plus vitamin C (1000 mg) and E (800 IU) supplements.

After eating the meal, participants completed a series of tests that measured their recall abilities for words they had heard and paragraph information they had read.  It was found that vitamin supplementation consistently improved recall scores.  Compared to those who consumed only water or the meal with antioxidant vitamins, participants who ate the high fat meal showed significantly more forgetfulness (of words and paragraph information) in immediate and time delay recall tests. 

The study authors emphasize that their findings obviously require further replication in much larger trials. Future studies will also need to look at how the antioxidant vitamins may be working.  Personally, I would also like to see further trials using antioxidant foods, such as fruits and vegetables, in conjunction with meals to test if the same benefits are seen as with supplementation (I have a feeling results would be very positive)!

Type 2 diabetes is associated with persistent, long term oxidative stress, a known major contributor to cognitive (mental) decline and Alzheimer disease. Consuming unhealthy foods can induce this type of stress which is triggered by elevations of free radicals: unstable molecules that can damage body tissue, including brain tissue. These destructive reactions tend to occur over a 1-3 hour period after the ingestion of food.  Fruits and vegetables contain numerous antioxidant nutrients and can minimise oxidative stress, it is important to include such foods as an integral part of all meals.  This study showed that antioxidants could reduce immediate memory deficits caused by unhealthy eating.

Dr. Carol Greenwood, senior author of the study, cautioned that relying on antioxidant vitamins at meal time is not a quick fix. “While our study looked at the pill form of antioxidants, we would ultimately want individuals to consume healthier foods high in antioxidants, like fruits and vegetables” (well said!).

An overall healthy lifestyle is important in maintaining optimal mental health at all ages.  This includes regular exercise, staying mentally active, being socially engaged in a variety of activities as well as adopting a healthy diet rich in fruits, vegetables and healthy fats found in oily fish, nuts and seeds.

(1) Chui MH & Greenwood CE.  2008.  Antioxidant vitamins reduce acute meal-induced memory deficits in adults with type 2 diabetes.  Nutrition Research.  28 (7): 423-494
(2) Baycrest press release

Written by Ani Kowal

Last weekend (18/05/08) The Sunday Times ran a story entitled “Superfood celery combats brain diseases”.  Quite timely I thought, as I was in the middle of preparing a post on the important role that dietary flavonoids , also known as bioflavonoids  (a group of over 4000 types of polyphenol plant compounds), play in maintaining mental health e.g. memory, learning and general mental performance.  The newspaper article focussed on the flavonoids, luteolin and diosmin, found in celery and how they may be important in slowing the progress of brain diseases such as Alzheimer’s disease.

A recently published medical review paper(1) brought together evidence for the role of dietary derived flavonoids and mental health.  In this paper Dr Jeremy Spencer, a researcher and lecturer at my old University, highlights a number of studies in both humans and animals which have found that flavonoids, from a variety of dietary sources such as grapes, tea, blueberries, cocoa, onions, broccoli and tomatoes (to name but a few), have beneficial effects on cognitive (mental) performance.  He postulates that the benefits come from the ability of the flavonoids to protect brain neurones, reduce neuronal inflammation, enhance neuronal function and even stimulate neuronal regeneration (regrowth). 

The paper is extensive, however I would just like to mention one study that is reviewed(2).  In this study 1640 individuals, all over the age of 65, were followed for ten years and their dietary habits assessed over that time.  All of them were free of dementia at the start of the study.  Cognitive (mental) performance was examined four times over the ten year period.  Flavonoid intake was associated with a significantly better cognitive performance at the start of the study and throughout the study period.  The individuals with the highest flavonoid intakes were found to have better preservation of mental performance with ageing than subjects with the lowest intakes of flavonoids.  After 10 years the individuals with the lowest intakes were found to have lost an average of 2.1 points on a test of mental performance (the Mini-Mental State Examination) compared to those with the highest intakes who had lost on average only 1.2 points.  Such data provides a strong indication that regular dietary flavonoid consumption may have a positive effect on preserving mental performance with ageing.

As Dr Susanne Sorensen of the Alzheimers Society is quoted as saying in the newspaper “we know a healthy balanced diet can reduce dementia risk.  This work reinforces the need to eat a diet rich in fruits and vegetables”.  There are many dietary factors which can contribute to a healthy brain and positive mood and I am sure that I will address these factors in my future writings!

It is clear that a diet rich in a variety of different vegetables and fruits is really very important for all aspects of health.  There is NO substitute for a diet plentiful in a variety of vegetables and fruits.  Choosing produce with a mixture of colours will provide an array of different flavonoids.  Flavonoid supplements do exist and these may be helpful to take in addition to a healthy diet as a means of boosting intakes.  If you do choose to take a supplement look out for one that provides an assortment of many different flavonoids (they may be labelled as bioflavonoids).

(1) Spencer JPE.  2008.  Food for thought: the role of dietary flavonoids in enhancing human memory, learning and neuro-cognitive performance.  Proceedings of the Nutrition Society.  67:238-252
(2) Letenneur L et al.  2007.  Flavonoid intake and cognitive decline over a 10 year period.  Am J Epidemiol.  165:1364-1371

Written by Ani Kowal