One of my close friends is pregnant (I am very excited)!  We were chatting about pregnancy health and the topic of preeclampsia came up.  Recently a study(1) was published which suggests that increasing the amount of fibre eaten during early pregnancy may help to reduce the risk of preeclampsia developing later.  I thought now was as good time as any to look into this complex topic further!

Preeclampsia is a serious condition also known as: pregnancy-induced hypertension (PIH); proteinuric gestational hypertension; and toxaemia of pregnancy.  It is a form of high blood pressure (hypertension) that develops in conjunction with water retention (oedema) and/or excess protein in the urine (proteinuria).  Around 3% of all pregnant women suffer from preeclampsia each year and this condition is the principal cause of maternal death in the UK.  Around 10 mothers and 1000 babies die each year as a result of the effects of preeclampsia and the condition is also the most common reason for elective (often early) delivery.  Usually preeclampsia occurs between the 20th week of Pregnancy and the end of the first week postpartum.  The earlier it presents in pregnancy the more threatening it can become.

As I began my research last week I thought this post would be relatively short.  Going back to my 2001 MSc lecture notes there was not a whole lot of dietary/nutrition related evidence to work with.  However, as I began to search through recent medical databases I was pleased and enthralled with the emergence of new information.  The definitive causes of preeclampsia are not known and there are many theories.  Nutritional factors, however, do seem to be at play. 

Keep body weight in check:
Maternal overweight and obesity places women at risk.  A BMI (body mass index) greater than 25 is seen as a risk.  To work out your BMI divide your weight in kg / by your height in metres² (height x height) or use an online BMI calculator e.g. the NHS calculator.  A recent study(2) also shows that gaining a lot of weight during pregnancy may be a risk factor.  This study looked at 34,143 women age 18-34 who were already overweight at the start of their pregnancies.  Gaining more than 15lb during pregnancy was a significant risk factor for the development of preeclampsia and gaining more than 25lb increased the risk further.  The lowest risk of adverse outcomes was for women who gained 6-14lb.

Dietary fibre:
The study(1) mentioned in my opening paragraph was carried out because evidence already exists for the beneficial effects of fibre in reducing hypertension (high blood pressure).  1538 pregnant women were involved in the study and their dietary intake was assessed 3 months before and during early pregnancy.  Women with the highest dietary fibre intake (more than 21g/day) had a significantly reduced risk of preeclampsia when compared to women with the lowest dietary fibre intake (less than 12g/day).  These are important findings, as I have mentioned in previous blog posts the average intake of fibre in the UK is low (around only 12g/day).  The recommended daily intake is currently set at 18g/day in the UK, however for optimal health many experts regard at least 25g/day as necessary. 

This most recent study adds weight to earlier evidence(3) which also found that fibre was associated with a significantly reduced risk of preeclampsia.  The researchers also found that potassium intake was a significant protective factor (I will be discussing potassium intake a blood pressure further on Thursday).  This evidence was interesting as it mentioned specific foodstuffs, with fruits and vegetables being associated with a reduced risk of preeclampsia development (unsurprisingly since vegetables and fruits are great sources of fibre and potassium).

Fruits, Vegetables and Antioxidant Vitamins:
You may be sick of my constant mentioning of vegetables and fruits?!  Well, they really are vitally important to health and I will be writing about them as often as possible!  As indicated above these super foods provide the body with fibre and are fantastic sources of potassium.  In addition to this they are packed full of vitamins, minerals and flavonoids (bioactive plant compounds).  Many of these plant nutrients act as antioxidants in the body.

Antioxidants protect our cells from the damaging effects of highly reactive molecules called free radicals (which cause oxidative stress in the body).  There is mounting evidence that these destructive molecules, together with lowered antioxidant defences, play a significant role in the development of preeclampsia.  The body does produce its own antioxidants but also relies on vitamins, mineral and phytochemicals (including flavonoids) from the diet, especially from colourful vegetables and fruits, for additional valuable supplies.

Dietary antioxidants and supplemental vitamin C and E(4,5), lycopene(6), selenium(7,8) and  multivitamins(9) all appear to have some protective role to play against the development of preeclampsia, although the evidence for supplements is not yet conclusive and further large trials are needed.  The evidence to date certainly seems to suggest an important role for fruit and vegetable consumption during pregnancy, a variety of colourful vegetables and fruits will provide a whole array of vital nutrients to the body.  Selenium is not as widely available in the UK diet, although Brazil nuts are a terrific source. 

In addition to diet you may wish to discuss taking a pregnancy safe multi-vitamin and mineral supplement with your GP, midwife or health professional.

Omega 3 Essential Fatty Acids:
Recent evidence suggests that women with preeclampsia have reduced levels of essential omega 3 fatty acids in their blood(9,10).  Omega 3 fatty acids are vital for the efficient functioning of the immune system.  A lack, or imbalance, of these fatty acids is associated with inflammation in the body.  Inflammatory chemicals (cytokines) have been implicated in the development of and risk for preeclampsia.  Omega 3 fatty acids are essential for optimal foetal development (and are especially important in brain and immune development) and it is important to ensure a regular supply during pregnancy.  I have spoken about these fats extensively in previous posts.  Good dietary sources are oily fish (salmon, trout, mackerel, sardines) and flaxseeds or walnuts for vegetarians/vegans.  Many people in the UK do not eat these foods regularly.  Speaking to your GP or midwife about an omega 3 supplement, a fish oil (providing about 250mg EPA and 250mg DHA per day) or flaxseed oil may be prudent to ensure adequate levels throughout pregnancy and beyond.

At the moment the evidence is preliminary and needs backing up by large, well designed trials and further research.  Personally, I feel that the take home message is that being a normal weight (BMI 19-24), being physically active and having a healthy, nourishing diet rich in fruits, vegetables and essential fats may be protective.....great advice for good health for all of us then!

(1) Qiu et al.  2008.  Dietary fibre intake in early pregnancy and risk of subsequent preeclampsia.  American Journal of Hypertension.  21:903-909 [EPub doi:10.1038/ajh.2008.209 17 July]
(2) Langford A et al.  2008.  Does Gestational Weight Gain Affect the Risk of Adverse Maternal and Infant Outcomes in Overweight Women?  Matern Child Health J.  [Epub ahead of print]
(3) Frederick, I. O., et al.  Dietary fiber, potassium, magnesium and calcium in relation to the risk of preeclampsia.  J Reprod Med.  50(5):332-344, 2005.
(4)Chappell LC et al.  1999.  Effects of antioxidants on the occurrence of preeclampsia in women at increased risk: a randomised trial.  The Lancet.  354:810-816
(5)Chappell  LC et al.  2002.  Vitamin C and E supplementation in women at risk of preeclampsia is associated with changes in indicies of oxidative stress and placental function.  Am J Obstet Gynecol.  187:777-784
(6)Sharma JB et al.  2003.  Effect of lycopene on preeclampsia and intra-uterine growth retardation in primigravids.  Int J Gynaecol Obstet.  81:257-262
(7)Han L & Zhou SM.  1994.  Selenium supplement in the prevention of pregnancy induced hypertension.  Chin Med J.  107:870-871
(8)Rayman et al.  2003.  Low selenium status is associated with the occurrence of the pregnancy disease preeclampsia in women from the United Kingdom.  Am J Obstet Gynecol.  189:1343-1349
(9) Bodnar LM et al.  2006.  Periconceptional multivitamin use reduces the risk of preeclampsia.  Am J Epidemiol.  164:470-477
(10) C et al.  2006.  Erythrocyte omega-3 and omega-6 polyunsaturated fatty acids and preeclampsia risk in Peruvian women.  Arch Gynecol Obstet.  274:97-103
(11)Mehendale S et al.  2008.  Fatty acids, antioxidants, and oxidative stress in pre-eclampsia.  Int J Gynaecol Obstet.  100:134-238

Written by Ani Kowal

Last weekend I had the most delicious artichoke and broad bean salad and it spurred me into thinking about the health benefits of artichoke.  More and more people are taking a supplement of artichoke leaf extract for a variety of reasons.  Artichoke leaf extract is made from the thistle-like leaves at the base of the stem of the Globe Artichoke (botanical name Cynara scolymus) and not from the (very tasty!) artichoke heart that we use in cooking.

Quite a lot of recent research into artichoke leaf extract in the UK has come from the University of Reading and has mostly concentrated on the positive effects of the herb on the digestive system.  Studies have indicated that it may alleviate irritable bowel syndrome(1, 2) and indigestion(3,4). 

However, the latest research, published online last month, has found that artichoke leaf extract is also very effective at reducing cholesterol levels(5).  Many people are now taking statins in order to try and reduce their high cholesterol levels.  Taking steps through diet, exercise and perhaps supplements, before cholesterol levels reach a high could help to reduce the need for drugs (it is my personal opinion that prevention is always better than cure).  This piece of research is important because the study involved healthy people who had only moderately raised blood plasma cholesterol levels (not yet needing drugs) and it was found that the artichoke leaf extract was helpful in reducing their blood cholesterol concentrations.

The trial involved 75 individuals with total plasma cholesterol in the range 6.0–8.0 mmol/l and lasted 12 weeks.  The participants took 1280 mg of a standardised artichoke leaf extract (4 capsules), or a placebo each day.  Plasma total cholesterol decreased significantly in the treatment group (compared to the placebo) by an average of 4.2%.  This may seem like a modest change but it is favourable and certainly significant.

Dr Rafe Bundy, the lead study scientist, is quoted as saying “Reducing cholesterol levels can reduce the risk of developing cardiovascular disease. Our research investigated whether ALE [artichoke leaf extract] could be beneficial to otherwise healthy people who had raised levels of cholesterol but were not yet at a stage where they needed standard medical intervention. ALE may provide another option which people could try over and above a healthy diet in order to help lower plasma cholesterol.”

Artichoke leaf extract may be having an effect via antioxidant action, though the exact mechanism is not clear.  The extract contains a variety of polyphenols/flavonoids (bio-active plant chemicals) such as Caffeic Acid, Chlorogenic Acid and a group of compounds collectively called Caffeoylquiinic Acids (e.g. Cynarin), these are probably the active substances responsible for the beneficial health effects.

Artichoke leaf extract is widely available as a supplement and often supplements are standardised to contain around 15% Chlorogenic Acid and 2-5% Cynarin.  Typically around 600mg-900mg per day is recommended (check the recommended dose on the label) for improved digestion and cholesterol lowering.

(1) Walker AF et al.  2001.  Artichoke leaf extract reduces symptoms of irritable bowel syndrome in a post-marketing surveillance study.  Phytotherapy Research.  15(1):58-61.
(2)Bundy R et al.  2004.  Artichoke leaf extract reduces symptoms of irritable bowel syndrome and improves quality of life in otherwise healthy volunteers suffering from concomitant dyspepsia: a subset analysis.  J Altern Complement Med.  10(4):667-669.
(3)Marakis G et al.  2002.  Artichoke leaf extract reduces mild dyspepsia in an open study.  Phytomedicine.  9(8):694-699.
(4) Holtmann G et al.  2003.  Efficacy of artichoke leaf extract in the treatment of patients with functional dyspepsia: a six-week placebo-controlled, double-
blind, multicentre trial.  Aliment Pharmacol Ther.  18(11-12):1099-1105.
(5)Bundy R et al.  2008.  Artichoke leaf extract (Cynara scolymus) reduces plasma cholesterol in otherwise healthy hypercholesterolemic adults: a randomised double-blind placebo controlled trial. Phytomedicine [Epub ahead of print DOI: 10.1016/j.phymed.2008.03.001 doi:10.1016/j.phymed.2008.03.001]    

Written by Ani Kowal

In Part I I mentioned that UV light can cause damage to the skin and contribute to photo-ageing through the initiation of inflammation.  The long chain omega 3 fatty acids EPA (Eicosapentaenoic acid) and DHA (docosahexaenoic acid) found in oily fish such as salmon, trout, sardines and mackerel as well as the shorter chain alpha-linolenic acid found abundantly in flax seeds acids are used by the body for the production of potent anti-inflammatory chemicals.  Including these omega 3 fatty acids in the diet may help to reduce sun induced inflammation, UVB skin sensitivity and may also help in the prevention of sunburn(1,2,3).

As mentioned in previous posts, omega 3 fatty acids are essential for optimal health for numerous reasons and many of us do not get adequate amounts from our daily diet.  If you are not a regular fish eater, or are vegetarian you may wish to consider taking a fish oil supplement to provide EPA (around 300mg per day) and DHA (around 200mg per day) or a vegetarian flaxseed oil (around 1000mg per day) supplement.  This could be useful to give the skin added natural sun protection and provide the body with a regular source of these essential fats.

Finally I would like to bring your attention to two studies(4,5).  They are of particular interest to me since they looked at cocoa consumption in relation to protection against sunburn.  Really dark chocolate (minimum 85% cocoa solids) is a passion of mine and I tend to indulge in a few squares at least a couple of times a week!  These studies have shown that consumption of flavanol (naturally occurring plant compounds) rich cocoa daily for 12 weeks reduced the risk of sunburn when skin was exposed to UV rays.  The major flavonols to be found in cocoa are called epicatechin and catechin, and it seems as though they are the components within cocoa that are important for boosting sun protection.  The ingestion of high flavanol cocoa led to increases in blood flow to the skin and layers below the skin, and to increases in skin thickness and hydration.

This is not a plug to justify regular chocolate binges (although it does help me to feel better about my dark chocolate habit)!  The cocoa used in these studies, and other studies that link cocoa to health benefits such as lowered risk of heart disease, was high flavanol cocoa and only a very small amount was used daily (around 350mg).  I am fond of drinking black cocoa but it is an acquired taste, as is the bitter high % cocoa chocolate that I so adore.  Sugary, sweet milk chocolate won’t provide the health benefits discussed (sorry to be the bearer of sad news!).  Flavonoids in general are found abundantly in fruits and vegetables, which, as mentioned in part I are important in sun protection through their provision of antioxidants.  Vegetables and fruit should form the core of a healthy diet and getting a good variety will give the body many of the nutrients that are needed for optimal health.

Obviously avoiding sun burn is exceptionally important, however, a slowly-acquired sun-tan may prevent against adverse effects of sun exposure in those who naturally tan easily.  Sun-sensitive individuals (those with fair skin and who burn easily) need to be careful as they have a higher risk for skin cancers.  Seeking shade, wearing a hat, adequate clothing and avoiding prolonged sunbathing is always advisable.  Sunscreens may also help but the ability of sunscreen to delay sunburn encourages many people to stay out in the sun for long periods of time and their skin (and health) may be negatively affected by this prolonged exposure. 

Please be sensible in the sun! 

(1) Rhodes LE et al.  1995.  Dietary fish oil reduces basal and ultraviolet B-generated PGE2 levels in skin and increases the threshold to provocation of polymorphic light eruption.  Journal of Investigative Dermatology.  105(4):532-535.
(2) Rhodes LE et al.  2003.  Effect of eicosapentaenoic acid, an omega-3 polyunsaturated fatty acid, on UVR-related cancer risk in humans. An assessment of early genotoxic markers.  Carcinogenesis.  24(5):919-925.
 (3) Takemura N et al.  2002.  Dietary, but not topical, alpha-linolenic acid suppresses UVB-induced skin injury in hairless mice when compared with linoleic acids.  Photochem Photobiol.  76(6):657-663.
(4) Heinrich U et al.  2006.  Long-term ingestion of high flavanol cocoa provides photoprotection against UV-induced erythema and improves skin condition in women.  Journal of Nutrition.  136(6):1565-1569.
(5) Neukam K et al.  2007.  Consumption of flavanol-rich cocoa acutely increases microcirculation in human skin.  Eur J Nutr.  46: 53-56

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