The links between diet and cancer are widely researched.  The World Cancer Research Fund UK (WCRF UK) estimate that lifestyle factors such as being overweight, eating an unhealthy diet and being inactive are responsible for about a third of all cancers in developed countries (1).  The WCRF UK are a charity committed to cancer prevention.

A recently published study (2) has found a significant link between eating a diet high in carotenoid rich fruits and vegetables and a reduction in the risk of breast cancer in premenopausal women.

Carotenoids such as alpha and beta carotene, lutein and zeaxanthin are a family of over 700 naturally occurring yellow, red, orange and dark green pigments found in vegetables and fruits.  Good sources include carrots, sweet potatoes, tomatoes, squash, peppers, cantaloupe melons, nectarines, papaya, mango and dark green vegetables such as spinach, kale, watercress and asparagus.  Introducing a good mix of these fruits and vegetables on a regular basis in the diet will help keep carotenoid levels in the body high.

The study (2) involved 5,707 women with invasive breast cancer (2,363 premenopausal women and 3,516 postmenopausal women) and 6,389 individuals with no breast cancer, control subjects (2,594 premenopausal women and 3,516 postmenopausal women).  In an interview, these women were asked about their intake of carotenoid rich fruits and vegetables.  The researchers found that pre-menopausal women eating high intakes of vitamin A, beta-carotene, alpha-carotene, lutein and zeaxanthin appeared to have a reduced risk of breast cancer.  Eating at least two servings of carotenoid-rich vegetables each day was associated with around a 17% reduced risk of breast cancer.  As an association study the results are positive but further studies would be necessary before any firm conclusions could be drawn about the effect of dietary carotenoids on cancer risk. 

Carotenoids may be acting to prevent cancer via different means.  Carotenoids have been shown to interfere with oestrogen (hormone) signalling which may explain why their cancer-preventing effects would be limited to premenopausal women.  In addition to this, carotenoids act as antioxidants in the body and antioxidants have been linked to cancer prevention.  Antioxidants prevent damage to the body cells by naturally occurring unstable oxygen molecules, known as free radicals.  Antioxidants may help to ‘quench’ or mop-up the destructive free radical molecules and therefore protect against cell-damage (which could lead to cancer formation).

Absorption of carotenoids from foods into the body is greatly affected by fat.  Without a fat source carotenoids are not easily absorbed.  Fat acts as a carrier for these nutrients to allow them passage from the gut into our blood and bodily cells.  This is not a suggestion to drown your vegetables or salads in gallons of oil, however, I am a firm believer in using small amounts of olive oil in dressings and cooking.  Including some nuts, seeds or olives in salads may also be helpful in order to gain maximum absorption of these important nutrients. 

(1)WCRF/AICR.  2009.  Policy and action for cancer prevention.  Food, nutrition and physical activity: a global perspective.  Washington DC: AICR, 2009.
(2) Mignone LI et al.  2009.  Dietary carotenoids and the risk of invasive breast cancer.  International Journal of Cancer.  124:2929-2937
Written by Ani Kowal

Over the years there has been debate as to whether oral contraceptive use in women leads to depletion of certain nutrients in the body.  There is some evidence that oral contraceptives may reduce levels of Vitamin B1, B2, B6, folate, vitamin C, vitamin E, zinc, magnesium and calcium.  However, many of these studies were small and carried out over 20 years ago with very little follow up since.  During this time the contraceptive pill has changed dramatically and now contains lower doses of hormones.  Women who are eating a healthy, nutrient-rich diet probably gain enough vitamins and minerals to counteract any deficit but many women in the UK are not reaching the minimum 5 portions per day of vegetables and fruits and many also do not gain enough magnesium and other minerals through their diets. 
 

The early studies do warrant attention and I was interested to find two more recent papers (1,2) which point to the importance of being nutrient-aware when taking oral contraceptives.  These two studies look at how oral contraceptives may have an effect on the antioxidant levels in the body.  

I have written about dietary antioxidants in many previous blog posts.  Antioxidant intakes and bodily status has been linked to a reduction in the risk of many conditions raging from cancer to heart disease, dementia and arthritis.  One of the reasons why fruit and vegetables are so important in our diets is because they provide many antioxidant nutrients, such as carotenoids, vitamins C and E and various antioxidant bioflavonoids (bioactive plant chemicals). 

Anitoxidants help to prevent damage to cells in our body by mopping-up destructive unstable oxygen molecules known as 'free radicals', these free radicals create what is known as oxidative stress in the body.  There is mounting evidence that these destructive molecules, together with lowered bodily antioxidant defences, play a significant role in the development and aggravation of many diseases and health problems.  The body does produce its own antioxidants but also relies on vitamins, mineral and phytochemicals (bioactive plant chemical) from the diet, especially from colourful vegetables and fruits, for additional valuable supplies.

It has been thought for some time that oral contraceptive use may lead to increased oxidative stress in women.  One study (1) which took place in 2007 included 209 healthy women aged 40-48 years.  The oxidative stress status of the women was studied, this included an analysis of antioxidant levels, trace minerals and three markers of oxidative damage to fats (lipids).  Among the 209 women 23% used oral contraception, 57% did not use contraception and 20% used hormonal and copper intrauterine devices (IUD). 

Results showed(1) that women using oral contraception had significantly higher oxidative damage to lipids (lipid peroxidation) compared to the other 2 groups of women.  Lipid peroxidation has been linked to heart disease.  Oral contraceptive users also had significantly lower blood plasma levels of several antioxidants such as beta-carotene and gamma-tocopherol (a form of vitamin E).  The study scientists checked their data and confirm that modifications in plasma beta-carotene levels could not be attributed to dietary differences between the three groups.  The beta-carotene levels were 39-50% lower in the oral contraceptive users compared to the other groups of women.  The authors conclude that these lowered levels of antioxidants and increased signs of bodily oxidative stress could represent a potential cardiovascular risk factor for these women.

Another study (2) looked to examine the influence of oral contraceptive use on blood serum levels of antioxidants.  The study was a very small, preliminary trial in pre-menopausal women.  The researchers found that oral contraceptive use significantly decreased coenzyme Q10 (an antioxidant) and alpha-tocopherol (vitamin E) levels.  The authors conclude that further studies are needed to investigate the potential role of oral contraceptives on oxidative stress in women.

Coenzyme Q10 is naturally produced by the body and was first isolated in 1957, it is essential for energy production in all bodily cells and also acts as an antioxidant in the body.  Coenzyme Q10 itself is found in many foods but is particularly concentrated in nuts and oils.  The body does produce this nutrient naturally and does not rely on external sources.  In order to produce CoQ10 we require various essential cofactors.  These include a variety of vitamins especially of the B group (Folic Acid, Vitamin B2, The Niacinamide form of Vitamin B3, Vitamin B5,Vitamin B6, Vitamin B12) and Vitamin C .  Hence a healthy diet rich in fruits, vegetables, wholegrain cereals and lean proteins will aid the natural production of this coenzyme and help to keep our circulating levels high.

The results of these studies need backing up by further larger clinical trials but could indicate the consideration of antioxidant supplementation for women taking oral contraceptives. 

Eating a healthy diet low in processed and refined foods and rich in vegetables, fruits, nuts/seeds, beans and pulses, lean meats, fish (especially oily varieties), wholegrains and healthy fats is the best way to ensure that your body gets plenty of vitamins, minerals and antioxidants.  If you feel that your diet is regularly falling short then you could consider taking a broad spectrum multivitamin and mineral supplement – but remember that a supplement cannot be considered as an alternative for a healthy diet.

1.Chapelle JP et al.  2007.  Effect of different contraceptive methods on the oxidative stress status in women aged 40 48 years from the ELAN study in the province of Liege, Belgium.  Hum Reprod.  22:2335-2343
2. Palan PR et al.  2006.  Effects of menstrual cycle and oral contraceptive use on serum levels of lipid-soluble antioxidants.  Am J Obstet Gynecol.  194:e35-38

Written by Ani Kowal

A recently published small study (1) has found that men with prostate cancer who consumed an active green tea supplement had significant reductions in biological-markers predictive of prostate cancer progression.

Green tea has become an incredibly popular drink and supplement and an increasing number of studies are being published with regards its health benefits.  The number of current human studies investigating the relationship between green tea and prostate cancer is small.  This study (1) was preliminary but informative.  It involved just 26 men aged 41-72 years old who were diagnosed with prostate cancer and due to undergo radical prostatectomy.  The trial looked to determine the effects of short-term supplementation with the active compounds found in green tea on biological-markers in patients diagnosed with prostate cancer.  These biomarkers [technically looking at hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF) and prostate specific antigen (PSA)] are good prognostic indicators of prostate cancer progression.

The men involved in the study were given 4 green tea capsules for an average of 34 days prior to surgery.  The 4 capsules provided the equivalent of around 12 cups of normally brewed green tea.  Results showed that there was a significant reduction in blood serum levels of the biological-markers of prostate cancer after treatment with the green tea capsules.  Some of the patients had reductions in the biomarker levels of more than 30%.  The supplements had no effect on liver function, which was used as a measure of toxicity.

The supplement used contained 1.3g tea polyphenols, bioactive plant nutrients, that are found naturally in green tea: 800 mg of epigallocatechin-3-gallate (EGCG) and lesser amounts of epicatechin, epigallocatechin, and epicatechin-3-gallate.  Green tea supplements often have these polyphenols listed as active 'ingredients'.

In a press release(2) one of the authors commented: "These studies are just the beginning and a lot of work remains to be done, however, we think that the use of tea polyphenols alone or in combination with other compounds currently used for cancer therapy should be explored as an approach to prevent cancer progression and recurrence". 

In the same press release(2) William G. Nelson, V., M.D., Ph.D., professor of oncology, urology and pharmacology at the Johns Hopkins Kimmel Cancer Center, said that he believed the reduced blood serum biomarkers of prostate cancer may be attributable to some sort of benefit relating to green tea components "Unfortunately, this trial was not a randomized trial, which would have been needed to be more sure that the observed changes were truly attributable to the green tea components and not to some other lifestyle change (better diet, taking vitamins, etc.) men undertook in preparation for surgery,". However, "this trial is provocative enough to consider a more substantial randomized trial."

The researchers of this study are currently conducting a comparable trial among patients with breast cancer.

For general information about nutrition and prostate health please read my previous blog posts on the subject (Prostate health Part I and II).  For more information on prostate cancer please visit the Prostate Cancer Care website.

The World Cancer Research Fund (WCRF) estimate that lifestyle factors such as being overweight, eating an unhealthy diet and being inactive are responsible for about a third of all cancers in developed countries (3).  Please visit the WCRF website for information related to diet and cancer prevention.

1. McLarty J et al.  2009.  Tea Polyphenols Decrease Serum Levels of Prostate-Specific Antigen, Hepatocyte Growth Factor, and Vascular Endothelial Growth Factor in Prostate Cancer Patients and Inhibit Production of Hepatocyte Growth Factor and Vascular Endothelial Growth Factor In vitro.  Cancer Prevention Research, 10.1158/1940-6207.CAPR-08-0167.  Published online June 19
2.Sciencedaily.com press release.  American Association for Cancer Research (2009, June 22). Green Tea May Slow Prostate Cancer Progression. ScienceDaily. Retrieved June 23, 2009, from http://www.sciencedaily.com¬ /releases/2009/06/090619112329.htm
(3) WCRF/AICR.  2009.  Policy and action for cancer prevention.  Food, nutrition and physical activity: a global perspective.  Washington DC: AICR, 2009.

Written by Ani Kowal

Regular readers of my blog will have realised by now that I have a great interest in Omega 3 fatty acids.  Research suggests that these essential fats play a role in the prevention of several diseases ranging from heart disease to cancer, stroke, diabetes, arthritis, asthma, osteoporosis, mood disorders (including depression), eye diseases and many more (including most conditions with a link to inflammation).  A major voice for the importance of these fats is Artemis Simopoulos MD.  Dr Simopoulos is president of The Centre for Genetics, Nutrition and Health and a member of the board of directors of the American Association for World Health.  Since 1984 her research has been largely dedicated to the evolutionary aspects of diet, the omega-6:omega-3 ratio of the diet and the importance of omega-3 fatty acids for health.

In an interview (1) Dr Simopoulos said that one of the biggest food myths today is that you have to give up fat to lose weight and enjoy health.  A statement I wholeheartedly agree with.  Of course, not all fats are the same and today I want to discuss the virtues of omega 3 fatty acids.  These can be found in fish, especially oily fish such as salmon, trout, mackerel and sardines, seafood, as well as flaxseeds, walnuts and green leafy vegetables.  Meat and eggs in the UK do not contain large amounts of omega 3 fatty acids anymore since our farming methods have drastically changed over the years, this has contributed to the huge decline in our intakes of this vital fat.  Grass reared animals will have better omega 3 fatty acid levels, but nowhere near as high as in the past when animals were less intensively reared.

Dr Simopoulous has written many research and review papers about the importance of omega 3 fatty acids, and I am going to use some information from a fairy recent one (2) to provide the basis for this post.  She has also written many books including ‘The Omega Plan’.

It is thought that humans evolved on a diet that was very rich in essential omega-3 fatty acids, and a ratio of omega-6:omega-3 fatty acids of about 1:1 (or at most 2:1).  Currently the western diet has an imbalanced ratio of about 15:1 !!  This represents a huge shift and a relative ‘deficiency’ in omega-3 fats.  The excessive amounts of omega-6 fats and the very high omega-6:omega-3 ratio today is thought to be a major contributor to many of the diseases listed above.  A diet rich in omega-3 fatty acids and with a lower omega-6:omega-3 ratio is highly desirable for reducing the risk of many of the chronic diseases in the Western world.  Low intakes of omega-3 fats and higher intakes of omega-6 fats can lead to an increase in inflammation in the body since omega-3 fats are used by the body to make potent anti-inflammatory chemicals whereas too much omega-6 can lead to the production of pro-inflammatory chemicals by the body.

Nutrition can affect our genes and hence have an influence on disease.  Over the last 10,000 years our diet has drastically changed, especially over the last 150 years, to almost unrecognisable degrees in most people.  However, genetically we have not changed much (our DNA is much the same).  Our genes today are incredibly similar to those of our ancestors who lived around 40,000 years ago.  Our diet now is so very different, particularly in the type of fats we eat, and in the antioxidant nutrient content of our foods (antioxidants are found abundantly in vegetables and fruits) and this is surely affecting our health.

The review paper(2) details the ways in which our diet differs from that of our pre-industrial ancestors:
1. We have an increase in energy intake and a decrease in energy expenditure
2. Our diets are richer in saturated fat, omega-6 fats and trans fats and lower in omega-3 fats
3. We do not eat as much complex carbohydrates and fibre
4. We eat a huge amount more cereal grains and a reduced amount of fruits and vegetables
5. We eat less protein, antioxidants and calcium

Omega-6 fatty acids are found abundantly in our diets – most seeds, nuts, vegetable fats (vegetable seed oils) are omega 6 rich.  By contrast our diets are generally low in omega-3 fats: short chain omega-3 fats (alpha linolenic acid) are found in flaxseeds and walnuts (as well as chia and perilla seeds) and in their longer chain forms (EPA eicosapentaenoic acid and DHA docosahexaenoic acid) are found in oily fish.  The long chain omega-3 fats seem particularly important for our health and are found in concentrated amounts in the human brain.  The body can use the short chain omega-3 fats from the diet to form the longer-chain EPA and DHA forms but the process is far from efficient.  EPA and DHA are used by the body to produce the biological chemicals which have potent anti-inflammatory effects.  As a nutritionist I feel that it is essential we work toward increasing the intake of omega-3 and decreasing the intake of omega-6 fats in our diets in order to redress the omega-6:omega-3 balance (2).

If you feel that you do not eat oily fish regularly (you may be vegetarian or vegan or example), at least twice per week, then you may wish to consider taking an omega-3 fish oil supplement that provides around 250-300mg EPA and 250-350mg DHA per day.  Choose supplements that also contain vitamin E or another antioxidant since these protect the oil from degradation.  For vegans and vegetarian flaxseeds and walnuts represent good sources of the short chain omega-3 fatty acid – however, a flaxseed oil supplement that provides around 500-1000mg alpha-linolenic acid daily is worth considering.  Again, choose a supplement that contains a protective antioxidant.  There are now some vegan EPA and DHA supplements being produced from algae.  They are obtainable from only a few sources and can be expensive but their popularity and availability are rising and they are worth considering.

Dr Simopoulos offers 7 general dietary guidelines(1):
1.Enrich your diet with omega-3 fatty acids with cold-water fish, flax and walnut oil
2.Use canola, olive and flax oils as your primary oils
3.Eat seven or more servings of fruits and vegetables each day
4.Eat more peas, beans and nuts
5.Eat less saturated fat
6.Avoid oils high in omega-6 fatty acids such as corn, safflower, peanut, soyabean, sunflower and cottonseed oils – avoid products made from these oils
7.Avoid trans-fatty acids (found in many processed foods.  Trans fatty acids are used in the prepared food industry to prolong the shelf life of baked goods like biscuits).

In addition to this I would add that a healthy diet is one that contains minimal amounts of processed and refined foods.  Think natural! 

(1)http://www.1stvitality.co.uk/pdfs/Barleans_GB_dr_Simopoulos.pdf
(2)Simopoulos AP.  2008.  The importance of the omega-6/omega-3 fatty acid ratio in cardiovascular and other chronic diseases.  Exp Biol Med (Maywood).  233:674-688

Written by Ani Kowal

There seems to be a run of research being released at the moment looking at pregnancy and fertility related issues, as you can see from my recent blog posts.  In a recent review paper (1) researchers have estimated that 1.5million fewer babies would be born at low birth weights every year if all pregnant women, worldwide, took vitamin and mineral supplements. 

The lead researcher of the study, Dr Prakesh Shah, stated in a press release (2) that women should start taking vitamin and mineral supplements “as soon as they know they are pregnant”.  Compared with women who took a placebo, women who took multi-nutrient supplements were 19% less likely to have a low birth weight baby.

Low birth weight infants, those born weighing less than 2.5 kilograms (about 5.5 pounds), face a greater risk of health problems that may extend into adulthood. They tend to be more vulnerable to infections during infancy and childhood and may be more likely to have developmental problems in childhood.  As adults they may be at greater risk of diabetes and high blood pressure.  This study (1) found that “Prenatal multimicronutrient supplementation was associated with a significantly reduced risk of low birth weight and with improved birth weight when compared with iron–folic acid supplementation”.

Currently, the World Health Organization (WHO) recommends supplementation with folic acid and iron during pregnancy.  However there have been numerous studies showing that a number of different vitamins/minerals may be necessary in early pregnancy for the best outcomes for mother and baby.  In this current study (1) when compared with women taking iron and folic acid only, the researchers found the multi-supplement users had a 17% risk of having a low birth weight baby.  Babies born to women taking multimicronutrient supplements weighed 54 grams more, on average, than babies born to women taking iron and folic acid alone.  The authors of the study suggest that the WHO could consider revisiting their guidelines to recommend multi-nutrient supplements, not just iron and folic acid, for all pregnant women.

The research is limited by the fact that it is a review study of already published data, not an intervention trial.  In addition to this the studies included in the review varied with regards timing, duration, composition of micronutrients, and characteristics of the study populations.  In populations where under-nutrition is common the multi-nutrient supplement may be more helpful than in populations where nutrient rich diets are eaten.  However there is a growing increase in teenage pregnancy here in the UK and often these children are not following a healthy diet and may well be lacking in a number of vitamins and minerals.  In addition to this my previous posts have shown that many nutrients in early and pre pregnancy are associated with better health in mothers and children in Western populations, so it does seem that multi-nutrient supplements could be important for all pregnant women.

Supplements designed especially for pregnant women are widely available, however it is always a good idea to check with your doctor or midwife before taking any supplements during pregnancy.  As mentioned last week – a healthy balanced diet also very important at all times, but especially during pregnancy.

(1)Prakesh S. Shah et al.  2009.   Effects of prenatal multimicronutrient supplementation on pregnancy outcomes: a meta-analysis.  CMAJ.  June 9, 180 (12). doi:10.1503/cmaj.081777.
(2)Anne Harding.  Multivitamins best for preventing low birth weight.  08/06/2009.  Reuters Health.  http://www.reutershealth.com/archive/2009/06/08/eline/links/20090608elin005.html
(3) Canadian Medical Association Journal (2009, June 8). Multivitamins In Pregnancy Reduce Risk Of Low Birth Weights. ScienceDaily. Retrieved June 9, 2009, from http://www.sciencedaily.com/releases/2009/06/090608182549.htm

(4)Bhutta ZA & Haider BA.  2009.  Prenatal micronutrient supplementation: Are we there yet?  Commentary.  CMAJ • June 9, 2009; 180 (12). doi:10.1503/cmaj.090652

Written by Ani Kowal

Diet and its impact on male fertility has long been discussed and debated among scientific, medical and health professionals.  I first started to look at the link between what we eat and fertility, in men and women, whilst studying for my MSc.  The research has been steadily growing over the years and it seems likely that diet does impact fertility.

A group of Spanish researchers have published two (1,2) studies this year which look at the link between diet and semen quality in men.  The studies seem to suggest that dietary antioxidant nutrients play a key role in the prevention of damage to sperm. 

I have written about dietary antioxidants in many previous blog posts.  They have been linked to a reduction in the risk of many conditions raging from cancer to heart disease, dementia and arthritis.  One of the reasons why fruit and vegetables are so important in our diets is because they provide many antioxidant nutrients, such as vitamins C and E and various antioxidant bioflavonoids (bioactive plant chemicals). 

Anitoxidants help to prevent damage to cells in our body (including sperm cells) by mopping-up destructive unstable oxygen molecules known as 'free radicals', these free radicals create what is known as oxidative stress in the body.  There is mounting evidence that these destructive molecules, together with lowered bodily antioxidant defences, play a significant role in the development and aggravation of many diseases and health problems.  The body does produce its own antioxidants but also relies on vitamins, mineral and phytochemicals (bioactive plant chemical) from the diet, especially from colourful vegetables and fruits, for additional valuable supplies.
 

In the first research study (1) the authors found that men who ate large amounts of meat (especially processed meat) and full fat dairy products had poorer quality sperm than those who ate more fruit, vegetables and reduced fat dairy products.  The study was a case-control study in which 30 men with poor semen quality (cases) were compared to 31 men with normal sperm quality (controls).  The investigators recorded the dietary habits and food consumption of the men using a specialised food frequency questionnaire.  The authors conclude that “Frequent intake of [lipophilic] foods like meat products or milk may negatively affect semen quality in humans, whereas some fruits or vegetables may maintain or improve semen quality”.  This study points towards associations between diet and fertility.  It is certainly plausible that a healthy diet and lifestyle can impact upon the health of semen. 

The second study(2) published by the same group of scientists this year was set up in order to compare the specific nutrient intakes between 30 men with normal sperm quality and 31 men with poor sperm quality.  Dietary habits and nutrient consumption were recorded using a food frequency questionnaire.  The analysis found that control subjects, the men with normal sperm quality, had a significantly higher intake of carbohydrates, fibre, folate, vitamin C, and lycopene and lower intakes of proteins and total fat than men with poor sperm quality.  The authors conclude that “A low intake of antioxidant nutrients was associated with a poor semen quality in this case-control study of Spanish men attending infertility clinics”.

Vegetables and fruits are full of antioxidant nutrients and flavonoids which may well be protecting the sperm from damage.  The lead author of the paper, Jamie Mendiola, said in a press release(3): “In this study, we have found that people who consume more fruits and vegetables are ingesting more antioxidants, and this is the important point", "We saw that, among the couples with fertility problems coming to the clinic, the men with good semen quality ate more vegetables and fruit (more vitamins, folic acid and fibre and less proteins and fats) than those men with low seminal quality".  "A healthy diet is not only a good way of avoiding illness, but could also have an impact on improving seminal quality.  What we still do not understand is the difference between taking these vitamins naturally and in the form of supplements”.

The authors are going to continue researching this topic in another study and are particularly going to investigate the role that supplements may have on sperm quality.  Obviously I am a great advocate of healthy eating and the basis of any healthy diet is an abundance of vegetables, fruits, healthy fats from nuts/seeds/oily fish, protein from unprocessed lean meats, pulses, beans and unprocessed/unrefined wholegrain carbohydrates.  For individuals who feel they often lack the five or more recommended portions of vegetables and fruits daily may wish to consider taking a good quality multi-vitamin and mineral supplement in order to provide for any nutrient shortfalls, however supplements should never be seen as an alternative to healthy living

(1)Mendiola J et al.  2009. Food intake and its relationship with semen quality: a case-control study.  Fertil Steril.  91:812-818
(2)Mendiola et al. A low intake of antioxidant nutrients is associated with poor semen quality in patients attending fertility clinics. Fertility and Sterility, May 2009; DOI: 10.1016/j.fertnstert.2008.10.075
(3)Plataforma SINC (2009, June 3). Semen Quality May Depend Upon Antioxidants In Man's Diet. ScienceDaily. Retrieved June 4, 2009, from http://www.sciencedaily.com¬ /releases/2009/06/090602083727.htm

Written by Ani Kowal

Since I started the week with a focus on the pregnancy related condition preeclampsia I thought it was a good time to mention a recent study (1) that looked at vitamin supplement use in pregnancy to see if there was any association with the risk of having a miscarriage.  

In this study(1), the authors wanted to look at the relationship between use of prenatal vitamins in early pregnancy and the risk of miscarriage.  4,752 women in the US were involved and individual data about vitamin use was collected at a first-trimester interview.  Approximately 95% of participants reported use of vitamins during early pregnancy and a total of 524 women had a miscarriage.  Any use of vitamins during pregnancy was associated with a reduced risk of miscarriage when compared to women who did not take any vitamins.  The researchers found that the risk for miscarriage was 57% lower among women who took vitamins, compared to those who did not.

These results suggest that taking vitamins before pregnancy and during early pregnancy is associated with a reduced risk for miscarriage.  However the study is far from conclusive.  It may well be that women who take vitamins also tend to be more aware of the factors considered important for health and may tend to lead generally healthier lifestyles when compared to women who do not take vitamins, other confounding factors may also be involved.  Further studies are necessary before firm conclusions can be drawn regarding the effects of supplements on miscarriage risk.   

In a press release (2) the lead study author said  "Because miscarriage occurs very early in pregnancy, it is important for women of reproductive age, who may become pregnant, to eat a balanced diet and use vitamins."  Recently I have written a lot about the links between various nutrients such as folic acid, vitamin B12, vitamin D and multivitamins in early pregnancy and pre pregnancy and an apparent reduced risk of various pregnancy related issues in the mother and baby.  Pre-pregnancy and pregnancy is a very important time for healthy living and healthy eating. 

If you are planning a pregnancy eating plenty of vegetables, fruits, nuts/seeds, beans/pulses, fish (especially oily fish such as salmon, trout and mackerel), unprocessed meats and unprocessed/unrefined wholegrains will help to provide an abundance of vitamins, minerals, flavonoids (bioactive plant chemicals),fibre, protein, healthy fats and energy for you and your baby.  If you feel concerned that you may not be eating a consistently nutritious diet then you may wish to consider taking a food-state multi-nutrient supplement specifically designed for use during pregnancy.  An omega 3 supplement could also be helpful, especially if you do not regularly eat oily fish (at least twice a week) or nuts/seeds.  Before deciding to take any supplement during pregnancy please discuss your thoughts with a GP, nurse or midwife.  For information about miscarriage and support please visit the Miscarriage Association charity website. 

(1)Hasan R et al.  2009.  Self-reported vitamin supplementation in early pregnancy and risk of miscarriage.  Am J Epidemiol. 169(11):1312-8.
(2)Reuters Health press release .  Vitamin Sypplements may lessen miscarriage risk.  Joene Hendry.  Health eLine 05/06/2009.  http://www.reutershealth.com/archive/2009/06/05/eline/links/20090605elin006.html

Written by Ani Kowal

In August last year I wrote about the possible role of a diet in the prevention of preeclampsia with specific reference to maintaining a healthy body weight, dietary fibre, fruits, vegetables, antioxidant vitamins and omega 3 fatty acids.  I was very interested to read a recently published study (1) which has found that regular multivitamin use in the very early period of pregnancy is associated with a reduced risk of preeclampsia in normal weight, but not overweight, women.

Preeclampsia is a very serious condition.  Around 3% of all pregnant women suffer from preeclampsia each year and it is the principal cause of maternal death in the UK.  Preeclampsia is a form of high blood pressure that develops in conjunction with water retention and/or excess protein in the urine.  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.  For more information please visit the Action On Pre-eclampsia charity website.

The study (1) looked at a large group of Danish women, over 28,000 women, between the years 1997-2003 who reported multivitamin supplement use during a 12 week periconceptional period, the very earliest weeks of pregnancy, measured as 4 weeks prior to and 8 weeks after the last menstrual period.  The researchers then looked to see whether the frequency and timing of multivitamin use was associated with preeclampsia risk - regular use of multivitamins in the periconceptual period was related to a reduced risk of preeclampsia among normal-weight women.  Compared with women who did not use multivitamins, regular multivitamin users with the same body mass index (of 22) had a 20% reduced risk of preeclampisa.  In addition, regular use of multivitamins in the post-conception period only seemed to be associated with a reduced risk of preeclampsia in women with a BMI less than 25 (a healthy BMI is usually measured at 18.5-20).  This is only an association study, it does not show cause and effect and further controlled supplement trials are certainly necessary before any firm conclusions can be drawn.  However, the data does indicate that multivitamins in early pregnancy may be useful in preventing preeclampsia in some women. 

BMI (Body Mass Index) is a measure often used for healthy weight, it is worked out as weight divided by height squared.  To check your own BMI you may find it useful to visit the Food Standards Agency website where an online BMI calculator can be found.

In previous weeks I have talked about early use of folic acid and vitamin B12 being important for a number of pregnancy related conditions so a multi-nutrient supplement could be a way of ensuring a good intake of a variety of nutrients linked to improved health of both the mother and child during pregnancy.  Many multi-nutrient preparations are available specifically for use by pregnant women but please always check with a doctor or health professional before starting supplementation if you are planning a pregnancy.  It is also important for me to mention that supplements cannot be seen as an alternative to a healthy diet and lifestyle.  Pregnant women really do need to ensure that they are eating well in order to give their baby the best start in life.  A healthy diet, low in processed and refined foods and  rich in vegetables, fruits, oily fish, lean unprocessed meats and fish, nuts/seeds, beans, pulses and unrefined/unprocessed wholegrains will go far in providing the body with an abundance of vitamins, minerals, flavonoids (bioactive plant chemicals) and essential fats.

Since I seem to be mentioning Vitamin D quite regularly I thought I would briefly include a study(2) that I came across very recently.  The researchers wanted to see if intake of vitamin D during pregnancy was associated with preeclampsia risk.  The study involved 23,423 Norwegian pregnant women who had not previously had children.

Participating women filled in questionnaires at week 15, 22, and 30 of pregnancy.  From these questionnaires nutrient intakes were calculated from food and dietary supplements.  Data showed that women with the lowest levels of vitamin D were more at risk of developing preeclampsia than women with the highest levels.  When the data was analysed to considering only the intake of vitamin D from supplements, the scientists found a 27% reduction in risk of preeclampsia for women taking 10-15 micrograms per day compared with women taking no supplements. No association was found between intake of vitamin D from the diet alone and the occurrence of preeclampsia.   The report concludes (2) that “These findings are consistent with other reports of a protective effect of vitamin D on preeclampsia development”.  However, the authors make an interesting point: Vitamin D intake is highly correlated with the intake of long chain omega 3 fatty acids in the Norwegian diet and further research is needed to disentangle the separate effects of these nutrients.  Oily fish are a great source of omega 3 fatty acids and one of the few good dietary sources of vitamin D.

As mentioned in many blog posts on Vitamin D many of us in the UK do not achieve good levels from the diet or from sunlight exposure. If you rarely get out into the sun, you may wish to consider a vitamin D supplement which provides around 12mcg/day (around 500iu a day).  Such a supplement may be particularly useful during the autumn and winter months.  Before considering any supplementation during pregnancy please check with your doctor and be aware that multi-vitamin and mineral supplement may already contain ample amounts of vitamin D. 

(1)Catov JM et al.  2009.  Association of Periconceptional Multivitamin Use With Reduced Risk of Preeclampsia Among Normal-Weight Women in the Danish National Birth Cohort.  American Journal of Epidemiology 2009 169(11):1304-1311; doi:10.1093/aje/kwp052
(2) Haugen M et al.  2009.  Vitamin D supplementation and reduced risk of preeclampsia in nulliparous women.  Epidemiology.  [Epub ahead of print]

Written by Ani Kowal