Fertility & Nutrition: What Does The Research Say?
Article by Ellie Morris
Fertility simply refers to the ability to produce offspring. For some getting pregnant may be more difficult than others and there are numerous factors in our day to day lives that can influence an individual’s fertility. Whilst we do not have control over some of these, such as our age, there are other positive lifestyle choices we can make which may help promote fertility. Along with reduced stress levels, having a healthy weight, plenty of rest and regular movement, our diets can play a very important role in fertility. Whilst there is no ‘right way’ to eat during pregnancy as we are all unique, over the years more and more research has been done to try to better understand how what we eat can impact both men and women’s chances of conceiving. Rhiannon is delighted to be bringing out her latest book, Deliciously Healthy Pregnancy, which is based on the latest scientific research and backed-up with practical advice and recipes that expectant mums can trust, to support you and your family.
Folate & ovarian reserves
It’s well-known that when trying to conceive, particularly in the 3 months prior to conception, and in the first 12 weeks of pregnancy it’s important that women consume dietary folate, as well as a high quality folic acid supplement, such as Rhitrition+. Folate, also known as vitamin B9, is found in leafy green vegetables such as broccoli, spinach, and kale and legumes like kidney beans and chickpeas, and can help improve the quality and maturation of eggs, and importantly reduce the risk of neural tube defects such as Spina Bifida in unborn babies. During the preconception period and in early pregnancy, in the UK, it is recommended by the NHS that a 400mcg folic acid supplement is taken alongside a healthy and balanced diet.
In addition to this a higher intake of folate, and in particular folic acid supplements, has also been linked to an improved ovarian reserve in women. The ovarian reserve relates to the reproductive potential of women’s ovaries based on the number and quality of eggs, where a higher reserve suggests better reproductive potential.
Omega-3 FA’s may support embryo quality and outcomes of IVF
Omega-3 fatty acids are a type of polyunsaturated fat that are an important part of our diets. We cannot produce omega-3 fatty acids within our bodies so ensuring that we consume enough from foods like oily fish, flaxseeds, and walnuts, alongside a balanced diet is essential for the optimal functioning of our bodies. Omega-3 fatty acids play a key role in our hormone production and studies have shown that an adequate consumption may be linked to a reduced incidence of certain diseases such as heart disease, poor brain health, and diabetes. Recently, evidence has also suggested these omega-3 fatty acids may be useful for improving embryo quality and pregnancy outcomes in women who are undergoing assisted reproductive techniques. However, this research is very much in its infancy and more studies with higher scientific rigour are needed to fully understand the effect of omega-3 fatty acids on fertility in both men and women.
If you would like to read more about omega-3 fatty acids and their effects on the body then you may find this blog useful.
Probiotics & PCOS
We know that having good gut health is beneficial for our overall health, but did you know that it may also be linked to improved fertility in women who have polycystic ovarian syndrome (PCOS). PCOS is an inflammatory condition that is related to abnormal hormone levels in the body, particularly insulin which is needed to help regulate blood sugar levels. Women who have PCOS often experience irregular periods, excess androgen (male hormones in the body), and polycystic ovaries, all of which can negatively impact women’s chances of falling pregnant. You can read more about PCOS here.
Recent research has found that supplementation with probiotics, a form of ‘live’ bacteria that directly increases the amount of good bacteria present in the gut, or Synbiotics which is a mixture of helps to improve various inflammatory, hormonal, and metabolic markers which could help improve fertility in women with PCOS.
Male fertility
Of course, when it comes to fertility it’s not just women that can do things to help improve their chances of conceiving. For men, having a healthy and balanced diet, as well as regular exercise and refraining from smoking and excessive alcohol consumption may all help to improve the quality and quantity of sperm. There are also certain nutrients, such as selenium which is found in Brazil nuts, fish, meat, and eggs; zinc found in meat, shellfish, bread and other cereal products; and omega-3 fatty acids that may influence fertility and sperm production.
*Trigger warning: this next section discusses miscarriages*
Vitamin D & risk of miscarriage
Vitamin D, known as the sunshine vitamin, is created by our bodies when we are exposed to direct sunlight. It can also be found in small amounts in some foods such as oily fish, egg yolks, and fortified breakfast cereals. We need vitamin D to help regulate the amount of phosphorous and calcium within the body which is needed to help keep our teeth, bones, and muscles healthy. We also need vitamin D to help support a healthy immune system.
Whilst this vitamin is not directly related to fertility and falling pregnant, having a healthy and successful pregnancy is still of utmost importance. The latest research carried out by Tommy’s helps to understand why, sadly, some pregnancies end in a loss. Their studies have found that a vitamin D deficiency is linked to an increased risk of miscarriages (a pregnancy loss before 23 weeks) or recurrent miscarriages (3 or more miscarriages in a row) in pregnant women.
An adequate vitamin D intake in pregnant women is essential for both the health and wellbeing of both the mother and baby. Epidemiological evidence, i.e. data from studies that examine the prevalence and distribution of medical conditions and disease, has revealed that many pregnant women have suboptimal vitamin D levels within their body. This may have negative implications during pregnancy, as data has suggested that a vitamin D deficiency may be linked to preeclampsia, gestational diabetes, bacterial vaginosis, and an increased risk for having a C-section delivery.
Experts have also found that vitamin D is essential for bone development in a growing foetus, as well as having an important role in early pregnancy in mother and baby immune responses and blood vessel development, both of which are needed in a healthy pregnancy.
The most recent evidence, in a review lead by Tommy’s researchers, now also suggests that a vitamin D deficiency during pregnancy significantly increases the risk of miscarriage or recurrent miscarriage. Researchers found that vitamin D plays a role in maintaining a healthy placenta, the organ responsible for delivering oxygen and nutrients to foetus. In women with low vitamin D levels this negatively impacts the function of the placenta, which results in a miscarriage.
This evidence highlights the importance of pregnant women maintaining adequate vitamin D levels through dietary sources and supplementation using a high quality supplement such as Rhitrition+. This is particularly important if you are at risk or during the autumn and winter months in the UK. The researchers behind this review also suggested the need for more research to be carried out to understand whether treatment of a vitamin D deficiency in women in the preconception period is needed to also protect against the risk of miscarriage.
If you’re concerned about your fertility, it’s always best to seek advice from your GP or from a specialist healthcare professional. There are also plenty of resources out there that may be useful to help you to understand how to optimise your diet and lifestyle to promote and support healthy fertility and pregnancy outcomes. Here are just a few good places to start…
Useful resources from Rhitrition
Food For Thought Podcast episodes:
https://podcasts.apple.com/gb/podcast/food-for-thought/id1441209943?i=1000444994652
https://podcasts.apple.com/gb/podcast/food-for-thought/id1441209943?i=1000490309067
Books:
Rhiannon’s latest book Deliciously Healthy Pregnancy
Clinic:
At the Rhitrition clinic we have the wonderful Komal who is a registered dietitian specialising in fertility and pregnancy nutrition. Enquire here.
A big thank you to @dietitianro from @fertility.dietitian.uk for sharing this research through her newsletter! This blog was written by Ellie Morris, the Clinic Manager for Rhitrition and soon-to-be associate registered nutritionist. She has just finished her MSc in Applied Human Nutrition at Oxford Brookes, and has previously completed an internship with Clarissa Lenherr Nutrition, and was an applied sports nutrition intern at the University of Birmingham. Ellie has also had some experience as part of the MyNutriWeb team to learn the behind the scenes of one of the UK’s leading nutrition CPD resources. She shares yummy meal and snack ideas over on her Instagram @nutritiouslyellie.
References:
(1) https://www.nhs.uk/conditions/infertility/
(2) https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-b/
(3) https://pubmed.ncbi.nlm.nih.gov/34809974/
(4) https://pubmed.ncbi.nlm.nih.gov/35779332/