While it is always better to get the vitamins and minerals your body needs from the food you eat, and most adults should easily receive everything they need by eating a nutritious, healthy and balanced diet, you may occasionally be advised by your doctor to top-up your intake with supplements.
Even if you are trying to eat a healthy diet the food we eat has become depleted in nutrients over the years. For example, compared to the 1930s, the fruits and vegetables we eat contain an average of 20% fewer minerals (magnesium 24%, calcium 46%, iron 27% and zinc 59%). With regard to meat and dairy, iron in meat has been depleted by 47%, iron in milk by over 60%, calcium loss in cheese by 15% and Parmesan cheese by 70% (The Independent Food Commission’s Food Magazine 2005).
The soil that our food is grown in has become depleted in vital nutrients from over farming and the use of pesticides. And many fruits and vegetables on the supermarkets shelves have travelled hundreds of miles over a number of days with the nutrients becoming depleted the longer it’s been since they were picked.
Also, if you have been dieting in the past and cut out certain food groups (e.g. low or no fat diets) or restricted your calories it may be that you are deficient in vital nutrients, like omega-3 essential fatty acids.
Your diet is always the foundation of your health and the aim with fertility nutrition is to add-in certain key nutrients that we know are important for fertility for both men and women.
There is now a great deal of scientific knowledge about the use of nutritional supplements and their beneficial effects on both male and female fertility. These supplements can help to improve you and your partner’s overall health and certain nutrients have been shown to help increase the chances of IVF working.
An essential B vitamin, folic acid is absolutely crucial for a healthy pregnancy, but it is also one of the vitamins in which we are most commonly deficient. Your body needs folic acid to produce DNA. Folic acid protects the neural tube – which will go on to form the spine and spinal cord – and helps to close it properly to ensure normal brain and spinal cord function. Folic acid can help to protect an unborn baby from developing spina bifida. The neural tube should close between the 25th and 30th day after conception, when women may still not realise they are pregnant, which is why all women aiming to get pregnant should take folic acid each day for up to three months before conception.
High levels of an amino acid called homocysteine which should be detoxified by the body has been found in women who miscarry. Homocysteine is controlled not only by folic acid but also two of the other B vitamins, B6 and B12. So having a fertility supplement containing not only folic acid but also these other B vitamins is important.
Men should also consider taking folic acid supplements as new evidence suggests that folic acid deficiency reduces fertility in men and may damage the DNA carried by sperm. And we know that a combination of folic acid and zinc can increase sperm counts by up to 74%.
Zinc is the most widely studied fertility-boosting nutrient for both men and women. It is an essential component of genetic material and a deficiency can lead to reduced fertility, hormone imbalance and an increased risk of miscarriage. Zinc is found in high concentrations in the sperm. It is needed to make the outer layer and tail of the sperm and is, therefore, essential for its health.
Research suggests that zinc deficiency in men causes a temporary but reversible reduction in sperm count and a reduced testosterone level; giving zinc to men with low testosterone levels increases sperm count. Other studies comparing men with low sperm counts with those whose sperm counts are normal show that zinc levels are significantly lower in the men with low sperm counts.
Zinc is vitally important for growth and proper cell division in the embryo. During IVF treatment, after the egg has fertilised the doctors have to wait for the cells to divide healthily before transferring the embryo back.
This mineral is used to make antioxidants called selenoproteins which help protect your body from free radical damage – very important in the process of cell division. With its protective effect selenium can prevent chromosome breakage which is known to cause birth defects and miscarriages. Selenium deficiency in women has been linked to a higher risk of miscarriage.
Good levels of selenium are also essential for sperm formation and testosterone production in men. A lack of selenium in men is associated with poor sperm motility, selenium being essential for making their strong whiplash tails. In one double blind trial selenium supplementation resulted in an increase in fertility from 17.5% to 35.1% in sub-fertile men. Other studies show that blood selenium levels are lower in men with low sperm counts.
Research suggests that the antioxidant activity of selenium may even make sperm more fertile. An interesting study looked at men with good sperm counts but low fertilisation rates during IVF treatments. They were given selenium and vitamin E supplements each day and one month after starting treatment their fertility rate increased from 19% to 29%
Omega-3 fatty acids
Over the last century there has been an 80 per cent decrease in the consumption of omega-3 fatty acids. It is now thought that we are getting too many omega-6 fats from our diet and not enough omega-3s.
Omega-3 fats are important for regulating reproductive hormones and boosting your baby’s brain, eye and central nervous system development. Omega-3 fish oils have also been shown to help prevent blood from clotting inappropriately, so it can be beneficial to women in whom recurrent miscarriages have been linked to a clotting problem.
For men, omega-3 supplementation is important because semen is rich in the prostaglandins produced from these fats. Research has shown that men with higher levels of abnormal sperm tend to have lower than normal levels of omega-3 fatty acids.
Because our Western diet is usually high in omega 6s, found in abundance in many vegetables oils, you should decrease your intake of vegetable oils and boost your intake of less abundant omega-3s. We are aiming for a ratio of about twice as much omega-6 in our blood to omega-3 (2:1). But it is estimated that the ratio many people are getting nowadays is as high as 25:1. Women also tend to take evening primrose oil supplements which are omega-6, so that is making the situation worse.
The Department of Health recommends that we should all double our intake of omega-3s by eating oily fish (such as salmon) two to three times a week and more green, leafy vegetables and beans. But more and more research indicates that it is wise to use supplements for these fatty acids and not to rely on dietary intake. It is recommended that all couples trying for a baby start supplementing with essential fatty acids several months before conception.
Avoid cod liver oil capsules. Oil taken from the liver of the fish – the organ of detoxification – can contain high levels of heavy metals like mercury and also carcinogens like dioxins. Cod liver oil will also contain high levels of vitamin A, which is not recommended during pregnancy. Choose fish oil capsules that are from the body of the fish rather than the liver.
Vitamin B6 is important for the development and maintenance of a healthy immune system and consequently protects against cancer as well as infection. It can help to prevent damage to chromosomes which is obviously crucial at the point of conception. Many women use vitamin B6 for the relief of premenstrual syndrome and irregular periods with some success and it also plays a critical role in fertility. In addition, vitamin B6 is intricately involved in the function of many enzymes and in protein metabolism and formation.
Vitamin B12 is a water-soluble vitamin, like the other B vitamins, so your body is unable to store extensive amounts and must therefore get a regular supply from the diet. This can be difficult for some people, either because they absorb vitamin B12 poorly or because their diet is deficient, especially in the case of vegans.
Vitamin B12 is vital for cellular reproduction and a number of studies have shown its potential for reducing the risk of miscarriage.
Vitamin E is a powerful antioxidant and has been shown to increase fertility when given to both men and women. With men, vitamin E helps to increase fertilisation rate. If you are a woman and over 35 and you have been told that your fertility problems are caused by your age, then you are likely to benefit from taking both vitamins E and C. These antioxidants have been shown to significantly reduce age-related ovulation decline.
This key antioxidant is good for your general health but research has shown that giving vitamin C to women undergoing IVF treatment significantly increases the pregnancy rate.
Studies have also established that deficiencies in vitamin C can decrease sperm quality. In one study, when a group of men had their vitamin C intake reduced to 5mg a day their sperm had double the normal DNA damage. In another it was shown that supplementing with 1000mg of vitamin C increased sperm quality and quantity. Vitamin C reduces agglutination (when sperm stick together, affecting fertility) and can increase sperm counts by up to a third.
Antioxidants in general, which includes not just vitamin C but also vitamin E, zinc and selenium, can have a significant impact on male fertility. One large review in 2011 showed that men undergoing assisted conception like IVF or ICSI, the men taking antioxidants were five times as likely to have a successful treatment resulting in a live birth compared to those men taking a placebo.
This fat soluble vitamin is important for fertility for both men and women. For women it is known that having good levels of vitamin D helps the body maintain a pregnancy by effectively switching off the part of the immune system that could reject the baby because only half its DNA is the mother’s.
Vitamin D is also important for male fertility as low levels of this nutrient is associated with low sperm motility and more abnormal forms.
But the problem is that many people, and women especially, are deficient in vitamin D and won’t even know it. We have alarmingly low levels of vitamin D in the UK, more than 50% of adults has insufficient vitamin D levels.
You are most at risk in the UK if you do not go out much in the daytime, do not expose your skin to the sunlight and if you constantly wear make-up or cosmetics with in-built sun protection factors and may not realise they are in the beauty products. The tone of your skin affects vitamin D production. The darker your skin the less vitamin D production and covering up large areas of skin for religious reasons will also reduce vitamin D production. It is estimated that we need about 30 minutes exposure to the sun up to three times a week to produce enough vitamin D.
Natural food sources of vitamin D are few. It is found in oily fish and eggs. 100g of grilled salmon contains 284ius of vitamin D and 100g of tinned pilchards contains 560ius of vitamin D. The yolk of one egg contains about 20ius of vitamin D. Other sources would include fortified foods such as margarines and breakfast cereals, but it is better to choose butter and the fortified breakfast cereals are likely to contain added sugar.
Amino acids have been proven to be important supplements for men in addressing infertility problems. The head of the sperm contains a large amount of L-arginine – an amino acid found in many foods and one that is essential for sperm production. A great deal of research has shown that L-arginine deficiency should be considered when there are problems with sperm and male fertility. Studies suggest that increasing levels of L-arginine can increase sperm count and quality.
Another amino acid that appears to be crucial for healthy sperm function is L-carnitine and studies have shown that supplementing with it helped to increase sperm count.
This is a vitamin-like substance that is contained in nearly every cell of the body. It is important for energy production and normal carbohydrate metabolism (the way the body breaks down the carbohydrates you eat in order to turn it into energy).
Because of its role in energy production it is a significant nutrient for men if sperm motility is poor. Co-enzyme Q10 is concentrated in area between the head and tail of the sperm; the energy for movement and all other energy-dependent processes in the sperm cell depend on it. Lower levels of co-enzyme Q10 have been found in men with poor sperm motility and supplementing with this nutrient led to a significant improvement.
As co-enzyme Q10 also functions as an antioxidant it can help sperm cells in protecting membranes from free radical damage and so would be suggested for those who have a higher proportion of abnormal sperm or high DNA sperm damage.