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Omega 3- the missing piece of your fertility puzzle?

Omega 3 fatty acids is a popular topic amongst my clients and one that has been talked about for years now with more and more supplements emerging that promise to improve our brain health, heart health, and now our fertility. There are a huge amount of omega 3 supplements available out there but do we need omega 3 supplements and are they worth it? 

What is omega 3? 

Omega 3 is one of the two types of polyunsaturated fatty acids, the other being omega-6. Within the category of omega-3 fats there are then two main types of fatty acids:

  1. ALA (alpha linoleic acid) 

  2. Long chain n-3 fatty acids (including EPA and DHA)

You might have noticed that there is often an emphasis on the importance of eating more oily fish specifically compared to that on adding in more nuts and seeds. The reason for this is that oily fish is one of the richest sources of EPA and DHA- two kinds of omega 3 fatty acids proven to provide the most significant health benefits. Plant foods like nuts and seeds on the other hand are richer in ALA, with only small amounts of EPA and DHA. When it comes to fertility, it's the EPA and DHA that we really want as this has been proven time and time again to improve fertility.

However, this doesn’t mean that we should neglect ALA from plant-based omega 3 sources as it helps to compete with omega 6 in the metabolic pathway and the more omega 3 we metabolise versus omega 6, the better health outcomes we get! 

In saying this, omega 6 is so easy to get in the diet that it often out-competes omega-3 fatty acids resulting in a high omega 6: omega 3 ratio which is a big predictor of inflammation in the body. Therefore, your best bet on optimising omega 3s for reducing inflammation is to reduce omega 6 intake at the same time.  

Where are omega 3 rich foods found/ what are they? 

ALA is mainly found in plant foods including… 

  • Flaxseeds

  • Chia seeds

  • Walnuts

  • Legumes

  • Pumpkin seeds

  • Flaxseed oil

  • Soybeans

  • Tofu & other soy products

EPA and DHA on the other hand are primarily found in marine sources: 

  • Salmon

  • Trout

  • Sardines

  • Mackerel

  • Herring

  • Cod Liver Oil

  • Anchovies

  • Caviar

  • Oysters

The best thing you can do to boost your omega 3 is to eat fish with 2-3 meals every week. Make sure to avoid key sources of mercury e.g. (flake (shark), orange roughy, catfish, marlin and broadbill/swordfish- more on this on the NZ MPI website. If you are pregnant fish should still be enjoyed regularly- just make sure that it’s cooked properly! 

What is the role of omega 3s in fertility?

The benefits of including omega 3 and fish in the diet for fertility has been shown time and time again. One study found that  couples who ate fish twice a week had a higher likelihood of falling pregnant than those who ate fish less frequently (Gaskins, et al., 2018).

Another study found that diets rich in omega-3 fatty acids over a lifetime can prolong female’s reproductive function into advanced maternal age, compared to a diet rich in omega-6 fatty acids. Furthermore, diets rich in omega-3s also improves egg quality while omega-6 fatty acid intake has been associated with poor egg quality (Nehra, et al., 2012).

Omega 3 fatty acids likely play a role in successful implantation too with a recent study of one hundred women undergoing ART finding that women who had a higher intake of omega 3 in their diet, had higher rates of implantation than those who consumed less omega-3 (Chiu et al 2018). There is also evidence to show that omega 3s could support the production of progesterone in the luteal phase of a womans cycle, contributing to a greater likelihood of implantation success. 

What about once you’re pregnant?

Omega-3 fatty acids continue to be important right throughout pregnancy with studies highlighting a significantly increased risk (10x the risk infact!) of preterm birth before 34 weeks in women with low omega-3 intake (Olsen et al., 2018). This supports the meta-analysis conducted in 2016 which showed that omega-3 fatty acids are effective in preventing early and preterm delivery.

Of course, preterm birth can be dangerous for babies and it’s important to carry them as long as you can towards full-term to ensure that vital organs are given time to mature and develop.

So not only is omega-3 important for improving your chances of conceiving, it’s also important during pregnancy as well, and leaving it until you’re pregnant to think about increasing your intake may be too late. Optimising EPA and DHA status preconception should be prioritised, much like that of folate and vitamin D. 

Along with baby’s development and delivery date, omega-3 (specifically DHA) is critical in the development of baby’s brain and nervous system including their eye development (Coletta, et al., 2010).

One word of caution is that omega 3 supplements beyond 35 weeks of pregnancy is not recommended as this can increase the risk of excessive bleeding so you're best to stop them and re-commence post-birth.

How much do I need? 

Suggested Dietary Targets of omega-3 for the prevention of chronic disease:

  • 410 mg/day for non-pregnant women

  • 630 mg/day for men

American Pregnancy Association

  • 300 mg DHA daily for pregnant & breastfeeding women

  • 500 mg EPA & DHA for all adults

These are MINIMUM recommendations however with many studies showing the most positive outcomes associated with much higher intakes of omega-3. I recommend aiming for atleast 300mg DHA and 1000mg EPA and DHA combined during the preconception phase and throughout pregnancy.

Should I add in a fish oil supplement? 

If you are already taking a fish oil/ omega 3 supplement then make sure to check that the company is transparent about the quality of their fish in regards to mercury content. Most of the manufacturing process will remove mercury in a fish oil supplement though. 

If you can, dietary sources are the best way to get your omega-3’s. Aim to eat oily fish 3 times every week and include a mixture of plant based omega 3’s across your day. 

If you know that you can’t consistently eat this much omega 3 through your diet then a supplement can be considered alongside the advice of a dietitian. Make sure your supplement contains adequate amounts of EPA and DHA (plus omega 3!) to give you the best possible benefit (atleast 300mg DHA at a minimum). 

If you are looking for more science-backed advice on how to boost your diet for optimal fertility then make sure to tune into my FREE fertility nutrition masterclass. I cover the top 5 mistakes that I see way too often when it comes to trying to conceive.

Register now for access!


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