Cod Fish and Thyroid Health

Wild caught Cod* is high in protein and a variety of vitamins and minerals – making it a great addition to a fertility diet. 

Chinese Fertility Medicine recognises specific Qi (chee) strengthening qualities for cod as described in more detail below.

A 100g portion of cod can provide as much as 47% of your daily value of Selenium! 

This is great news for anyone with thyroid issues (particularly Hashimotos Thyroiditis) as selenium supports thyroid health. It also helps reduce high Mercury levels.

Cod is also another rich source of Omega-3 fats like many other types of fish.

100g of cod also contains around:

  • 22g of protein
  • 15% RDA of Vitamin B12
  • 12% RDA of Vitamin B6
  • 10% RDA of vitamin B3 
  • 20% of your daily value of Phosphorus

I recommend eating around 2 portions of fish in your diet per week to make a total of around 350-450g per week. This will typically provide you with sufficient Omega-3 for the week, meaning you don’t need to supplement – particularly if you are also gaining Omega-3 from other food sources such as meat and animal fats.

As with all fish Cod should ideally be bought fresh and not in frozen form. This allows you to assess the health and quality of the fish, and possibly have access to higher levels of nutrients.

Key nutrients are:

Vitamin B12 – Also known as Cobalamin is an essential nutrient that is involved in the creation and maintenance of red blood cells, nerve cells, and the coating of nerve cells.

Aiding in the production of DNA, RNA, and neurotransmitters, it is a really important nutrient for developing healthy eggs and sperm – and also for your babies’ future health development. 

Vitamin B12 is not found in sufficient amounts in the plant world and so vegetarians and vegans will struggle to get this nutrient. Supplementation may help, but there will also be a lack of the supporting elements of natural B12. 

Deficiency of vitamin B12 leads to anemia, fatigue, depression and in severe cases it may lead to Multiple Sclerosis or seizures. 

Vitamin B3 – Vitamin B3, also known as Niacin, as with most other B vitamins is also involved in energy production within the mitochondria of your cells (the powerhouse of the cell). 

It is an important part of the entire Vitamin B complex, which should be adequate in your diet to support your general and fertility health. Pregnancy requires good levels of niacin, as does breastfeeding. 

As Niacin can not be stored in the body it is important to include it in your diet every day. You should be able to get the required amount of B3 by eating a varied and balanced diet.

Vitamin B6 – Also known as Pyridoxine is involved in breaking many types of chemical bonds. It is a component of many enzymes, which are involved in breaking down foods and substances, and also regulating steroid hormones.

B6 also helps in the production of neurotransmitters, which are the chemicals that allow brain and nerve cells to communicate – and this ensures that metabolic processes such as fat and protein metabolism happen properly. 

B6 is also a strong component of the immune system, which makes it vital to have in your diet whilst trying to conceive.

It can also help address a number of conditions, including: nerve compression injuries (like carpal tunnel syndrome), premenstrual syndrome (PMS), and some cases of depression and arthritis. Vitamin B6 is often used to treat high homocysteine levels along with folate and Vitamin B12. 

Vitamin D – Vitamin D is a fat-soluble hormone produced through exposure of the skin to sunlight, and is a vital nutrient for many processes in your body.

Research has shown that there may be a strong correlation between Vitamin D levels and AMH (Anti-Mullerian Hormone).

Vitamin D helps with the absorption of calcium and promotes bone mineralisation, which may prevent or slow the progression of osteoporosis. It also helps to strengthen the immune system and protect against a number of serious diseases, including rickets and osteomalacia.

Before taking vitamin D as a supplement it is important to test your levels and see if they are low. Don’t assume that Vitamin D is low without testing it. 

If your Vitamin D levels are in the normal range then do not supplement.

If your levels are below the normal range you could consider supplementing until your levels rise. Once supplementing you must re-test your Vitamin D every few months, as synthetic supplementation builds up in the Liver. During the months of March – October you will most likely find you get enough vitamin D through sun exposure and a varied balanced diet.

Calcium – Calcium is needed to build and maintain strong bones, support heart health, and for optimal function of the muscles and nerves. It is also required alongside Vitamin D to aid in its use throughout the body.

Iron –  Iron is a mineral that the body uses to carry oxygen in the blood. 

It has many functions but also plays a key role in strengthening the immune system and regulating body temperature.

Magnesium – Magnesium supports a healthy immune system as well as keeping bones strong. It is also great for stress, and combined with vitamin B6 can help induce sleep and alleviate symptoms of bloating and weight gain associated with PMS.

The production of Vitamin D also relies on Magnesium, and many people that are deficient in Vitamin D also have a Magnesium deficiency. Before taking a Vitamin D supplement I would recommend increasing Magnesium intake, whilst also increasing sun exposure, and then retest Vitamin D levels after 4 weeks. 

Many people experience heightened stress levels and develop magnesium deficiency as it is a difficult nutrient to obtain from your diet. Crab meat has a high source of Magnesium, but many people will need to supplement this mineral.

Magnesium is helpful for cell function, and if you become deficient you can quickly experience increased stress feelings, disturbed sleep, or muscle cramping.

Zinc – Zinc benefits include maintaining brain function, strengthening bones, boosting your immune system, increasing energy levels, and enhancing reproductive health.

Zinc is essential for the repair and function of DNA, which affects sperm and egg quality. 

It’s also essential for the rapid growth of cells and the building of major parts of cells during a pregnancy. The development and enzyme activity that takes place during pregnancy is supported by zinc, which means that this is one of the most important nutrients for babies and mothers.

Zinc is also involved in making red blood cells (along with iron) and haemoglobin, which transports nutrients around your body helping to support your organ and cellular health.

In women zinc supports all of the reproductive phases, including the stages of birth and milk production.

In men zinc assists in spermatogenesis and the development of the sex organs.

For sperm health this mineral plays a major role in a number of ways:

  1. It acts as a sedative for the sperm so that they don’t expend energy unnecessarily.
  2. It protects the reproductive DNA inside the sperm from breaking down, so a correct transfer of genetic information takes place.
  3. Once inside the female reproductive tract the sperm quickly disperses and has a sudden burst of activity, which propels it towards the fallopian tubes.
  4. Zinc is an essential part of the enzymes that allow sperm to penetrate into the female egg

PotassiumPotassium is an electrolyte which counteracts the effects of sodium, helping to maintain consistent blood pressure levels – another important element for pregnancy. Many processes in the body rely on a small electric current to function, and electrolytes provide this current.

Potassium is required to keep the brain, heart, kidneys, muscle tissue, and other important organs in good condition. Its health benefits are; boosting the immune system, Improving bone health, improving muscle strength, blood sugar regulation, blood pressure regulation, and maintaining optimal nerve and brain function.

Phosphorus – Phosphorus is an element that plays an important role in how the body uses carbohydrates and fats. It is also needed for the body to make protein for the growth, maintenance, and repair of cells and tissues. It is essential in our diet and particularly in children when growth and development occurs most.

The health benefits of Phosphorus are: improved digestion; formation of healthy bone; hormone balance;  kidney health; elimination of muscle weakness and fatigue; muscle maintenance; and repair of cells and tissues.

Selenium – Selenium is one component of antioxidant enzymes and is also used by the body to help support thyroid health – particularly the conversion of thyroid hormones from one to the other. Thyroid health is fundamental to your general and fertility health and future pregnancy.

Sodium – Sodium has many health benefits including promoting digestion, promoting restful sleep and preventing muscle cramps.

It plays a role in the conduction of nerve signals to the brain, which is essential for movement. Sodium also helps with the regulation of blood pressure and volume, and fluid maintenance, to ensure you have enough fluid around your cells. This is important for the health of all cells including egg and sperm cells.


  • Treat Blood Stagnation
  • Treat Qi Deficiency
  • Treat Dampness


Blood Stagnation refers to poor circulation of blood throughout the body.

This can manifest in any aspect of the body but is prevalent in many male fertility, and gynecological issues.

There are 2 main causes of Blood Stagnation:

  1. A genetic clotting disorder that directly causes the blood to clot more easily
  2. A Blood Deficiency pattern where the blood is weaker and cannot flow efficiently, causing it to become stagnant

Healthy Blood flow is vital to nourishing all the cells in your body, which include egg and sperm cells.

If blood flow reduces it may cause male and female fertility issues that typically present with either an obstruction in the flow of blood or fluids, or the development of a growth or mass.

Click here to read more about Blood Stagnation


Qi is the word used in Chinese Fertility Medicine to describe energy, life force, or vitality inside and outside the body.

Qi is the non-physical aspect of your body that makes all of your organs and systems work.

This means that it’s vital for the function of all aspects of your fertility, and pregnancy health too. When your Qi is deficient your body struggles to function efficiently, and this can lead to a variety of fertility issues.

When Qi becomes more severely deficient you will likely present with hormone imbalance, typically with reduced Progesterone, Testosterone and/or FSH levels. In some cases the FSH can rise and present itself as being elevated, due to the ovaries or testes being underactive and sluggish (tired).

Click here to read more about Qi Deficiency


Dampness is the word used in Chinese Fertility Medicine to describe an overabundance of negative types of fluids that have accumulated in the body.

This includes: mucus, phlegm, or water accumulation (edema) that build up over time in different areas of the body.

A variety of fertility issues can arise from having too much Dampness including: immune disorders, fluid retention, circulatory issues, bacterial and fungal overgrowth, and other inflammatory diseases.

Reducing dampness can take some time, but the physical effects you receive will be worth it!

Click here to read more about Dampness

Season Available: Spring although available all year round

How it’s typically cooked: Cod fish can be poached, steamed, baked or pan fried, although frying will significantly reduce its nutrient content. One of the most nourishing ways to eat fish is in the form of fish stock, which is made from the heads and bones of the fish.

* As with all fish, Cod should only be consumed when sourced from the wild and ideally line caught. I do not promote eating farmed fish that is not 100% wild.

Cautions:You may need to avoid all fish if you have skin issues such as eczema, acne or psoriasis.







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