Written by Ben Bunting: BA(Hons), PGCert.
Whilst trying for a baby, you and your partner may be more conscious of what foods and drink you consume.
There’s plenty of evidence available that places good nutrition at the heart of fertility, and likewise, poor nutrition along with certain lifestyle factors that can reduce sperm health or sperm count and overall hormonal status that can hinder your chances of conceiving.
In this article we look at walnuts, what their nutritional status is and why they may be a good staple to add to your diet.
What are Walnuts?
Walnuts are a type of tree nut that is grown on the walnut tree, actually they are an edible seed, but are referred to as a nut. Walnuts are grown in the United States, China, and Turkey.
They are harvested in late summer and early fall and can be eaten raw or roasted. Walnuts have been used for centuries as a food source, but they also have many other uses. For example, they can be used to make soaps, cosmetics, and dyes.
What’s the Nutritional Value of Walnuts?
Walnuts are packed with a host of nutritional benefits, and just a small portion is overflowing with energy, vitamins, minerals, and electrolytes.
So, let’s go through what the mighty walnut consists of:
Each walnut is rich in carbohydrates, protein, and fats this makes it the ideal food source for anyone leading an active lifestyle.
Carbohydrates are the primary and preferred fuel source for brain function and activity.
Protein helps muscle recovery, development, and synthesize hormones.
However, more importantly, walnuts contain a majority of monounsaturated and polyunsaturated fats. These two fats are gained from plant sources and seafoods.
They help reduce the bad cholesterol that can line your arteries and prevent the risk of heart disease and stroke. These tend to be liquid at room temperature.
Furthermore, the polyunsaturated fat content also includes essential fatty acids that your body can only get from food sources. These are Omega-3 and Omega-6 fatty acids.
These fatty acids are beneficial to heart health. They help reduce the build up of artery plaque which reduces the diameter of your arteries and blood vessels meaning it is harder for the heart to pump blood.
In some cases, this plaque build-up can clog the arteries and harden them which leads to heart disease and stroke.
Omega-3 acids can also reduce blood pressure and lower the risk of an irregular heartbeat.
Again, Omega-6 fatty acids are great for helping reduce your blood pressure, but they can also control your blood sugar and reduce the risk of diabetes.
In this section we will only comment on the benefits of those micronutrients that contribute to the daily recommended values (DRV) or recommended daily allowance (RDA) per a 100g portion.
Thiamine is a water-soluble vitamin that is essential for the metabolism of carbohydrates and fats. It also helps in the production of energy from food.
The benefits of thiamine are:
-It helps in the production of energy from food
-Improves the metabolism of carbohydrates and fats
-It is essential for growth and development
-Helping to maintain healthy skin, hair, eyes, heart, muscles, and nerves
Riboflavin is a water-soluble vitamin that is found in many foods. It is also available as a dietary supplement. Riboflavin helps the body convert food into energy and supports healthy skin, eyes, and hair.
The benefits of riboflavin include:
- Supports healthy skin, eyes, and hair
- Helps the body convert food into energy
- Supports the immune system
- Promotes normal growth and development
Niacin is a water-soluble B vitamin that is essential to produce energy from food. It also helps to maintain healthy skin and nervous system.
This B vitamin is found in many foods, including meat, fish, poultry, eggs, milk, and dairy products. It can also be taken as a dietary supplement.
The benefits of niacin include:
-Helps to maintain healthy skin and nervous system
-Helps to produce energy from food
-Can be taken as a dietary supplement
Pantothenic Acid (B5)
Pantothenic acid is a water-soluble vitamin that is essential to produce energy and the metabolism of fats, proteins, and carbohydrates. It also helps to maintain healthy skin, hair, and nails.
Vitamin B5 is found in many foods such as whole grains, legumes, vegetables, fruits, eggs, milk products and meats.
Vitamin B6 is a water-soluble vitamin that is essential for the metabolism of protein and amino acids. It also helps in the production of red blood cells, and it aids in the production of serotonin, a neurotransmitter that helps regulate mood.
The benefits of Vitamin B6 are:
- Helps in the production of red blood cells
- Aids in the production of serotonin
- Helps with protein and amino acid metabolism
- Contributes to mood regulation
Folate is a water-soluble B vitamin that is essential to produce DNA and RNA. It also helps in the production of red blood cells and in the metabolism of amino acids.
The benefits of folate include:
-Helps to prevent neural tube defects, such as spina bifida, in developing fetuses
-Helps to reduce levels of homocysteine, an amino acid that can damage blood vessels and lead to heart disease or stroke
-Contributes towards lowering levels of a type of cholesterol called low-density lipoprotein (LDL)
-May help protect against colorectal cancer
Vitamin C is an essential nutrient that the body cannot produce on its own. It is a water-soluble vitamin that helps the body form collagen, which is a protein that provides structure to skin, bones, and other tissues.
Vitamin C also helps maintain healthy teeth and gums, aids in iron absorption, and supports immune system function.
The benefits of Vitamin C are:
-Helps form collagen which provides structure to skin, bones, and other tissues
-Aids in iron absorption
-Supports immune system function
-Helps maintain healthy teeth and gums
Vitamin E is a fat-soluble vitamin that is found in many foods. It is an antioxidant that helps protect cells from damage caused by free radicals.
Vitamin E has been shown to help reduce the risk of heart disease, cancer, and cataracts. It also helps maintain healthy skin and hair.
Vitamin K is a fat-soluble vitamin that is essential for blood clotting. It also helps in the production of proteins that are important for bone health.
The benefits of Vitamin K are:
-It helps in the production of proteins that are important for bone health
-Vitamin K is essential for blood clotting and prevents excessive bleeding
-It helps to maintain healthy bones, teeth, and skin
Minerals and Electrolytes
Calcium is an essential mineral that is needed for the development and maintenance of healthy bones and teeth. It also helps to regulate muscle contractions, blood clotting, and nerve signalling.
The benefits of calcium include:
-Contributes towards maintaining strong bones
-Aids the regulation of muscle contractions
-Helps to maintain normal blood clotting
-Supports nerve signal transmission
Iron is a mineral that is essential to produce hemoglobin and myoglobin. It is also important for the transport of oxygen in the blood.
Iron deficiency can lead to anemia, which can cause fatigue, shortness of breath, and pale skin. Iron deficiency can also lead to impaired cognitive function and increased risk of infection.
The benefits of iron include:
-Helps with cognitive function
-Improves athletic performance
-Increases energy levels
Magnesium is a mineral that is essential for the body to function properly.
It helps maintain normal muscle and nerve function, keeps heart rhythm steady, supports a healthy immune system, and keeps bones strong.
Magnesium also helps regulate blood sugar levels, promotes normal blood pressure, and is known to be involved in energy metabolism.
The benefits of magnesium are:
-Contributes to maintaining normal muscle and nerve function
-It supports a healthy immune system
-Improves bone strength
-Works to regulate blood sugar levels
-Promotes normal blood pressure
-It is involved in energy metabolism
Manganese is a chemical element that is used in steel production. It is also used in the production of batteries, fertilizers, and other chemicals.
Manganese has many benefits for humans and the environment with manganese being found in soil, water, plants, animals, and humans.
-Helps promote bone strength and health.
-It helps to make blood cells healthy and fight infection
-Manganese can help to prevent cancer cells from growing too quickly or spreading throughout the body
Phosphorus is a chemical element that is essential for all living organisms. It is the 11th most abundant element in the Earth's crust, and it is found in many foods.
The element has many benefits to humans, animals, and plants. It helps with bone development, nerve function, and energy production.
Potassium is a mineral that is essential for the human body. It helps to regulate blood pressure and heart rate, and it also helps to maintain healthy bones.
This electrolyte is found in many foods, including bananas, potatoes, spinach, and avocados.
Zinc is an essential mineral that is required for many bodily functions. It is a component of more than 100 enzymes and plays a role in the immune system, DNA synthesis, and cell division.
A deficiency of zinc can lead to stunted growth, delayed sexual maturation, impaired wound healing, and poor appetite.
Zinc deficiency can also lead to hair loss, skin lesions, diarrhea or constipation, eye problems such as night blindness or dry eyes.
The benefits of zinc are:
-Promotes wound healing
-It helps with the immune system
-Contributes to DNA synthesis
-It helps with cell division
So, even before we investigate any potential benefits for male fertility, we can see walnuts are worth adding to our diet.
Are Walnuts good for Sperm?
Let’s take a quick overview of sperm.
Sperm is the male reproductive cell. It is produced in the testes and stored in the epididymis.
The spermatozoa are motile and have a head, neck, a midpiece and a tail. The head contains the nucleus with genetic material, while the tail propels it.
Spermatozoa are produced through meiosis of spermatogonia cells which divide to form primary spermatocytes. These cells then divide again to form secondary spermatocytes which then divide into spermatids.
The final stage of maturation is when these cells become fully mature spermatozoa with the ability to fertilize an egg cell or ovum.
The process of fertilization involves one spermatozoon penetrating an ovum membrane.
What is in sperm?
Sperm consists of numerous secretions which includes the following nutrients as outlined by an article published in the Journal of Clinical Medicine reviewing the nutritional factors associated with male fertility:
- acid phosphatase
- citric acid
- vitamins C and E
- neutral alpha-glucosidase
- electrolytes - sodium and potassium
It is recognised that many of these components required for healthy sperm is from food sources.
However, what is more telling is that those who are infertile have a reduced amount of zinc, magnesium, calcium, copper, and selenium in their sperm. With walnuts containing rich amounts of zinc, magnesium, and calcium.
Furthermore, nuts and seeds are identified as being a key dietary component for improving sperm quality with particular focus on walnuts for those men who consume a typical western diet where they improved sperm vitality, motility and morphology.
Impact on Male Fertility
Infertility affects up to 12% of couples around the globe, and it is a growing concern, something that may be attributed to poorer dietary and lifestyle choices.
Furthermore, male related sub-fertility factors contribute to around half of the problem, with sperm health being associated with shorter time to pregnancy rates.
A random clinical trial conducted and published by Robins et al (2019) demonstrated that including walnuts to the diet of men who were seeking care for infertility resulted in higher pregnancy rates and was beneficial to sperm motility and morphology.
These outcomes are further compounded by this study published in 2020 which confirmed that adding walnuts to the diet of infertile men can improve sperm health over a 3 month period.
Are Walnuts Good for Male Fertility? Concluding Remarks
Walnuts are a good source of omega-3 fatty acids, which are important for male fertility. Omega-3s can help to improve sperm quality and motility. Walnuts also contain antioxidants that can help to reduce oxidative stress in the body, which is associated with infertility.
This rich source of nutrients has proven to improve sperm parameters amongst fertile and infertile men, leading to increased pregnancies and improved time to pregnancy rates.
Therefore, if you are looking to have a baby, adding walnuts to your diet could help you conceive quicker.