You are what you eat. So are your sperm. It turns out that sperm are incredibly sensitive to what we eat. When we eat foods that are good for fertility turns out that sperm counts increase, motility and morphology are better and even the DNA inside the sperm is healthier. Healthy sperm DNA decreases the risk of miscarriage and birth defects while improving odds of creating a healthy baby that will carry to term, So what makes healthy sperm? Let’s find out…
What are Sperm Made out of?
Like all cells, sperm are made out of fat, protein, sugar and DNA. But there are a few things that make sperm special. First, sperm are rapidly dividing cells. The testicle is made up of germ cells that are constantly dividing into cells that eventually mature into sperm. The constant division means that there is more DNA replication going on in the testicle than anywhere else in the body. This means that sperm need higher levels of nutrients that enable DNA replication. These happen to be the same nutrients that are important for pregnant women. (Embyros are also very fast dividing and therefore need support with DNA replication) Zinc and folate are the most publicized nutrients that have been shown to improve DNA replication. They are critical for healthy babies as well as healthy sperm.
Another difference between sperm and other cells is that they are swimmers. This might be a bit obvious but it can lead to a few unintended consequences. Something to know about sperm is that they aren’t just swimmers, they are one of nature’s most powerful single cells. Consequently they are packed with a cell equivalent of a V-8 engine. Like all powerful machines, sperm produce their share of exhaust. Just as your car takes gas in and sends combustion products out the tail pipe. Sperm take in sugar which it converts to energy and produces a bi-product that can often will contain reactive molecules can can cause damage to surrounding cells. Reactive Oxygen Species (ROS) are reactive molecules generated by cellular metabolic processes that float around and try to react with molecules around them. If you’ve ever poured peroxide on a wound and watched it bubble up, that is exactly what is going on inside the testicle with all the ROS generated by sperm.
Here’s the problem. sperm are vulnerable to damage by ROS. Small amount of ROS are used to help sperm capacitate (get them all excited to penetrate egg) but large amounts cause a ton of damage. It can damage the outer membrane rendering the sperm unable to fertilize the egg. Second, ROS can damage sperm DNA which can prevent the sperm from correctly fertilizing an egg, cause DNA replication problems for the embryo leading to miscarriages or birth defects.
Finally, sperm must penetrate the egg. To do this, they are equipped with a special cap called the acrosome. The acrosome contains enyzmes which break down the zona pellucida or outer layer of the egg allowing the sperm to fertilize it. It is essential to get enough omega-3s, particularly DHA, to ensure the proper formation of the acrosome. The acrosome is particularly susceptible to damage by ROS.
Dietary Impact on Testosterone Production
Testosterone is produced in the testicle and is a key ingredient to helping mature baby sperm into strapping lads that can go out and get the job done. Scientists don’t fully understand how testosterone helps sperm but they do know that as T levels lower, we see decreased sperm production and function and if T drops too low, sperm production ceases completely.
So what exactly is T and how is it produced? To get a back story on the body’s signaling pathways for producing testosterone see our articles on male reproductive hormones and hypogonadism. Testosterone is a steroid hormone. There are other steroid hormones which are naturally produced by the body. Some of the most recognized are estrogen, cortisol, and progesterone. All the steroid hormones have two things in common. First, they all bind to similar receptor in the cell which means they can interfere with each other. Having high coritisol (stress) levels or estrogen can interfere with testosterone’s uptake by the body. Second, they are all made out of cholesterol. In fact there is a specific order which the body converts cholesterol into a one hormone which converts to another and another and eventually converts into testosterone. What’s interesting is all estrogen in both men and women is made out of testosterone.
Enter aromatase. Aromatase is the enzyme that converts testosterone into estrogen. It resides in many different types of cells but it seems to be most active when in fat cells. Overweight men often experience elevated estrogen levels which are sometimes accompanied by low testosterone levels. Interestingly, there are also things in the diet that can increase or decrease aromatase activity. Eating sweets or processed grains spike insulin production which in turns increases aromatase. Alcohol consumption also increases aromatase activity and decreases testosterone levels. Zinc and various flavinoids have been shown to decrease it.
Optimizing Your Diet for Sperm Health
By eating enough of the right kinds of foods and limiting negative foods, you can boost your chances of conception and the health of your future baby.
Fats & Proteins
Getting enough of the right types of fats, cholesterol and protein are important for men who are trying to conceive and generally for men’s health. As mentioned above, Testosterone is made out of cholesterol so it is important to have minimal amounts of cholesterol in your diet. Remember, too much is bad on the heart so don’t overdo it. Balance cholesterol intake with healthy fats that are essential for fertility and keep your heart healthy. Polyunsaturated fats are the healthiest of all. A subset of these is the Omega-3s which contain DHA fatty acids. Getting enough DHA is critical for both men and women while trying to conceive. For the man, it plays a critical role in sperm production and testicle health. For women, it may improve conditions for implantation and promote healthy growth of the embryo.
Simple ways to add more Omega-3s into your diet:
Look for “balanced” or “natural” branded margarine, cooking oils and peanut butters. If you read the ingredients some of these are made with various types of omega-3s. The best ones contain fish oil or algea oils which are rich in DHA.
Try to eat fish once a week.
If you have an aversion to fish, fish oil pills and gummies are a nice alternative
Sugars & Carbs
Carbohydrates are made up of various types sugars which in turn provide energy to cells. As we digest food that contains carbs, the sugars are released into our blood stream. The pancreas releases a hormone called insulin which enables cells in the body to utilize the sugar in the blood. When we eat foods that are high in carbohydrates, our bodies respond with a spike in insulin production. If all the cells in the body have all the energy they need, extra sugar in the blood stream is stored in the liver. Over the course of the day, sugars are then brought back into the bloodstream from the liver to provide energy to cells. Once the sugar supply of the liver is depleted, we start feeling hungry, lathargic or cranky and the body turns to a back up system to provide energy to cells. Fat stored in fat cells is released into the bloodstream, converted into sugar by the liver and then released for cells to use. The process of converting fat into sugar is far less efficient and can only provide low levels of energy which is why athletes need to fill up on carbs prior to a big event.
Insulin also increases aromatase activity. As insulin levels increase, so does the conversion of testosterone into estrogen. A reduction in testosterone and an increase in estrogen is more likely to cause man boobs (gynecomastia), reduce muscle mass and facial hair growth before it causes any issues with sperm development. (Sperm get first dibs on testosterone made by the testicle) But, it can cause a negative spiral of leaving you tired and gloomy, which can increase snacking, which further imbalances hormone levels. This spiral can lead to trouble with your swim team if you let it get out of control.
A trick to dealing with carbs is to eat whole grains or high fiber sources of carbohydrates. Fiber collectively refers to molecules in food that cannot be digested. As foods that are high in fiber are digested, sugar is slowly released from them into the blood stream. Because the sugar is leeching into the blood slowly, the insulin response is much lower. In turn, aromatase activity stays low and less testosterone is converted into estrogen.
Key Nutrients & Antioxidants Required for Proper Sperm Development
Getting enough of key vitamins and minerals is essential for two reasons. First, several nutrients are key parts of the cell division process. If there is a deficiency, sperm won’t divide or mature properly. A diet high in nutrients can improve sperm count, motility and morphology as well as reduce DNA fragmentation. Second, as mentioned above sperm produce a large amount of reactive oxygen species which can damage them. Antioxidants helps to protect sperm and can increase count, motility and DNA integrity. So which nutrients do you need and where do you find them?
The following vitamins and nutrients have been shown in studies to have a positive impact on semen parameters – count, motility, morphology and DNA integrity. We take an in-depth look at each one to understand what it is, how it works and its role in male fertility. We’ll also list out the foods rich in each of the nutrients. It is important to note that most of the literature supports the idea that vitamins and nutrients only really work to improve fertility when they are balanced. If a man has a diet rich in vitamin C but deficient in folate for example, he is still likely to have impaired semen parameters.
One important note, it is possible to get too much of a good thing. Overdosing on vitamins and nutrients will not add additional benefits for your health or your fertility. Vitamin E, Selenium and Zinc particularly can be toxic in high quantities. It is difficult to overdose on nutrients when they are coming directly from your diet but it is possible when eating fortified foods or taking dietary supplements. So don’t over do it.
Coenzyme Q10 is a fatty molecule that can easily pass through the cell membrane and serves as a gear in the machinery that converts sugar and oxygen into cellular energy. While floating outside of cells, it serves as an antioxidant by binding to and neutralizing reactive oxygen species. Because they are swimmers, sperm need a lot of energy. They also produce a lot of ROS and therefore need antioxidants to protect them.
Also known as vitamin B9 and folic acid, folate is an essential vitamin that enables the body to replicate and repair DNA. Food rich in folate, such as spinach, kale, black beans and broccoli, are broken down by the liver to generate essential molecules that form the base of our DNA. These molecules are not produced by the body so it is important that we get them in our diet. From the liver, these molecules travel by blood to the body where cells are dividing and is used during DNA replication. Because germ cells are constantly dividing to create sperm, they are in constant need of folate to create top notch DNA.
L-Arginine is an essential amino acid generated by the body to support cell division, wound healing, immune function, removal of ammonia and supporting the release of several hormones. Arginine is used by the body in two ways. First, some of it is converted into nitric oxide which is a chemical that relaxes blood vessel walls allowing blood to flow into tissues. Second, it triggers the body to produce proteins that are essential for cell production and repair.
L-Arginine supports reproduction in a few ways. First, nitric oxide created from arginine is critical for erections, so it helps you get it up. Second, it helps germ cells and young sperm divide properly, therefore increasing count.
Because it is generated by the body, most people have sufficient L-Arginine. Athletes often supplement L-Arginine because it is reputed to support the release of Growth Hormone which supports muscle development. Most studies show that this isn’t true. They have shown, however, that supplementation of L-Arginine is effective for reducing blood pressure. This could indicate that it would be useful for reducing erectile dysfunction. Studies have also shown a positive correlation between L-Arginine supplementation and sperm health, but most of those studies involve fertility supplemental blends that contain a number of key nutrients essential for sperm production.
Bottom line: L-Arginine probably not an effective supplement. Your body makes all it needs, and it is highly available in most animal based food sources.
What it is: An amino acid generated by the liver and kidney that helps break down fats and convert them into cellular energy. It also has antioxidant properties enabling it to serve many important functions at the same time.
How it works: All cells contain mitochondria which are responsible for generating energy for the cell. Inside the mitochondria there are a number of enzymes and proteins responsible for breaking down energy that we receive from food. L-Carnitine is an amino acid that helps transport various fats through the mitochondria to be broken down into small molecules that the mitochondria can use to power the cell. In addition, the molecular structure of L-Carnitine enables to it bind to ROS and radicals making it also an antioxidant.
How it helps fertility: Cellular division requires a lot of energy. Germ cells in the testicles are constantly dividing to form new sperm. With decreased energy, they are not able to divide as well or as rapidly. L-Carnitine also helps ensure baby sperm are safe by protecting them from ROS an radicals which could interrupt their development.
What it is: Selenium is a mineral that is found in the ground that is primary used for making glass and electronics. In large doses, it is toxic, but in small doses it is an essential nutrient vital for normal endocrine processes as well as providing protection against certain environmental pollutants.
How it works: Like many key nutrients, Selenium does a couple of things. First, it is involved in a number of thyroid processes which help regulate hormones in the body. Second, it has strong antioxidant properties. Third, it plays a critical role in the structural development of sperm.
How it helps fertility: The thyroid plays a critical role in setting your metabolism and determining how sensitive your body is to various hormones. In men, poorly functioning thyroid glands can lead to an increase in prolactin which can interrupt the hormonal signals for proper sperm production. Selenium helps with a number of molecular processes within the thyroid to ensure that is functions properly.
Another role selenium plays in strengthening male fertility is it actually supports the structural integrity of the sperm by reinforcing the neck piece that connects the head and tail. Stronger necks enable more sperm to maintain motility, live longer and swim better.
Because of the important structural role that selenium plays in sperm, in cases where there is a selenium deficiency the body prioritizes its role in the thyroid and in sperm, lowering concentrations in seminal fluids. Reduced selenium conctration in semen has been shown to correlate with reduced motility. This again is due to its role as an antioxidant which protects sperm from reactive molecules in semen and helps them live longer.
What it is: Also known as ascorbic-acid is commonly used as a preservative to prevent fresh foods from oxidizing (think of apples turning brown). This molecule is essential for a number of cellular processes. For this reason, most animals have the ability to produce it. Humans and monkeys however have lost this ability and therefore need dietary sources to ensure proper functioning of the body. Vitamin C deficiency causes scurvy.
How it works: Vitamin C plays important roles all over the body. Among other things, it is used by the liver and kidneys to generate critical amino acids including carnitine which can play an important role in sperm production. Like more of the molecules listed, vitamin C is an antioxidant and deals with the waste products of cellular energy creation. It is also a pro-oxidant which helps remove excess metals and toxins and improve the absorption of certain minerals. It strengthens the immune system’s ability to respond to infection and surprisingly is a natural antihistamine.
How it helps fertility: Vitamin C does a lot to keep you healthy, which in itself goes a long way in promoting fertility. It also specifically promotes sperm health through enabling the creation of key amino acids required for sperm production (such as carnitine). It also protects sperm against a number of internal and external toxins which in turn improves motility, morphology and DNA integrity.
What it is: A fat-soluble vitamin that is naturally produced by many plants.
How it works: Fats are broken down into smaller pieces to create energy for cells. During that process, small pieces of reactive oxygen species (ROS) are expelled as a by-product. This is a similar process to how fuel is burned for energy. Small molecules of carbon monoxide are left over and expelled as part of the reaction. Because vitamin E is fat-soluable it easily mixes with fats and is nearby when they are converted into energy. Its molecular structure allows it to bind easily to several ROS molecules at once and safely carry them away, keeping them from damaging surrounding cells.
How it helps sperm: The process of creating and maturing sperm takes a lot of cellular energy. Additionally, as mentioned above, sperm are swimmers and therefore use more energy than typical cells. Because of this, there is a high need for antioxidants to keep sperm production high and keep sperm healthy.
What it is: The 24th most abundant mineral found in the earth’s crust which is commonly used in batteries and combined with copper to produce brass. Zinc is an essential mineral for human health and nearly 2 billion people suffer from zinc deficiencies which can cause retardation, delayed sexual maturation, susceptibility to infection and diarrhea.
How it works: Zinc forms the base of nearly 100 specific enzymes in the body which means that is one of the chemical bases that our bodies are built out of. Zinc is distributed all over the body but the highest concentrations are in the eye, the prostate and semen demonstrating its critical role in men’s health.
How it helps sperm: Zinc is critical for male fertility in many ways. It helps with the synthesis of folate which is critical for DNA production. It is also a building block of testosterone, semen, the prostate and even sperm themselves.
Reactive oxygen species and sperm function–in sickness and in health. Aitken RJ, Jones KT, Robertson SA. J Androl. 2012 Nov-Dec;33(6):1096-106. doi: 10.2164/jandrol.112.016535. Epub 2012 Aug 9.
Oxidative stress and male infertility–a clinical perspective. Tremellen K. Hum Reprod Update. 2008 May-Jun;14(3):243-58. doi: 10.1093/humupd/dmn004. Epub 2008 Feb 14.
Tissue physiology and pathology of aromatase. Stocco C. Steroids. 2012 Jan;77(1-2):27-35. doi: 10.1016/j.steroids.2011.10.013. Epub 2011 Nov 13.
Male factor subfertility: possible causes and the impact of nutritional factors. Wong WY, Thomas CM, Merkus JM, Zielhuis GA, Steegers-Theunissen RP. Fertil Steril. 2000 Mar;73(3):435-42.
Male infertility: nutritional and environmental considerations. Sinclair S. Altern Med Rev. 2000 Feb;5(1):28-38.
Impact of folate and homocysteine metabolism on human reproductive health. Forges T, Monnier-Barbarino P, Alberto JM, Guéant-Rodriguez RM, Daval JL, Guéant JL. Hum Reprod Update. 2007 May-Jun;13(3):225-38. Epub 2007 Feb 16.
The importance of folate, zinc and antioxidants in the pathogenesis and prevention of subfertility. Ebisch IM, Thomas CM, Peters WH, Braat DD, Steegers-Theunissen RP. Hum Reprod Update. 2007 Mar-Apr;13(2):163-74. Epub 2006 Nov 11.
Coenzyme Q(10) in male infertility: physiopathology and therapy. Mancini A, Balercia G. Biofactors. 2011 Sep-Oct;37(5):374-80. doi: 10.1002/biof.164. Epub 2011 Oct 11.
Polyunsaturated fatty acids in male and female reproduction. Wathes DC, Abayasekara DR, Aitken RJ. Biol Reprod. 2007 Aug;77(2):190-201. Epub 2007 Apr 18.
Lafuente, R; González-Comadrán, M; Solà, I; López, G; Brassesco, M; Carreras, R; Checa, MA (Sep 2013). “Coenzyme Q10 and male infertility: a meta-analysis.”. Journal of assisted reproduction and genetics 30 (9): 1147–56. doi:10.1007/s10815-013-0047-5. PMID 23912751.