What is the best protein for fertility?
Getting enough protein is an essential part of a fertility-friendly diet. As well as being the building block of muscle and tissues, we need protein to make enzymes, hormones and support the immune system. So, what proteins should we focus on to optimise fertility? Let’s take a look.
Evidence indicates that what you eat can be a powerful tool for enhancing both male and female fertility for anyone trying to conceive. In particular, research shows that a diet based on Mediterranean-style eating patterns, prioritising plants and lean proteins, omega-3 fats, fibre, whole grains, fruit and vegetables has a positive impact on female fertility, while a “western” diet high in trans fats, refined carbohydrates and added sugars has the opposite effect.
One of the key differences when comparing Mediterranean vs Western is the types of protein they encourage. While a Mediterranean-style diet emphasises plant-based protein, some seafood and minimal red meat, a “standard western diet” includes more processed meats and red meats, with fewer plant-based protein sources.
So let’s get into the research to determine which sources of protein can most effectively optimise your fertility, and which you should reduce or avoid to support your chances of conceiving.
What is protein?
First things first, protein is an essential macronutrient in any dietary pattern, alongside carbohydrates and fat. Protein plays many critical roles within the body, including supporting immune system function, muscle and tissue repair and growth, cell structure, and hormone production.
As you may guess, all of these roles means protein plays a crucial part in fertility and reproductive health too, in both men and women. If you’re not eating enough protein in your diet, you’re likely lacking other key vitamins and minerals such as iron, zinc, vitamin B12 and iodine, which are largely contained in protein-rich foods.
While many Australian adults get enough protein from their diet alone, in times of increased demand on your body (such as when you’re pregnant or breastfeeding!), or during stages of growth, your protein requirements increase slightly.
Why do you need protein?
Proteins are made up of a bunch of different building blocks, known as amino acids. The 20 different amino acids form different combinations to make various proteins with unique functions in your body. Some of these proteins are used to fight infections, some create enzymes needed for cells to function, some provide structure or support for your cells, while others transport signals throughout your body including hormones. So clearly, they’re extremely important for your body’s function.
One of the key roles of protein in supporting your fertility is their role in hormone transport, as naturally you need to maintain healthy production and transport of your reproductive hormones to allow you to fall pregnant. Without protein, this important function is compromised.
How much protein do you need each day?
According to the Australian dietary guidelines, adult women require at least 0.75 g of protein per kilogram of bodyweight daily, while adult males need at least 0.84 grams per kilo of bodyweight, although some research indicates that aiming a little higher than this to around 1g per kilogram of bodyweight may offer benefits.
Interestingly, if you fall pregnant you require even more protein, ideally between 1-1.5 g per kilogram of bodyweight or even slightly higher, highlighting just how important this nutrient is for yours and baby’s health.
At the same time, it’s important not to go too far overboard with your protein intake, as extremely high-protein diets during pregnancy can have negative consequences for foetal growth and also increase risk of anovulatory infertility, so there’s no need for *endless* scoops of protein powders and enormous servings at every meal!
What should you look out for in protein sources to support your fertility?
Stick towards the lower end of saturated fat content.
Consider the saturated and trans fat content of the protein choices you’re including in your diet. Studies have shown diets higher in trans- and saturated fats can negatively impact fertility, whereas higher intakes of monounsaturated fatty acids can have a positive effect on your fertility.
Some animal proteins including red meats, and cured or processed meats, tend to contain high levels of saturated fat, whereas plant-based proteins and lean meats such as fish, chicken and turkey contain lesser amounts of these fatty acids, making them a more fertility-healthy choice. If having red meat, choose lean cuts most of the time.
Avoid processed meats.
While we’ve covered the fact that processed meats have a high saturated fat content, they have a negative impact on fertility from various angles if you’re consuming them regularly.
Processed meats also contain harmful chemicals like nitrates, which are used to preserve these products, as well as trans fats which contribute to inflammation in the body - not a good thing for anyone looking to enhance their fertility!
Men who ate between 2 and 5 servings of processed red meat were found to experience a significant reduction in their sperm concentration, count and quality, and the men eating the most processed meat experienced 23% fewer morphologically normal sperm. Similarly, women who ate one additional serving of red meat per day were 32% more likely to struggle with ovulatory dysfunction, which significantly impairs your chances of conceiving naturally.Aims for additional nutrients present in your chosen protein sources that can further enhance your fertility.
By opting for protein sources which contain fertility-healthy nutrients, you’re giving your body a better chance of being able to support a healthy implantation and pregnancy when the time comes.
Some of these nutrients include:
Omega-3 fatty acids, found in in fatty fish (like salmon and sardines). Omega-3s support the production of reproductive hormones and reduce inflammation, thereby playing a significant role in optimising your fertility.
Iodine, which helps regulate your thyroid hormones and ovulation. Even more so, during pregnancy iodine plays a crucial role in foetal development and supporting your baby’s brain health and growth. Seafood, eggs and chicken are good protein sources of iodine.
Zinc has an important role in improving egg maturation, egg quality, fertility and pregnancy, and optimising sperm formation in men. It’s also crucial in allowing fertilisation to occur. Protein sources of zinc include lean red meat, chicken and beans.
Iron supports ovulation and fertility. In fact, studies showed women who used iron supplements were less likely to struggle with ovulation issues than those who didn’t. Iron-rich proteins include lean red meat, chicken, fish and eggs.
Strike a balance between animal and plant proteins.
As is clear from what we’ve already discussed, there are benefits to consuming some animal-based proteins and they can contain essential nutrients for fertility. However, excessive animal protein intake can start to have the opposite effect; what we really want to see is (i) a total protein intake within range and (ii) a balance between animal and plant based protein! One study found that swapping 5% of energy intake from animal sources of protein to plant-based sources saw ovulatory infertility risk drop by more than 50%.
That isn’t to say that you must go vegetarian or vegan if you’re wanting to enhance or protect your fertility. You can have protein of all varieties! But, consider adding in and diversifying with plant-based sources of protein such as tofu, lentils, beans, nuts and seeds.
In case it wasn’t clear already, when it comes to protein you’re going to support your fertility the best by aiming for variety!
Including a variety of different protein sources in your diet is key to optimising your fertility, as it helps you meet your nutrient needs for important fertility-supporting vitamins and minerals like iodine, zinc, omega 3 and iron. If you’re sticking to one or two proteins, you’re limiting your ability to obtain the variety of nutrients your body requires to make it a healthy environment for a baby to grow in.
Eating a range of both plant-based and animal proteins can help you mitigate the negative effects associated with specific proteins, while optimising your chances of meeting your protein and nutrient requirements at the same time.
So exactly what proteins are the absolute best for fertility?
We couldn’t wrap this up without giving some honourable mentions to a few fertility-friendly protein sources, and directly answering the question you came here for. So among the best protein sources for enhancing your fertility are:
Fatty fish
Fatty fish contain high levels of omega-3, which as we touched on play a key role in optimising your fertility and supporting production of sex hormones. Given how essential these hormones are in allowing you to fall pregnant, it’s no surprise that couples who ate fish twice weekly were much more likely to conceive than those eating fish less often. There’s some pretty exciting research which also suggests that omega-3s can help to maintain higher egg quality as we age.
Plant proteins
We’ve clearly established the incredible power of plant sources of protein in supporting ovulation and enhancing fertility. Some of the best plant-based protein sources to include are legumes, edamame, tofu and tempeh. Other plant foods like whole grains, nuts and seeds are also excellent nutritionally and can help you meet your protein requirements.
Now it’s time to add some protein to your plate. Remember, variety is key!
Need some support navigating dietary choices to optimise your fertility and chances of conceiving? Book a consultation with me to discover all the dos and don’ts of fertility nutrition, supplementation and lifestyle choices, to give yourself the best chance of growing your future family today!