Total Fertility Rate Declining: 3 Large Contributing Factors to Male Infertility

It's a fact that fertility rates have been declining for almost a century, pretty consistently. Sperm is much easier to evaluate, and 50% of infertility is attributed to the male, so this article will focus on the declining sperm counts and quality. Keep in mind though, these same factors impact female fertility as well. I will discuss, in my opinion, three large contributing factors to decreasing sperm viability. These are: widespread dietary fads, specifically low fat diets, pesticides, and plastic contamination.

Reality of the Problem

Sperm counts in 1940 averaged 113 million/mL, and today (2019) that average is 49 million/mL. That is almost a 50% decline in about 80 years. This should be a serious public health concern, if you ask me, but it doesn't seem to be. Well, it's concerning to me, and if it continues this way, the future does not look very good. Another halving of the sperm count in 80 years would lead to the average being critically close to the low end range of conventional normal of 20 million/mL. Keep in mind that number is not optimal, optimal sperm counts are >75 million/mL. So, yes, that is correct, we are already averaging well below optimal.

The most important thing to look at in regards to these alarming statistics is, WHY? Why are sperm counts decreasing at such a fast pace, and what can we do about it? I tend to take a big picture approach on a topic like this. What has changed in the last 80 years?

Diet Fads

One of the biggest nationwide shifts, that happened just after the 1940s, is the introduction of the low fat diet. This, is in my opinion, one of the worst diet trends in history. Cholesterol is the backbone of all steroid and sex hormones, and without adequate and good quality fat, hormones like testosterone, estrogen, cortisol, and progesterone will suffer. Healthy fats in the diet are also important in forming healthy cell membranes. Cell membranes are the outside layer of all your cells, and yes, that's right, both sperm and eggs need to have healthy cell membranes too! Every day there are cells in your body that divide and create new cells. Healthy fats need to be in your diet to ensure the membranes of these cells are healthy.

Pesticides

Another big change during this time was the introduction of widely used commercial pesticides on our food and sprayed in our environments. It is well studied that consumption of pesticides is linked to a decrease in sperm count. This article describes 15 pesticides and their impact on male fertility. Not only do these chemicals impact the sperm count, but also the shape and the ability for the sperm to swim effectively, which is necessary for the sperm to reach the egg for fertilization.

Plastics

Plastic usage became widespread in the 1950s. There is some research about the impact of micropastics and plastic in general impacting male fertility, however the data on this topic is not as abundant as other areas. This does not mean it should be disregarded. Research is interesting, some topics are simply more challenging to set up a good quality study for, and sometimes certain topics have just not been studied as throughly. Nonetheless, just because we haven't researched it as throughly, it is not grounds to dismiss it as a possible contributing factor. We are always learning, and in my opinion, innocent until proven guilty is not a good approach when it comes to your health and fertility. The reason plastic should be suspect of fertility implications is because it is well established that it impacts other animals reproductive capabilities, why would humans be any different?

Microplastics are the byproduct of plastics that have broken down from litter, and even broken down from processing making their way into the ocean and into air pollution. Plastic has been shown to disrupt hormones, and in animal studies disrupt sperm quality. Microplastics can be found in human waste, so we know it is getting into our bodies, usually through consumption of seafood, inhalation from air pollution, and contaminated water, including drinking out of plastic and eating out of plastic especially when heated.

Conclusion

So there you have it, three major contributing factors to decreasing male fertility: low fat diets, pesticides, and plastics. It is important to note that while this article focuses on male infertility, these same factors contribute to female fertility as well. Becoming aware of your environment and changing what you can, can have measurable impacts on your fertility.