Low testosterone has been on the rise within the USA and the rest of the western world for some time, and whilst there have been notes to several lifestyle factors that may well be the cause, obesity, lack of sleep and stress the nutritional content of the Standard American Diet or SAD is a distinctly concerning factor. Several minerals and vitamins that impact testosterone production are now common deficiencies. It is of course important to address said lifestyle issues before implementing more serious options such as TRT.
The most notable inclusions are of course, vitamin D, Magnesium and Zinc.  Although there are several other factors at play, with a range of less commonly associated deficiencies, such as K2, B Vitamins and even minerals like calcium, omega fats and even micro nutrients like amnio acids and polyphenols commonly found in more commonly in diets 50 years ago potentially being a factor. The concern here is that when we polled the general population, 80% of men did not know that Vitamin D, Magnesium or Zinc deficiencies could cause low testosterone. Only 15% knew that any of them could cause this issue, and 90% estimated vitamin D deficiency as only effecting 10% of people where as the prevalence is closer to 50%.
When asked as to whether or not they thought they were likely to be deficient in one or the other around 30% said it was likely they were deficient in one or the other (mostly vitamin D), but less than 5% of the men over 30 thought it could be effecting there testosterone health.
Due to the prevalence of low testosterone in the general population, yet the high prevalence of people being treated for symptoms of low testosterone, it is quite possible that this is a silent epidemic, dramatically harming the mental health, sleep and physical fitness of men within the US.
And the culprit could be vitamins and minerals. As such we would suggest that much in the same way we advise the public on the need for calorie control, we should look to do more to inform men of this issue. It is likely that a lack of education on the importance of Vitamin D, Zinc and Magnesium is doing substantial harm. We would suggest that it is probably important to educate the population at large as to the rates of vitamin and mineral deficiencies in general as it seems likely that when presented with the numbers m
The Main Culprits: Which Vitamin Deficiencies Most Commonly Cause Low Testosterone?
Vitamin and mineral deficiencies, such as zinc, magnesium, and vitamin D, can disrupt what is known as the HPG axis. This can and does contribute to low testosterone levels. These nutrients play essential roles in testosterone production and overall hormonal balance. Several studies have shown that zinc supplementation in men with depleted levels can increase testosterone production and similar findings have been found for vitamin D and Magnesium.
Whilst these are the most well researched and seem to have the largest impact on the US population, due to them being relatively common deficiencies there are other vitamins and minerals which are required for the proper processing of these micro nutrients and other less common deficiencies which can also cause issues. To give some scale to the potential issue, around 1 in 6 American’s being low in zinc  and up to half of the population being low in vitamin D it is easy to see why this has been a cause for concern. 
Magnesium is also a relatively common issue at around 20-30% and some studies even suggeting up to 50% of American’s having a sub clinical deficiency.  Although sub clinical in context means no risk of serious issues, even these deficiencies can of course lower hormone production.
It Get’s Worse With Age: The Deficiency Rates In Older Populations
To make matters worse, many of these deficiencies are more common in older populations, with some studies suggestion that Vitamin D deficiency could be as high as 80% in over 60s, which is of course going to compound with testosterone’s natural decline with age. It’s also worth noting that black and Hispanic individuals are more at risk due to higher melanin levels meaning they don’t produce quite as much vitamin D.
At a certain point it could be suggested that the majority of the population that is naturally seeing declining testosterone rates actually has a deficiency that can make things worse.
What Other Vitamins Can Cause Issues?
So, we’ve covered the big 3 culprits, but what else can cause issues? Well, several B vitamins can and do effect hormone production, but they are relatively uncommon as deficiencies. Beyond that we have vitamin K2, specifically K2, which unfortunately does not currently have a separate RDI, despite calls for one. The issue is that K1 is not a common deficiency, but the bodies conversion of K1 to K2 is relatively poor, which results in many people not having enough of the variant. And it does have a place in hormone production. 
There are of course other vitamin deficiencies beyond these which can effect sleep, this in turn causes low testosterone. Calcium for example, whilst not directly implicated in causing low test levels, is more common in testosterone deficient populations and the reason for this is likely due to the fact that it’s deficiency effects sleep.
Beyond Vitamins and Minerals that cause low testosterone we have other micro nutrients. Amino Acids are the building blocks of protein. And there are several essential and none essential acids. This is generally not an issue for people who eat a variety of meats, but for vegans very few foods have a complete amino acid profile . Meaning that they have to get protein from a variety of sources to get everything they need. Vegetarians are generally fine if they consume whey, eggs or cottage cheeses regularly as they do have a complete profile. 
Omega Fats and Testosterone Levels
Omega’s play a role in a lot more than just the brain, heart and joints. As if that wasn’t enough of a reason for them to be a point of concern. This is of course another area in which a substantial part of the population is lacking. With the RDI being at 1100mg or EPA and DHA  (the type only found in fish, meat and algae, not in plants) certain populations are of course not getting nearly enough and the average American is also deficient. As we know stress reduces testosterone levels, omegas are required to reduce cortisol the stress hormone). And animal studies have gone on to show direct correlations,  although much of the human studies are ongoing, more and more evidence seems to show a link.
The Importance of Polyphenols
Polyphenols, found in various fruits, vegetables, and plant-based foods, have been shown to exert beneficial effects on testosterone levels. These compounds possess antioxidant properties and help reduce oxidative stress, which can negatively impact the HPG axis. Including polyphenol-rich foods in the diet may help support healthy testosterone levels. 
Other Dietary Factors Effecting Testosterone Levels
Caloric Intake and Testosterone
Research suggests that the calorific and nutritional value of a diet can significantly impact testosterone levels. For individuals with a healthy weight, a below-average caloric intake may lead to decreased testosterone levels. On the other hand, obese individuals may experience neutral or even positive effects on testosterone levels due to the same caloric deficiency. 
Addressing vitamin and mineral deficiencies through targeted nutritional supplementation can help restore testosterone levels. Supplements such as zinc, magnesium, and vitamin D have shown promise in supporting healthy testosterone production. However, it is essential to consult with a healthcare professional before starting any supplement regimen.
In addition to nutritional supplementation, making lifestyle modifications can have a significant impact on testosterone levels. Managing stress, prioritizing quality sleep, maintaining a healthy weight, and adopting a balanced diet rich in polyphenols can all contribute to optimal hormonal health.
Vitamins Role In Low Testosterone
Whilst age is the main factor in declining testosterone levels on a person to person basis. It has become quite apparent over the last few years that the average American’s diet is also a substantial issue. With obesity rates being as high as they are, and deficiencies in vitamin and minerals essential for testosterone production effecting over half of the population, it’s not exactly surprising that we’re seeing low testosterone levels rise.
As a result, it’s important to educate the general population on necessity of a healthy and balanced diet. And it may well be the case that many men currently following unhealthy diets may be more persuaded to take care of their nutrition, when it is presented in the context of something so intrinsically related to their “manhood”.
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8 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3880087/
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