TestoFuel Blog : Make Gains & Pack on the Muscle
So far in this series, we’ve looked at all the positive changes you can make to your lifestyle in a bid to support healthy testosterone production. In this article, we will be taking a different route, instead of looking at things to avoid.
It is important to note that many of the testosterone killers in this article are perfectly safe and that a complete and utter ban is often unnecessary. Alcohol is a good example, in very large doses it can ruin testosterone, but when taken in moderation it is absolutely fine.
Frank conversations about testosterone can often descend into hysteria among gym-goers, and that is not the intent of this article. Other articles use terms such as “dangerous” and “avoid at all costs” and many state opinions as facts. Because of this, we will first take a look at testosterone killer myths and debunk them.
While there are a lot of foods and products that may harm testosterone, many of the most commonly cited testosterone killers actually have no effect either way. Here are some common myths debunked.
Open up ten articles on testosterone killers and you can bet that nine of them will mention the fact that watching too much pornography lowers testosterone. This is a complete myth, but an understandable one.
There is certainly evidence that too much pornography can affect libido and cause erectile dysfunction, but this is not due to testosterone. There is no clear link between erectile dysfunction and low testosterone [1]. The cause is psychological or due to poor blood circulation.
Pornography can affect how your brain works, and can certainly lower sexual desire, but it will have zero effect on testosterone production.
A lot of men, often older ones, talk about the feminization of society. How there are no more “real men” these days and that this is due to a lack of manly jobs. This myth comes about because people confuse masculinity and testosterone.
Firstly, masculinity is a social construct, not a scientific one. Two men could have completely different definitions of what a real man looks like, and they both could be right. Because it is their definition. It doesn’t matter what they believe, because having a manly job, wearing manly clothes, or participating in manly sports has no influence on testosterone production.
How much testosterone you produce is influenced by your genetics, how much sleep you get, how healthy you are, and your diet. Changing jobs from shirtless lumberjack to cross-dressing burlesque dancer will have absolutely zero effect on testosterone production.
That being said, jobs that are outdoors and involve a lot of exercise are often healthier and may help to support testosterone levels. But it is not due to the jobs themselves, an overweight bricklayer who drinks 6 pints per night is not likely to have higher testosterone levels than an accountant who exercises regularly and eats kale five times per week.
We’re not sure where this myth sprang from, but it’s certainly an interesting topic. There are absolutely chemicals in some foods that can lower testosterone (we’ll cover these later), but the idea that just because a food is processed or not organic it will cause low testosterone is absolutely not true.
It is often a good idea to avoid foods that are highly processed, as they are often very high in calories, sugar, and “bad” fats. But very few processed foods will influence your testosterone either positively or negatively. The fear of chemicals is irrational, as even the healthiest foods around are made of chemicals! How scary does dihydrogen monoxide sound? But it’s just water (H2O).
As we mentioned in the introduction, many articles on testosterone killers could easily be mistaken for articles on serial killers! The language used is often alarming, and very sensational. But how important is it to avoid them in the grand scheme of things?
This really depends on the individual. If you exercise regularly, sleep well, eat a diet that supports healthy testosterone production, and know how to manage stress, then you are unlikely to be affected by testosterone killers. Your personal testosterone production will be good enough to protect you from them.
However, if your testosterone production is low, due to any of the above factors, then these testosterone killers could exacerbate the problem. Chances are, that anyone reading an article on hidden testosterone killers is probably concerned about low testosterone, so it could be beneficial for you to avoid the following things. But if you put most of your energy into improving your sleep, exercise, diet, and keep stress to a minimum then you’ll get the best results.
Here are ten hidden testosterone killers, though not all should be treated equally. Drugs, for example, are obviously best avoided, while mint tea which may well lower testosterone can still be enjoyed in small doses without much risk of testosterone loss. Use your own judgement where applicable.
Sounding like the monster from Alien, xenoestrogens are a form of xenohormone. A xenohormone is a hormone that is created outside of the body but mimics the function of hormones such as estrogen and androgens. The name comes from the Greek word ξένος (xenos) which means stranger.
Most of the xenoestrogens that harm humans come from plastics, but they can also be found in pesticides (see #9), herbicides, and preservatives.
There is evidence that xenoestrogens can affect testosterone levels, however, the evidence is mixed. There is certainly evidence that xenoestrogens can affect the testosterone levels of fish [2], and they also appear to affect rats, but there have been no studies on how xenohormones affect humans.
A 1997 survey of scientists found that only 13% believed that xenohormones should be of major concern, while 62% thought it should be a minor concern [3]. The scientific consensus appears to be that the levels of xenoestrogens that the average human is exposed to in their lives are not enough to cause low testosterone.
However, you should still be careful with how much you are exposed to them. Xenoestrogens can be found in BPA (chemical used for water bottles, canned foods, toiletries), PBB (chemicals used to prevent plastics from burning), and PCBs (manmade chemicals that are used for insulation and to prevent fires). You also have phthalates that can be found in vinyl flooring, medical devices, as well as perfumes, lotions, and makeup.
If you are involved in the production of any of these products then you are more likely to be exposed to xenohormones. However, the risk of a plastic bottle of water affecting your testosterone is fairly low. Use glass bottles instead if you want, but this is more of an environmental thing than a health issue.
Natural xenoestrogens are known as phytoestrogens, and they are found in plant-based foods. They should not be grouped together with plastic or pesticide-based xenoestrogens though, as they are very different. While there are no redeeming qualities of exposure to plastic or dangerous chemicals, there can be many benefits to consuming phytoestrogens.
Soy contains a number of natural phytoestrogen compounds, and there is certainly evidence that it can lower testosterone levels in men. However, soy also has many health benefits, helping to reduce the risk of colorectal and prostate cancer [4].
The problem with the phytoestrogens in soy is that they can disrupt the natural testosterone/estrogen levels in men (and women for that matter). It’s not so much that they lower testosterone, but that they affect the ratio of testosterone to estrogen [5].
You may be wondering whether this is much of a big deal, how much soy do you even consume? Well, the problem for non-vegans is that soy is often fed to livestock, and sadly the phytoestrogens found in soy can be transferred into the meat that you eat. We’ll talk about meat more later (#8).
Again, it is important to stress that eating foods containing soy are unlikely to cause a healthy man to lose testosterone. But if you are already overweight, already suffering through stress, and rarely exercise, then reducing your soy intake could help.
The way some men talk, you would think that every sip of beer you have is another percentage drop in testosterone. Luckily, it doesn’t work like that. Moderate or low alcohol intake has no effect on testosterone. But heavy drinking can definitely lead to low testosterone.
Alcohol affects testosterone in the same way that cortisol affects testosterone. Affecting the release of gonadotropin-releasing hormone, inhibiting luteinising hormone, and disrupting testosterone production in the testes.
Drink alcohol every day, and you can expect to see a reduction in testosterone production [6]. Drink alcohol a couple of times per week, and you are unlikely to see any change.
In this section, we are focusing on illegal drugs, because obviously, there are legal drugs that can raise testosterone. We will take a brief look at anabolic steroids, but the focus of this section is more on regular illegal drugs.
Anabolic steroids are rarely described as testosterone killers because they are responsible for massively high testosterone levels in bodybuilders. But that’s only in the short term. The long term effects of anabolic steroids are to disrupt your body’s natural testosterone production. Meaning that overall, anabolic steroids could be considered natural testosterone killers.
Marijuana is one of the most commonly taken drugs, but sadly it also contains phytoestrogens, specifically Δ9-Tetrahydrocannabinol. Some studies have found that it can lower testosterone and reduce fertility in men [7]. One Danish study found that marijuana use actually increased testosterone, but that it also reduced fertility [8].
Cocaine doesn’t appear to affect testosterone in men at all, though it does increase testosterone levels in female rhesus monkeys [9]. However, cocaine can affect sleep, which can then lead to reduced testosterone in the long term. Narcotics such as heroin appear to significantly lower testosterone levels in addicts [10].
Basically, try to avoid the use of dangerous drugs as not only can they kill you, but they can also lower testosterone!
Vegetable oil (also called canola oil) appears to negatively affect testosterone levels in men, as does soybean oil. A 2010 study on rats found that both forms of oil led to significantly lower testosterone levels [11], probably due to the phytoestrogens contained within.
Another reason could be that many forms of vegetable oil are high in polyunsaturated fats, which include omega-6 fatty acids. These have been shown to harm testosterone production [12]. A 2000 study on Japanese men found that those who ate more polyunsaturated fats had lower testosterone levels [13].
While the polyunsaturated fats in vegetable oils can lower testosterone, it is the trans fats in junk food that provide the worst effects. Studies have found that trans fats can lower testosterone and negatively affect sperm count in healthy young men [14].
Trans fats are found in foods that contain partially hydrogenated vegetable oil, but luckily, they are becoming much rarer as more and more countries ban them. Check your food labelling, and if you see the words partially hydrogenated vegetable oil, then avoid it!
There are many herbal remedies that can support testosterone production, so don’t see this entry as an attack on herbal medicine. However, due to phytoestrogens, there are some herbal remedies such as mint and liquorice that can lower testosterone.
A 2003 study on healthy men found that taking liquorice root saw an average drop in testosterone of 26% [15]. Mint has similar effects on rats, but there is no evidence (so far) that it affects men in the same way.
Don’t take this to mean that you should avoid liquorice and mint entirely, just don’t consume them every day, particularly if you are already low in testosterone.
There are a few reasons why non-organic meat, particularly in the US and Canada, can lower testosterone. Many livestock is fed soy to help bulk them up cheaply, and this is passed on to humans. Preservatives can also affect testosterone, as they contain xenoestrogens, and the pesticides that are used to grow the crops eaten by livestock can also contain xenoestrogens.
This is why organic meat is a better choice, though it is more expensive. Grass-fed cattle will contain fewer xenoestrogens than grain-fed or soy-fed cattle, they also tend to live happier lives, which has absolutely nothing to do with testosterone but is a nice little bonus.
As with the previous entry, non-organic fruit and vegetables are more likely to contain synthetic xenoestrogens than organic fruit and veg. This is due to the use of pesticides and herbicides to remove unwanted insects and weeds and boost crops. Considering many fruits and vegetables already contain natural xenoestrogens, this could be doubly bad.
The worst offenders are slowly being phased out and are increasingly rare. But not everywhere. If you are particularly worried about losing testosterone from xenoestrogens, buy organic where possible.
You eat right, you sleep well, and you have avoided alcohol, drugs, and cheap meat. Yet you barely walk 1,000 steps per day. A sedentary lifestyle is a huge testosterone killer. Increased body fat, reduced muscle mass, and a lack of exposure to sunlight all contribute to lower testosterone. As time goes on, more and more of us are becoming sedentary, and finding ways to avoid this will really help.
All of the testosterone killers on this list are scientifically proven to lower testosterone. That’s why we included them. However, we do not wish to exaggerate their effect. It is unlikely that drinking bottled water is going to significantly affect your testosterone. Nor is it likely that eating a cheap hamburger is going to fill your body with phytoestrogens.
If you ate a cheap hamburger every single day then it probably would, but you would be more likely to suffer from low testosterone because that hamburger led to weight gain. The tenth testosterone killer on our list (a sedentary lifestyle) is by far the biggest cause of low testosterone.
By all means, avoid drugs and alcohol (for a variety of health reasons), and where possible avoid cheap foods that seem to suffer from the most xenoestrogens. But don’t react to a cup of mint tea like it is poison. Because it isn’t. The biggest testosterone killers are sustained weight gain, stress, inactivity and bad sleep.
References
[1] https://pubmed.ncbi.nlm.nih.gov/7192541/
[2] https://academic.oup.com/toxsci/article/78/1/156/1625636
[3] https://pubmed.ncbi.nlm.nih.gov/9527611/
[4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6104637/
[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4270274/
[6] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6571549/
[7] https://pubmed.ncbi.nlm.nih.gov/18328619/
[8] https://pubmed.ncbi.nlm.nih.gov/26283092/
[9] https://pubmed.ncbi.nlm.nih.gov/26283092/
[10] https://pubmed.ncbi.nlm.nih.gov/1123724/
[11] https://pubmed.ncbi.nlm.nih.gov/20930468/
