What's up, guys? Christopher Walker from Truth Nutra back again with another video. This video's going to be a good one, so definitely watch through it. I'm going to talk about some so-called health foods that are terrible for your hormones, specifically for testosterone.
If you're a dude and you care about your androgens, if you care about your testosterone levels, you might want to pay attention to this and implement some of this advice. I don't only just say things. I actually have a lot of research to back it up. Let's go through the list. First up, we got flax seeds, then we got protein, mint, licorice, vegetable oils, soy, wine, and nuts. This is the list. I'm going to back all this up with research. It's not my research. It's just research that researchers have done out there, and we've compiled it for you so you can see it all. I don't just say random stuff. It's all backed up.
First up, flax seeds lower your testosterone levels. They're actually pretty terrible for you, so you should definitely stop eating them. Why, you might ask? It's actually because they're very high in lignans, and lignans are extremely estrogenic. They're very estrogenic. There's also evidence that they reduce testosterone and DHT activity, which is not surprising considering how estrogenic they are. In this study, the researchers actually used to lignans to drive estrogen higher. That's how well-known it is that the lignans in flax seeds are estrogenic, that these researchers actually used it to make estrogen higher, to purposely lower testosterone levels in a woman with polycystic ovarian syndrome. Basically, what happened in this study was that they lowered her testosterone levels by 70% and her free testosterone by 89%, so it's pretty effective. You probably should avoid flax seeds. Some people get their panties in a bunch about flax seeds. They're like, "Oh, I love flax seeds." I don't get it. They don't taste good. Why would you care about flax seeds? I mean, a lot of people think they're healthy, "Oh, the omegas," and whatever, but they're super estrogenic. Why would you be eating them?
Second up on the list, protein intake is inversely correlated with testosterone. I thought this was really interesting, but it is very logical. It actually makes sense. Some researchers have done studies on looking at the correlations between different manipulation of macronutrients, i.e. protein, carbs, and fats, with relation to androgen levels. What they found was, again, some logical correlations. The biggest one was basically that the higher percentage of protein that a subject consumed as part of the daily caloric intake. We're not talking about an unlimited calorie intake. Say you're going to eat 2,500 calories a day. The higher percentage of protein intake, the lower the testosterone levels were across the board. This was very reliable and replicable. As you can see here on the charts on the screen, they're just looking at serum testosterone levels in the first chart versus the protein-carb ratio. Basically, the higher the protein was relative to carbohydrates, and the same was true with fats, the lower the testosterone levels were. The line graph on the right side is also indicative of the percentage of protein as a ratio there. That's really interesting because you also see in a lot of research with bodybuilders, as bodybuilders are dieting before a show, I mean they have these massive drops in testosterone. Most of their intake typically comes from protein at this period of time, and then they're also in a caloric deficit, kind of a double whammy.
Third on the list is mint lowers testosterone. I was actually super surprised when I found this out. I like mint. I think mint tastes good. It seems like one of those benign things that you would never guess, but let's look at the research behind it because this stuff lowers testosterone drastically. It's insane. In this study, they basically looked at Leydig cells and testicular tissue in rats' hormone levels with mint teas. They looked at SFH, as well, and LH. What they found was that the rats that drank the 20 grams per liter of peppermint tea decreased their testosterone by 23%, and then the rats that drank the spearmint tea decreased their testosterone, at the same volume, decreased their testosterone by 51%. Insane. Spearmint seems to be worse than peppermint when it comes to this, but both of them significantly decreased. You might be saying, "Oh, I don't care about rats," because that's what everyone says when they see a rat study. Rats, a lot of times, are helpful. It's helpful to see another mammal. However, there's also human research. In this one, they found that... They were having this woman drink this, I think, because she had this condition called hirsutism, where she has high testosterone levels and, as a result, grows body hair and that sort of thing. Again, it's kind of like that flax seed study where they purposely had this woman drinking the spearmint tea. They saw an average drop in free testosterone of about 30% in five days. They had 21 females that all had this condition doing this, and the average was 30% in five days, which is very significant and important to know because a lot of people drink mint tea before bed.
Some people like licorice, other's don't. I know Ali does, and in the Scandinavian countries they love licorice. It's a staple flavor. I, personally, am not a huge fan of licorice. It's kind of a weird flavor. The thing is that the main ingredient in licorice that gives it that flavor is called glycyrrhizic acid, and the glycyrrhizic acid is quite potent on blocking testosterone production in the Leydig cells. Here's a rat study of Leydig cells, and then basically they showed how it almost completely blocked testosterone production. Then in this New England Journal of Medicine, they looked at it in human men, obviously, that consumed licorice and also saw... In just four days, they saw 50%, or almost a 50% drop in testosterone levels. The average subject in this study went from about 740 nanograms per deciliter down to 484 nanograms per deciliter testosterone. Again, this was four days of eating, and they were eating commercially-available licorice, stuff that you could go to the store and buy, so take note of that.
Next up on the list is vegetable oils. They lower both testosterone and thyroid function. Anybody who's a fan of Ray Peat also knows this. He talks a lot about it with regards to metabolic function and thyroid, but it also has a significant effect on testosterone. A lot of people have been taught if you just sort of pay attention to the mainstream nutrition, mainstream health advice, that vegetable oils are healthy. They are farthest from healthy that you can get in terms of fat. Saturated fat and monounsaturated fat is plenty healthy, and those are the ones that are demonized, which is insane. The vegetable oils, the polyunsaturated fats, they have weak bonds, and they're very easily broken, denatured, with light, heat, oxygen. All that will denature these bonds, and they become toxic in the body. Again, this was the study from earlier looking at macronutrients. In general, it found the following findings, but the big one was that the increased intake of polyunsaturated fats across the board decreased testosterone levels. They saw that total fat intake would boost testosterone if it came from saturated and monounsaturated fats, but when it came from polyunsaturated fats, it lowered testosterone levels.
Next up on the list, and this is a pretty common one, soy lowers testosterone levels. There's all sorts of competing research. A lot of the research out there is also sponsored by ... The pro-soy research is sponsored by the soy industry or vegetarian-vegan-type stuff. However, there are a couple problems with the soy. It's estrogenic, goitrogenic, and anti-androgenic. There's research to prove all of that. First up on the list is estrogenic. It contains a high amount of compounds called isoflavones, which are phytoestrogens. They basically exert estrogenic effects on the body. The main isoflavones in soy are Genestein, Daidzein, and Glycitein. They've been shown in research to actually activate estrogen receptors. Next, the goitrogens. Basically, that's the impact that soy has on the thyroid in terms of being anti-thyroid and anti-metabolic. The main goitrogenic impact is by interfering with iodine uptake in the thyroid gland. Even if you're not iodine-deficient, if you're consuming a lot of soy and the goitrogens in soy are going to interfere with the iodine uptake, in general, and you're going to have a poorer-functioning thyroid. Also, I mean, a poorly functioning thyroid has been found to be one of the leading causes of low testosterone in men anyway. Then the anti-androgens, it's basically going to directly suppress testosterone and DHT production. The main ingredient that's known to do that in soy is called equol. Equol basically forms in the gut when the bacteria try and metabolize one of those isoflavones, Daidzein. What happens is equol is formed and it basically down-regulates androgen receptors. You don't want to mess with soy at all anyway. Again, it doesn't taste good. I don't know why people like it.
Number seven, drinking wine lowers testosterone. It's like a conditional thing. Alcohol, in general, has a dose-dependent effect on your testosterone levels. In lower amounts like one, two, maybe three servings, depending on your body weight, you're actually going to see either a slight acute rise in testosterone levels or no effect really. However, when it goes beyond that, what happens is it starts to put your body into a state of stress and you see a drastic drop in testosterone production. Then they also found in studying alcoholics, that alcoholics, in general, have much higher estrogen and much lower testosterone than regular and social drinkers or non-drinkers.
Last but not least on the list, another controversial one. I did a video on this here on this channel if you want to go look for more details on it, but nuts. Not all nuts. There are some nuts which are fine, and I talk more about in that video. That video, I mean, has almost got a million views now. A lot of people get kind of pissed off about it, but I'm literally just talking about the research that's out there. Some of the main highlights in that video are how almonds and walnuts increase SHBG levels, which SHBG is a sex hormone binding globulin. It binds to testosterone, makes it inactive, and that basically is going to reduce the bioavailability of the androgens, testosterone, and DHT. A lot of nuts are super high in polyunsaturated fats, in general, which we talked about lower testosterone levels and increase oxidative damage. Most nuts are actually very high in phytosterols. Some people think this is a benefit, but it's really not. They also interfere with steroid hormone production.
Comments will be approved before showing up.