The gut plays an extremely important role in testosterone optimization.
A few reasons how the gut (microbiome) can influence testosterone include:
- Recycling of hormones via beta-glucuronidase
- Deactivation of testosterone
- Lowing testosterone by producing inflammation due to leaky gut and endotoxin absorption
Relationship between androgens and the microbiome
The microbiome can influence your hormones and your hormones can influence your microbiome. Lowering testosterone or DHT can alter the microbiome and altering the microbiome can increase or decrease testosterone.
When male mice feces are transplanted into female mice, testosterone increase in the females. This suggests that specific intestinal bacteria promote testosterone production (R).
There are a few bacteria that can deactivate testosterone and cause depression. You can produce enough testosterone, but because of deactivation, you can still have low testosterone.
The liver attaches glucuronidase to hormones and creates, for example, testosterone glucuronide (TG). TG is then excreted in bile into the gut.
Approximately 80% of all steroids excreted in the bile get reabsorbed into the body (through enterohepatic circulation).
Beta-glucuronidase is the main enzyme (expressed by bacteria and inflamed intestinal wall) that removes glucuronide from testosterone and other hormones for reabsorption.
Using antibiotics that kill these bacteria causes a drop in free testosterone and DHT in the gut and subsequently, lower circulating testosterone and DHT (due to low absorption).
However, on the flip side, excessive beta-glucuronidation leads to excess estrogen reabsorption, which can lead to hyperestrogenism.
Giving pregnant women antibiotics led to a 60-fold increase in the fecal excretion of conjugated estrogens, highlighting the central role of the gut microbiome in modulating the reabsorption of estrogens (R).
Things that decrease beta-glucuronidase include:
- Milk thistle
- Konjac glucomannan
Things that inhibit beta-glucuronidase include:
- Bifidobacterium longum
- Sorbus leaf extract
- Apple pectin
Thus all of these things above should help to reduce excess estrogen reabsorption and improve the testosterone-to-estrogen ratio.
3β-hydroxysteroid dehydrogenase (3β-HSD) deactivate testosterone
3β-HSD expressed by certain bacteria, such as Mycobacterium neoaurum, degrade testosterone into androstenedione. This leads to reduced serum and brain levels of testosterone and induces depression-like behaviors (R).
83% (5/6) of the depressed patients, the feces can degrade testosterone into androstenedione (R). These results suggest that 3β-HSD expressed by gut microbes may be associated with depressive symptoms due to testosterone degradation.
Erythromycin is able to kill Mycobacterium neoaurum, thus inhibiting testosterone breakdown (R).
Other bacteria that can deactivate testosterone
Betaproteobacteria Thauera (specifically T. butanivorans and T. terpenica.) catabolize testosterone and can lower testosterone by about 50% (R). This bacteria can also decrease the abundance of Akkermansiaceae, Bifidobacteriaceae, and Enterobacteriaceae.
Clostridium innocuum and Clostridium paraputrificum can also deactivate testosterone (R).
Butyrate-producing bacteria and testosterone
Although I can’t find evidence in humans that butyrate itself boosts testosterone production, it can help indirectly, by lowering inflammation, preventing leaky gut, and calming the immune system.
Testosterone levels are positively associated with butyrate-producing members including Faecalibacterium prausnitzii, Roseburia intestinalis, Roseburia inulinivorans and the probiotic Bifidobacterium longum in men (R).
Vitamin B2 and Bacillus coagulans have been shown to increase Faecalibacterium prausnitzii (R).
Additionally, the prebiotic alginate oligosaccharide increased gut-beneficial microbes Lactobacillus and Allobaculum and elevate blood and/or testicular butyric acid, DHA, EPA, and testosterone in diabetic mice (R). So it would seem that, at least in mice, testicular butyrate correlates positively with testosterone.
This study in roosters found that sodium butyrate (SB) in doses of 500mg/kg increased testosterone (R). That, however, is a very large dose for humans.
These results suggest that sodium butyrate may promote testicular growth by increasing the antioxidant capacity and testosterone hormone secretion in adult roosters (R).
Endotoxin, leaky gut and testosterone
There are many kinds of toxins in the gut. These toxins are kept out of the body by the intestinal wall.
The mucosal surface of the gastrointestinal tract covers an area equivalent to the size of a tennis court, allowing for the very efficient transfer of food and water from the gut lumen into circulation. However, this also provides a large area of susceptibility for points of entry of harmful gut bacteria into the systemic circulation, where they can initiate activation of the body’s immune system.
Fortunately, the trans-mucosal passage of gut bacteria is normally prevented by several mucosal barrier defense mechanisms, including the production of a thick mucus lining that repels bacteria from the intestinal surface, bactericidal antibodies and immune proteins, as well as tight junctions between the epithelial cells that ideally prevent the passage of macro-molecules like endotoxin or intact bacteria between epithelial cells.
There are bacteria that degrade the mucus and cause leaky gut, thus stimulating the immune system and increasing inflammation.
When there isn’t a lot of mucus and you have leaky gut, endotoxin can pass through and cause inflammation that leads to low testosterone (hypogonadism) (R).
Things that can help to improve gut health are to:
- Remove foods that cause inflammation in the intestine (gluten, A1 casein, lectins, etc (it’s highly individual).
- Increase bifidobacterium. Bifidobacterium produces short-chain fatty acids (e.g. butyrate) that “feed” the host intestinal mucosa, and enhance the production of mucus and maintain tight junction barrier function. Low bifidobacterium numbers can result in a breakdown in intestinal barrier function and lead to low-level endotoxemia.
- Increase Akkermansia mucinophilia. Akkermansia mucinophilia has been reported to enhance the colon’s mucous barrier and result in a drop in systemic endotoxin levels.
- Increase Lactobacillus and Streptococcus. Some strains of these groups stimulate tight junction proteins (occludin, claudin-1) resulting in enhanced barrier function (R).
- Lower excess estrogen. Estrogen increases TLR receptors (receptors that are activated by endotoxins). Activation of these receptors increases inflammation (leads to IBS, IBD, etc.) and can contribute to leaky gut.
- Increase testosterone. Testosterone lowers TLR receptors thus improving the integrity of the intestinal barrier (R)
Furthermore, a recent randomized controlled trial reported a significant reduction in inflammation (high sensitivity CRP levels) in obese adults given a 3-month probiotic supplement containing bifidobacterium breve B-3 (R). Less inflammation can lead to higher testosterone, although testosterone wasn’t tested in this study.
Exercise, the microbiome and testosterone
Exercise can positively modulate the microbiome if done in healthy amounts.
According to this mouse study, high-intensity aerobic exercise increased the abundance of Akkermansia and Allobaculum, and also increased testosterone levels. The testosterone boost disappeared when the microbiome was wiped out with antibiotics. However, the benefits returned after doing fecal microbiota transplantation with the microbiome which led to high T (R).
Probiotics that can increase testosterone
Lactobacillus Reuteri on testosterone
Lactobacillus Reuteri has been shown to increase testosterone to youthful levels in elderly animals (R) and negate the testosterone-lowering effects of an inflammatory diet.
The strains that can increase testosterone are Lactobacillus reuteri ATCC PTA 6475 and BM36301 (R). Apparently, BM36304 is inflammatory.
The main mechanism of action seems to be by lowering IL-17, an inflammatory cytokine, and increasing IL-10, an anti-inflammatory cytokine (R).
This human study found that the probiotic Flortec increased testosterone from 721 to 860ng/dl and LH from 4.4 to 5.7 (R).
Flortec contains arabinogalactan 1243 mg, fructose 500 mg, fructo-oligosaccarides 700 mg, l-glutamine 500 mg, raspberry flavoring, non-soluble alimentary fiber 500 mg, Lactobacillus paracasei 86 B21060 <5 × 109 colony forming units (CFUs), black carrot amphocianines and Carthamus extract.
Flortec interacts with kisspeptin hypothalamic pulsatile secretion; regulating GnRH release. It likely also helps to reduce inflammation, which also improves Leydig cell function.
In diabetic rats, lactobacillus plantarum (R):
- Improved sperm motility and viability
- Improved testicular tissue development via increasing Leydig cell number, testicular spermatid count, and diameter of seminiferous tubules
- Increased testicular androgen receptor expression
This lead to higher testosterone and improved fertility.
In rats with high cholesterol, L. acidophilus ATCC 4356 improved testicular tissue and prevented the drop in testosterone (R).
However, in men, 3 billion units (109 CFU) of L. acidophilus and Bifidobacterium longum DDS® for 2 months did not alter testosterone, dihydrotestosterone (DHT), androstanediol glucuronide, androstenedione, dehydroepiandrosterone sulfate (DHEA-S), or SHBG (R). Their testosterone was around 490ng/dl on average.
Mega Acidophilus (a mixture of L. acidophilus, Bifidobacterium bifidum, and Lactobacillus helveticus) increased testosterone in rabbits (R). The mechanism of action appears to be by lowering oxidative stress and inflammation.
L. rhamnosus PB01 prevented the decrease in testosterone in mice made obese (R).
Gut health is extremely important for high testosterone.
To optimize gut health, we have to attack it from multiple directions. We have to optimize the diet to minimize gut inflammation and optimize testosterone at the same time. Since testosterone helps to reduce gut inflammation and improve the microbiome.
Then we can also use specific foods and supplements to reduce gut inflammation and re-modulate the microbiome.
To optimize gut health for high testosterone, we can focus on:
- Eating easy-to-digest food (undigested food can be converted to toxins by bacteria).
- Optimizing vitamin D levels by getting as much sunlight as possible. Probiotics and vitamin D have a synergistic effect on optimizing health and hormones (R). Read why vitamin D is so important for gut health. It’s not just about vitamin D. UVB light specifically also has a lot of benefits on the microbiome.
- Eliminating food that makes your gut health worse (e.g. gluten, high FODMAP foods, lectins, A1 casein, etc.)
- Exercising, as it can improve gut health
- Maximizing sleep quality
- Optimizing thyroid function. Optimal levels of thyroid hormones will improve stomach acid secretion, digestion and motility, all of which influence the microbiome.
Supplements that can help to improve gut health and increase testosterone:
- Vitamin D
- VSL#3 (it contains Lactobacillus, Bifido and Streptococcus that are positively associated with testosterone and negatively with inflammation)
- Natural anti-biotic-producing probiotics (use 1 of these; or the Phage with a spore probiotic)
You can always do a stool test (gut zoomer is very comprehensive or Biomesight that will look at your bacteria) to see what’s in excess or what’s missing and then address it from there.
>1000ng/dl Testosterone: My Step-by-Step Guide on How I Do It Naturally!