Are you feeling symptoms of low testosterone even though your total testosterone is high?
Low free testosterone and low or clogged up androgen receptors can cause feelings of low testosterone.
The free fraction of testosterone is what binds to androgen receptors, and if you have low of both, you’re bound to feel as low as ridden over roadkill. It doesn’t feel good.
Testosterone, once released from the testes is bound to albumin and SHBG. Albumin, which binds about 33–54% of the released testosterone is like a good chauffeur that escorts you around but doesn’t restrict you from doing what you want to do. Testosterone is only loosely bound to albumin and can “break” loose and still bind to androgens receptors.
SHBG, which binds about 44–65% of the released testosterone and is like a clingy jealous girlfriend. SHBG binds much more potently to testosterone than albumin and is very hard to disassociate from.
So only about 2-5% of testosterone is free (R). If SHBG is elevated and total testosterone is low, free testosterone could be around 1%. Not where you want it.
5% of the free testosterone is then converted to DHT via the 5-reductase enzyme, and in a healthy situation, only about 0.2% is converted to estrogen via aromatase. That number goes way up when the aromatase is stimulated by things like inflammation, polyunsaturated fats, stress, etc. You want more DHT and less estrogen.
When you’re doing a blood test, check for both total testosterone and SHBG. High SHBG might be ok if your total testosterone is high because then your free testosterone will still be high, but if total testosterone is mid-range and SHBG high, you might experience symptoms of low testosterone.
SHBG isn’t just jealous, it’s unfaithful too. It goes after your most potent androgen, DHT, and binds to it with the 5 times greater affinity than to testosterone. SHBG binds the strongest to DHT and the weakest to estrone. Highest to lowest affinity looks like this: dihydrotestosterone (DHT) > testosterone > androstenediol > estradiol > estrone. DHEA is weakly bound to SHBG as well, but DHEA-S is not. DHEA-S is the storage form of DHEA in the body.
However, SHBG isn’t useless in the body and it’s not just there to make your androgens unavailable. SHBG prevents testosterone clearance from the body, prolonging its half-life in the body and prevents the conversion of testosterone to androstenedione (a weaker androgenic metabolite that much more prone to aromatization that testosterone itself). SHBG also increases the uptake of androgens into cells as some cells express SHBG receptors. For instance, SHBG potentiates the anti-tumour effects of testosterone in the prostate. When SHBG is bound to testosterone, it’s able to bind to the SHBG receptor and is then transported into cells.
Additionally, you don’t just want to indiscriminatingly lower SHBG because you feel low testosterone. Do tests first. Some people might actually already have low SHBG, such as people with inflammation (R), low estrogen, hypothyroidism (R) or hyperinsulinemia and hyperglycemia (R).
Symptoms low free testosterone include:
- Hypogonadal symptoms even if total testosterone is normal (R)
- Elevated LH
- Low libido
- Low physical function
- Slow walk speed
- Low energy
- Struggling to add lean mass and strength
- Struggling to lose fat and adding the pounds easily
- Struggling to get or maintain an erection
- Hair loss
- Hot flashes
- Low bone density
- Insulin resistance
- Testicular shrinkage
- Trouble sleeping
- Brain fog
- Low confidence, feeling you’re not getting out of life what you want
Let’s dive into it. How do we lower it? You’ve done the tests, you definitely have low free testosterone, what do you do?
#1 Eat protein
Protein intake is negatively correlated with SHBG, meaning: meat-eaters tend to have much lower SHBG than vegetarians (R).
If you think that protein is bad for testosterone, you need to read this post right here. It’s very much needed to build muscle and to keep testosterone high.
Even sedentary people need about 100g of animal protein daily just for basic bodily functions. If you lift weights, that number goes up to 150-200g daily. To avoid consuming an excess of the inflammatory amino acids, methionine, cysteine and tryptophan, get about 10-30% of your total daily protein from gelatin. So something like 100-120g animal protein and 30-50g gelatin. Although gelatin is very low in leucine, it potently stimulates hypertrophy and boosts fat loss.
#2 Do exercise
All kinds of exercise are able to increase free testosterone, such as slow pace cardio, moderate-intensity cardio, high-intensity interval training, lifting weights, doing calisthenics, hiking in the woods, surfing, rock climbing, etc. (R, R).
If you want the best bang for your buck, do short and explosive exercises either with bodyweight or with weights. Explosive exercise, especially against high resistance, is the best for boosting testosterone and free testosterone.
Things like hill sprints, muscle-ups, jump squats, heavy deadlifts and squats, etc.
But as with anything, don’t overdo it. Overdoing cardio or weight training will lower your thyroid, testosterone, IGF-1, increase cortisol and inflammation and your free testosterone will drop.
Interestingly, drinking a bit of alcohol (a glass of wine) post-workout will result in significantly higher free testosterone (R). But don’t overindulge, as high alcohol consumption lowers T and significantly increases SHBG (R).
#3 Reduce fibre intake
Fibre is a guilty booster of SHBG. High fibre intake is a craze getting high praise in scattered places around the interwebs, so if you’re under that crazy, get out.
Fibre does have its benefits, but an excess, especially if it’s from supplements, and if you have bacterial overgrowth, can wreak havoc to your body.
Fruit fibres actually have a lot of health benefits and the amount of fibre in fruits is relatively small. So if you want to consume fibre for health, get it from fruits. But just beware, some fruit fibres, such as from banana, apple, pear, etc., can also cause digestive issues for some people. So just eat fruit with their fibre that you tolerate well.
Bottom line, the more fibre you consume through your diet, the more SHBG you’ll have (R). I have consumed a fibre-free diet for quite an extensive period of time as an experiment and I had no constipation or digestive problems.
But as a standard guideline, around 10-20g fibre daily from good sources should be more than enough.
#4 Growth hormone & IGF-1
Growth hormone is secreted when insulin is low, which is usually during the night or during a fast. Eating boosts the conversion of GH to IGF-1 and GH drops and IGF-1 peaks after you’ve eaten a nice meal.
GH and IGF-1 seem to be two polar opposites due to one being high during a fast and the other being high due to feeding.
Administrating GH, either though GH injection or peptides, will increase GH levels in the body and reduce SHBG. But…GH also lowers testosterone (R). As a result, free testosterone is unaffected (R). One way GH might increase free testosterone is when it increases insulin levels. Insulin lowers SHBG, not the GH.
One thing to be wary of is that GH can promote insulin resistance because it promotes the release of fat from fat stores and this cause an increase in insulin. The greater your lipolysis operates, the greater your chance of becoming insulin resistant. Anything that blocks lipolysis, such as aspirin, lowers insulin requirements and improves insulin sensitivity.
IGF-1 injections, on the other hand, improves insulin sensitivity and lowers insulin levels (R). This is good if you are insulin resistance, but too much can cause hypoglycemia, and this will skyrocket SHBG.
GH boosting peptides, such as hexarelin or ipamorelin can increase IGF-1, but this effect vanishes with ageing and with insulin resistance. Given the GH might make insulin resistance worse, using GH analogues is not a good idea in my opinion.
Rather focus on boosting IGF-1 through natural means, such as colostrum, vitamin D, DHEA, zinc, magnesium, protein, egg yolks, milk, etc.
#5 Avoid lignans
Flax seeds are the greatest source of lignans, while other foods such as:
- Seeds from pumpkin, sunflower, poppy and sesame
- Nuts, particularly cashew nuts
- Whole grains, such as rye, oats and barley
- Bran from wheat, oat or rye
- Fruit, such as green grapes, cloudberries, grapefruit, oranges, tangerine, apricot, melon, pear and kiwi
- Vegetables, such as broccoli, Brussel sprouts, Cauliflower, red & white cabbage, kale, sweet peppers, tomato, cucumber, zucchini, green beans, carrots and potatoes.
…also contain a considerable amount.
But don’t freak out about avoiding these foods. There are 8 different lignans and you might react differently to each one. For example, you might do well on citrus fruits, but react negatively to apples. It could just as well be the pectin instead of the lignans. So just keep a level head about this and become conscious of which food give you a negative reaction and which don’t and then stick to those that give you no negative reaction.
But the two biggest ones I would keep away from is flax and sesame.
#6 Build more muscle
This means that fat mass lowers SHBG due to promoting inflammation and insulin resistance, and this is not the drop in SHBG that you desire.
On the other hand muscle mass correlates with the free testosterone index (R). If you want muscle mass, increase free testosterone and if you want free testosterone, exercise. It’s a positive feed-forward cycle.
Someone that is very overweight will experience an increase in total testosterone and free testosterone when they go into a deficit and lose weight.
However, the leaner someone becomes and the longer they do the deficit and the bigger the deficit is, the great the chance they stand to experience a drop in testosterone and an increase in SHBG.
Losing weight has to be done safely to maximize testosterone and free testosterone and not harm the metabolism along the way.
If you want to lose weight, check out my article on the uncommon things to focus on that really matter:
#7 Increase leptin
Leptin lowers SHBG (R), increases testosterone production, stimulates the metabolism, promotes fat loss, reduces hunger, etc. It’s a great hormone to have.
Low carb diets lead to low leptin (and insulin) and this increases SHBG, which can lower free testosterone. However, this isn’t necessarily a bad thing as low SHBG can contribute to prostate cancer, metabolic syndrome, atherosclerosis and even cardiovascular health (R, R, R, R).
Fat cells secrete leptin and people with lots of fat secrete tons of leptin. However, they are leptin resistant and don’t benefit from the leptin, but the leptin still lowers their SHBG regardless if they’re resistant or not.
The key would be to reduce fat mass, lower total leptin, increase testosterone (testosterone increases leptin and promote fat loss) (R), lower inflammation and hyperinsulinemia and leptin will drop and become more sensitive.
#8 Stimulate insulin
Glucose is the most insulinogenic, whereas fructose is the least. If you are sensitive to high GI foods, such as white rice, white potatoes, etc., eat fruits, milk and dried fruit instead as they don’t overstimulate insulin and actually improves glucose disposal and insulin sensitivity.
Just keep in mind that low GI carbohydrates can actually increase SHBG while high GI carbs lower it (R). It might be that low GI vegetables are high in fibre and that it causes a very low insulin release, while high GI foods are low in fibre and cause a spike in insulin.
Monosaccharides (glucose or fructose) effectively decrease SHBG expression by inducing lipogenesis, which reduces hepatic HNF-4alpha levels, a transcription factor that plays a critical role in controlling the SHBG promoter (R). Don’t worry about getting fat from carbs, as only 3-5% of carbs are converted to fat, while the rest is being burned for energy or stored as glycogen.
#9 Lower estrogen
Estrogen significantly increases SHBG production by the liver, whereas androgens such as testosterone and DHT decrease it. Your body produces all the SHBG as a defence mechanism to deal with the high estrogen, so a simple method to lower the SHBG that’s binding to all your DHT is just lower estrogen (R).
Even phytoestrogens, such as those found in legumes (soy, chickpeas, mung beans and alfalfa) and nuts (almonds and pistachios) are guilty here as they increase SHBG production and SHBG gene promoter activity (R).
Three main categories of phytoestrogens include:
- coumestans (found in alfalfa and clover sprouts, and sprouted legumes such as mung beans and soy sprouts)
- lignans (found in flax, sesame, grains and vegetables)
First, avoid phytoestrogens and second, lower excess estrogen.
#10 Increase DHT
Androgens such as testosterone and DHT lower SHBG. The way testosterone lowers SHBG is by converting to DHT. DHT is actually the main suppressor of SHBG. Research shows that when boys were given HCG (which stimulates the testes to produce testosterone), their SHBG dropped, but only if it converted to DHT. Boys with the 5-alpha reductase deficiency did not experience a drop in SHBG (R).
Testosterone can either increase SHBG (by boosting estrogen) or lower SHBG (by boosting DHT).
#11 Promote thyroid function
SHBG is elevated during hyper- and lowered during hypothyroidism (R). Don’t try to stay close to hypothyroid as then your androgen production will suffer. Testosterone and DHT synthesis is significantly increased during hyperthyroidism.
Although SHBG is elevated by thyroid hormones, the ratio between testosterone/DHT and SHBG is even higher so that you end up with more free testosterone than during hypothyroidism.
#12 Lower PPARγ
PPARγ is a receptor, that, when activated, increases SHBG production and promotes fat storage (R). Potent natural PPARγ agonists include polyunsaturated fat and estrogenic foods. Soy and red clover have the most potent agonism as they are the most estrogenic. Estrogen increase PPARγ expression and androgens decrease it.
So that is it for creating the optimal foundation for high free testosterone. Now let’s discuss supplements.
#1 Vitamin D
This sunshine vitamin increases testosterone & free testosterone. But only if you have a vitamin D deficiency. The testosterone difference is quite significant when having adequate vitamin D levels vs being deficient. Men with sufficient vitamin D levels also had significantly lower SHBG than deficient men (R, R). So I would highly recommend getting some sunlight instead of a supplement, but if that isn’t possible, a supplement is highly valuable. More on vitamin D here…
- Vitamin D – 1000IU per serving, 180 servings
Boron is somewhat of a rare mineral to consume and our diets are relatively devoid of it. And even if we do consume some of it, it’s usually around 1-3mg daily. Research shows that 10 mg of boron supplementation results in a significant decrease in SHBG and an increase in free testosterone (R).
If you plan on using boron, use 10mg, as 2.5mg of boron daily had no effect on androgens (R).
- Boron – 3mg per cap, 250 caps
Magnesium can be used as a sport enhancing aid and is positively correlated with total testosterone. Additionally, magnesium inhibits testosterone from binding to SHBG (R, R),. Magnesium doesn’t necessarily lower SHBG, but only inhibits it from binding with testosterone.
It’s quite hard to consume 100% of your daily value of magnesium through foods alone due to lots of anti-nutrients in foods, low concentration of magnesium present in the food or due to the body excreting it rapidly due to being low in energy. Leafy greens, cocoa, milk, tubers and some fruits are good sources of magnesium. More on magnesium here…
- Magnesium glycinate – 200mg per serving, 113 servings
Oysters would be the best source of zinc, 100g of oysters contain 524% of your DV of zinc. Second best is red meat 48% of your DV of zinc from just 100g.
- Zinc glycinate – 22mg per serving, 250 servings. Start with 1 serving twice daily.
Iron is also shown to be positively correlated with total testosterone and free testosterone (R).
I don’t recommend getting a supplement as iron is highly reactive with oxygen and makes free radicals and causes damage. Oxidative stress, driven by excess iron, is one of the major reasons for low testosterone and testicular damage.
Rather consume iron-rich foods. Vitamin C helps with iron absorption whereas vitamin E and caffeine reduce iron absorption. Vitamin E, vitamin C, melatonin and flavonoids, polyphenols and other beneficial compounds in fruit protect against the toxic effect of iron.
The best source of iron would be beef liver, as 100g would give you 99% of your DV of iron.
Dairy (cow, goat or camel dairy products) is the best source of calcium and is also rich in lots of other nutrients, such as vitamin A, B2, B5, B12, D, zinc, selenium. Dairy also has a great macro-nutrient composition for testosterone production.
In this study, people who consumed the most calcium had the highest testosterone, free testosterone as well as the lowest estrogen.
The calcium from dairy products is the most bio-available. Eggshell powder is also a great source of calcium. Just ½ a teaspoon is all you need the day.
Although forskolin is mainly used as a fat-loss supplement, which does work (mildly), it also boosts testosterone a bit by increasing cAMP.
As seen here, individuals who ingested 250mg of 10% forskolli (25mg forskolin) twice a week increased their free testosterone by 16% after 12 weeks, while the placebo group saw no change.
- Forskolin (40% extract) – 25mg forskolin per serving, 60 servings
#8 Tongkat Ali
- Tongkat Ali (200:1 extract) – 100mg per serving, 60 servings. Start with 100mg twice daily. (Lost empire herbs)
- Tongkat Ali (100:1 extract) – 400mg per cap, 150 cap (South African orders only)
DHEA (dehydroepiandrosterone) lowers SHBG and increases free testosterone (R). However, under a stressful condition, DHEA is mostly aromatized. I recommend using small amounts, between 5-15mg daily. When applied topically, a large amount is converted to DHT due to the high expression of 5-AR in the skin. DHEA combines very nicely with pregnenolone, progesterone and/or androsterone.
- DHEA – 10mg per cap, 90 caps
- CortiNon – 3mg progesterone & 1mg DHEA per serving, 360 servings
- Androsterone – 1mg per serving, 360 servings
Progesterone decreases intracellular SHBG, which might partly contribute to the abolition of the intracellular estrogen-dominant milieu (R). Since both DHEA and progesterone lower SHBG and have a great synergy, why not use them together? Add extra androsterone for more DHT as DHEA and andro also synergizes.
- Progestene – 20mg progesterone per serving, 30 servings
- CortiNon – 3mg progesterone & 1mg DHEA per serving, 360 servings
#11 Black Musli
Black Musli, at doses of 50mg/kg significantly increased free testosterone in rats (R). The human equivalent dose would be 7.1mg/kg. So an 80kg man would have to consume 570mg daily.
#12 Stinging Nettle & divanil
Stinging nettle inhibits the binding of DHT to SHBG, and the lignan, divanil ((-)-3,4-divanillyltetrahydrofuran) showed the greatest affinity (R).
- Divanil – 700mg per cap, 150 caps (South African orders only)