No libido on carnivore diet? Here’s why!

Initially, carnivore/keto diets might make you feel amazing.

However, over time it might lead to issues, such as:

• Low libido
• ED
• Insomnia
• Anxiety
• Cold hands and feet
• No motivation and drive

How can something initially make you feel great, but then start to mess you up?

Here are 4 main reasons why a carnivore diet can cause low libido.

Insulin, SHBG and free testosterone

Carnivore diets are usually very low carb, since most people deem honey and milk not to be part of the carnivore diet.

Low-carb diets lead to low insulin.

Since insulin is the main suppressor of SHBG production, low insulin will lead to high SHBG.

SHBG binds up your testosterone and you’ll quickly see your free testosterone drop.

Often times you’ll see a massive increase in testosterone on a ketogenic and carnivore diet, yet experience low libido. This is because SHBG binds up a lot of the free testosterone and inhibits the negative feedback loop testosterone has on LH release.

Having low insulin isn’t necessarily a bad thing, but if it leads to low free testosterone, then it’s likely, not ideal for you.

Low libido despite high testosterone on low carb diet? pic.twitter.com/JXhrhyUKGX

— Hans Amato (@HansAmato) July 8, 2023

Carnivore diet on thyroid function and libido

Hypothyroidism and hyperthyroidism have been reported to contribute to low libido (R).

A low-carb diet lowers thyroid hormone production, mostly by inhibiting the conversion of T4 into T3 (R, R, R).

A few common signs of low thyroid hormone levels are cold hands and feet, cold intolerance and restless sleep. Combine that with high catecholamines (that I’ll talk about below), sleep is often short as well (5-6 hours) and you don’t necessarily feel tired even with short sleep.

Carnivore diet on cortisol

Cortisol has strong inhibitory effects on erections and libido. Up to 69% of men with high cortisol complain of low libido.

Although long-term studies have shown that there isn’t a difference in cortisol levels between people that do keto and those that don’t, they only looked at cortisol in the blood and not tissue cortisol.

One of cortisol’s main functions is to stimulate the liver to produce glucose from amino acids. If your carb intake is low, then the demand for glucose goes up. Although ketones can substitute for glucose to an extent, it cannot replace it completely.

An important marker to look at is intra-cellular cortisol, which you can’t see on a blood test.

The enzyme 11beta-hydroxysteroid dehydrogenase (11β-HSD) converts cortisone (inactive precursor hormone) to cortisol in the tissue that needs it, such as the liver (R). Excess cortisol production with 11β-HSD leads to insulin resistance, liver disease, central obesity (accumulation of visceral fat), catabolism of muscle, and much more.

11β-HSD is also expressed in the muscle, pancreatic islets, adult brain, inflammatory cells, and gonads, thus long-term low-carb diets can lead to reduced muscle mass, type 1 diabetes (destruction of the pancreatic cells), brain atrophy, and testicular shrinkage.

Low carb diets and fasting increases 11β-HSD and can lead to high tissue cortisol. If your fasting glucose is around 90+ even with no carbs in your diet, cortisol is elevated for sure.

Eating at least 100g of carbs or more will help to keep 11β-HSD and intra-cellular cortisol under control.

Many low carb-ers think that just because their serum cortisol is normal, they don't have cortisol issues.

However, they forget about intracellular cortisol, which is activated by 11β-HSD1.

Glucose is the main inhibitor of this enzyme. pic.twitter.com/gRP1cOhI5m

— Hans Amato (@HansAmato) July 8, 2023

Carnivore diet on noradrenaline and adrenaline

Noradrenaline and adrenaline are catecholamines secreted during stress or resource deprivation. One of the functions of catecholamines is to stimulate lipolysis and enhance fat and glucose oxidation. This is what should happen on a low carb diet.

In optimal amounts, these neurotransmitters improve our mood, stimulate motivation and drive, help with erections and focus and much more.

However, in excess amounts, they keep us up at night, make us feel wired, and can contribute to feeling jittery and anxious, give us rapid heartbeat, and can make us feel almost manic.

Initially, on the carnivore diet, a lot of people feel a surge in energy, motivation, drive, good mood, etc. But over time, they start to feel wired, anxious, jittery, unable to sleep, etc. Chronically elevated catecholamines can also make you insulin resistant due to excess stimulation of lipolysis.

Noradrenaline and adrenaline are also the primary anti-erection neurotransmitters (R). They work in a U-curve. In optimal amounts, they promote libido and erections, but in excess, they have the opposite effect (R).

Summary

A lot of my carnivore clients report a decrease in libido, despite having good energy and high total testosterone.

4 main reason for this is:
– Low free testosterone (due to low insulin and high SHBG)
– Low T3
– High intra-cellular cortisol
– High catecholamines

— Hans Amato (@HansAmato) July 8, 2023

To fix it, you don’t need to eat a lot of carbs. Aim for 100g to start with and then you can increase that over time as you get used to it.

Focus on easy-to-digest carbohydrates that don’t give you blood sugar rollercoasters.

Best carbs for the carnivore diet

A lot of people on the carnivore diet remove carbohydrates since they react negatively to them, specifically grains, beans and most vegetables.

Interestingly, a lot of people on the carnivore diet that I’ve talked to don’t get negative effects from honey, maple syrup and various fruits.

Everyone’s response to carbs will be different, so it’s important to experiment with one fruit at a time to identify if you tolerate it well.