Does fasting increase testosterone levels?

When it comes to your overall health, the hormone testosterone plays a pretty important role.

It’s involved in numerous bodily processes (think muscle growth, fertility, libido, mood and cognitive function) and not having enough of the stuff can lead to several negative side effects.

Several champions of intermittent fasting say that undertaking regular fasts can actually have a positive impact on testosterone levels, potentially helping to increase them.

But is the claim true? Let’s find out.

What is intermittent fasting?

Intermittent fasting is a type of eating pattern where you go through cycles of fasting and eating.

There’s no single length of time that each cycle lasts for; some people fast for several hours during the day — perhaps only having 2 meals, such as breakfast and dinner — while others might fast for a full 24 hours each week.

During a fast, your body starts to adapt to the lack of food.

At first, your blood sugar levels drop. As a result, your body turns to its glycogen stores (i.e. excess glucose stored in your liver and muscles) to fuel itself.

Once it has used those up, it turns to your fat stores for energy and starts producing ketones — acids that basically indicate your body is breaking down fats. You then undergo a hormonal shift, which ups the release of adrenaline and human growth hormone (HGH).

The idea is that increased use of excess glucose and fat helps stabilise your blood sugar levels and helps with fat loss, while the release of HGH can support further fat burning and muscle gain.

Intermittent fasting has become increasingly popular in recent years thanks to its many claimed health benefits (which we’ll get to shortly).

As such, while there’s no one way to fast intermittently, several prevailing methods have emerged. You might be familiar with some of them: 

• The 16/8 method, whereby you eat only within an 8-hour window and have a fasting period of 16 hours
• The 5:2 diet, where you eat your regular diet for 5 days of the week, then fast for the remaining 2 days — perhaps restricting yourself to a calorie intake of just 500-600 calories each day
• Alternate day fasting, where you eat one day, fast the next, and so on
• Eat Stop Eat, a method that involves fasting for 24 hours once or twice every week
• The Warrior Diet, which requires you to eat within a 4-hour window and fast for the remaining 20 hours
• One meal a day, where you only eat exactly that

Is there a link between intermittent fasting and testosterone?

Numerous intermittent fasting advocates tout the practice for its ability to boost testosterone levels. But does it really have any influence on your testosterone levels?

So far, experts aren’t entirely sure. The studies performed on the link between the two have produced incredibly mixed results.

Below, we’ll dive into this a little further.

Does fasting increase testosterone?

One study from 1989 backs up the idea that fasting increases testosterone, finding that the luteinizing hormone (LH, which is a key part of testosterone production) response went up by 67% and the resulting testosterone response by 180% after brief periods of intermittent fasting [1].

However, another more recent review from 2022 concluded that intermittent fasting decreases testosterone levels in young, healthy men, potentially negatively affecting their metabolic health and libido (but having no consequences for their muscle mass and strength) [2].

Others have echoed the same conclusion, while others still have found no bearing on testosterone levels through fasting.

It’s worth noting that each study varied quite significantly in the type of fasting implemented, the participants in the study and the methodologies used.

Plus, numerous other factors can influence the connection between the two, including the length and frequency of the fast and individual characteristics like genetics, age, exercise habits and lifestyle — all of which can affect someone’s testosterone levels.

All of this is to say that more research is needed in the space to firmly establish whether or not intermittent fasting can improve testosterone levels. 

Is fasting good for men?

If not to up your testosterone levels, are there any other health benefits of fasting regularly? 

There certainly could be. Here are some of its potential advantages.

It could help fight cancer

A 2022 literature review of 22 studies concluded that intermittent fasting had a pretty profound impact on numerous aspects of cancer treatment. 

It was able to tame the progression of cancerous tumours (including growth, metastasis and metabolic activity), improve cancer survival rates, and reduce the side effects of chemotherapy (such as organ damage and lower body weight) [3].

It may lower the risk of developing type 2 diabetes

A study from 2023 took more than 200 people with an increased type 2 diabetes risk and put them on different eating plans, one of which involved intermittent fasting.

After 6 months, those undertaking intermittent fasting showed greater glucose tolerance — potentially lowering their diabetes risk [4].

It’s worth noting, though, that they also experienced higher fatigue, constipation and headache.

It can fight inflammation

In 2019, researchers from Mount Sinai found that intermittent fasting can curb inflammation and improve the condition of numerous chronic inflammatory diseases — such as cancer, diabetes, heart disease, MS and inflammatory bowel diseases [5].

The reason why is that intermittent fasting lowers the release of inflammatory cells known as monocytes.

It could have weight loss benefits

A 2022 review of different weight loss studies compared intermittent fasting to continuous calorie restriction. 

It found that even though there was minimal difference between the two approaches when it came to lowering BMI among those with obesity or metabolic syndrome, intermittent fasting appeared to be more effective at reducing body weight [6].

It can improve cardiovascular function

Cardiovascular diseases are a huge problem and are the main cause of death around the world [7].

The category encompasses a range of conditions, including hypertension (high blood pressure), coronary artery disease, stroke and heart failure.

A literature review from 2019 examined several studies and concluded that intermittent fasting can limit many of the risk factors that support the development of cardiovascular diseases, such as body weight, blood pressure and inflammatory markers [8].

It may increase your longevity

Some research conducted on animals has found that extended caloric restriction (or intermittent fasting) can extend lifespan.

This is because fasting can encourage better blood glucose regulation, improved resistance to stress and lower inflammation. It also produces fewer free radicals (unstable atoms that can cause cell damage) as a result.

That being said, a 2022 paper stated that the effects of intermittent fasting on longevity really depended on the type of fasting undertaken, and in fact, some methods were found to decrease longevity [9].

Also keep in mind that despite the many health benefits of fasting, it’s not without its risks.

It has the potential to lead to nutrient deficiencies and overeating, as well as other side effects like headache, nausea, dizziness and insomnia [10].

Plus, as with its impact on testosterone levels, the research around the health benefits of fasting is still fairly mixed and more needs to be conducted to arrive at any definitive conclusion.

If you’re unsure whether intermittent fasting is an appropriate approach for you, reach out to a healthcare professional for tailored advice.

Tips for increasing testosterone levels

So, if not through intermittent fasting, how else can you boost your testosterone levels?

Fortunately, there are several ways to do so — and the majority involve easy-to-implement lifestyle changes.

Check your hormone levels

There are numerous signs of low testosterone, including fatigue, mood changes, a decrease in lean muscle mass, a drop in libido and erectile dysfunction (ED) [11].

If you notice any of these, make an appointment with your GP to have your hormone levels checked. You may very well have low testosterone, in which case your doctor can establish a plan to get your levels back up to normal.

And if ED is one of the symptoms you’re experiencing, Pilot’s ED treatment can help. In fact, 94% of men have been satisfied with the treatment and 78% have achieved lasting erections. 

Plus, the treatment is delivered right to your door in discreet packaging, automatically refilled every 2 months and includes unlimited free follow-ups with a practitioner. Nice!

Move your body

While your testosterone levels naturally vary throughout the day, research has shown that they do go up briefly after exercising [12].

Also, getting physically active 3-4 times every week — focusing particularly on weight and resistance training but also incorporating cardio — can help maintain a stable increase in testosterone levels [13].

Maintain a healthy diet

A nutritious diet is obviously a cornerstone of good health, but it can also affect your hormone levels. 

Some research has found that a diet high in foods like bread, pastries, dairy products and desserts, and low in homemade foods, noodles and dark green vegetables, can decrease testosterone levels [14].

At the same time, it could be worth limiting your alcohol intake. Some research shows that excessive alcohol consumption can actually decrease your testosterone levels [15].

Keep your stress levels in check

Research shows that chronic stress can lead to lower testosterone [16].

This is why curbing your stress levels can have a positive effect on the amount of testosterone in your body.

There are several great ways to manage stress, including exercise, eating well (which we know can both help boost testosterone), getting enough sleep, meditation and ensuring you take time out to relax. 

Get enough sleep

Poor sleep quality has been associated with decreased testosterone levels, so getting ample hours in each night may help support your hormonal health [17].

If you struggle with sleep, you can implement a few habits to try and improve it.

These include going to bed at the same time each night, sleeping in a cool and dark room, and avoiding stimulants like coffee, alcohol and screens close to bedtime.

Lose weight

Research shows that lower testosterone levels are connected to excess weight, particularly around the abdomen [18][19].

If you need to lose weight, you may find that doing so has a favourable effect on your testosterone levels. There are numerous ways to tackle weight loss, including through diet, exercise and lifestyle changes.

Struggling to lose weight? Consider jumping on board Pilot’s Metabolic Reset Program.

The program combines science-based treatments, health coaching from our in-house team of experts, an online community to boost your motivation and ongoing practitioner support to deliver a holistic and sustainable weight loss solution.

Try a supplement

You can also take a supplement that’s specifically targeted towards upping your testosterone levels.

Pilot’s Testosterone Support does just that, targeting the signs of low testosterone like ED, poor libido, decreased energy and mood fluctuations.

With a powerful combo of ingredients designed to help you regain your vitality, it has the potential to help you get back to feeling your normal, sturdy self.

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