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Does Onion Boost Testosterone Levels?

To optimize your testosterone levels you’ll need to take a good look at your lifestyle – are you in the gym lifting weights? Are you using a natural T-boosting supplement?

If you answered yes to both of these questions then you’re halfway there already.

Hopefully, you’re aware that diet is a massively important part of any strength, conditioning or physique building program too. You could work no end in the gym, but if your diet isn’t on-point then you’re wasting your time.

In this article we’ll take a look at the humble onion. Could this versatile vegetable be the key to optimal hormones?

Let’s take a look…

The Testosterone Battle

As men reach the age of thirty their testosterone levels begin to gradually slip – around 1% each year.

Before you know it you’ve lost your muscular frame, you feel weaker and your sex life is non-existent. And that’s why you’ve got to do all you can to fight the hormone battle and keep those levels high.

Both training and diet are fundamental is this fight; and research suggests that some foods are better at giving you the advantage over others. This is where onions come in.

Onions and Health

Allium cepa or onion bulb, is a vegetable characterized by it’s distinctive, pungent taste and aroma. Native to Asia, this food is used in a number of different cultural cuisines – from French to Mexican cuisine and pretty much everything in-between.

It is one of the most commonly consumed vegetables in the world. Onion production has increased by at least 25% over the past 10 years with current production being around 44 million tonnes per year. This makes it the second most important horticultural crop after tomatoes.

Onion has long been used for its beneficial effect on disease treatment worldwide. They are low in calories and high in vitamins B and C. They provide fiber as well as a range of minerals including potassium, calcium and magnesium.

Onions are also high in amino acid sulfoxides. You’ll know this if you’ve ever chopped one. It’s the compound that’s responsible for making you cry when it reacts with water in your eyes!

Onions are High in Antioxidants

This vegetable is high in antioxidants – particularly flavonoids, a type of polyphenol. They are basically an all-rounder when it comes to boosting your health and well-being.

Polyphenols help to improve gut health and decrease the risk of a variety of cardiovascular and neuro-degenerative diseases. They can improve weight management too.


Whilst the darker red onion is high in the polyphenol anthocyanin, most varieties will provide you with another compound called quercetin – a powerful antioxidant with anti-inflammatory properties.

In fact, behind tea leaves, onions are one of the best sources of this compound you’ll find. Review studies have shown that it can reduce fatty acid absorption and free radical damage, as well as protect against a range of  different types of cancer [1].

“Onions are antithrombotic, hypolipidaemic, hypotensive, diaphoretic, antibiotic, antidiabetic, antiatherogenic and have anticancer medicinal properties” [2].

Onion as a Natural Testosterone Booster?

When you think of natural nutrients that optimize testosterone levels you might not necessarily think of onions. But research shows that they may play an important role in elevating T levels.

Improvements in male hormones

Khaki et al [3] found that in male Wister rats, onion juice administered over a 20-day period significantly increased testosterone levels – by a whopping 300%.

Not only that, but the 4 g per kg of body weight of juice also improved luteinizing hormone levels – a hormone responsible for stimulating testosterone production in the testes.

These improvements helped to boost sperm motility and concentration too.

Bigger testes

Although an old study, a research paper published in a 1967 version of Plant Foods for Human Nutrition [4] found that when rats were fed onion juice, the size of their testes increased by 25%. Their semen levels rose too – in both old and young rats.

Combing onion and zinc

A similar study [2] also used onion extract on male rats. This time they wanted to see how it pitched against well known testosterone-boosting nutrient zinc.

The research team gave the 162 rats varying orientations of the two nutrients. Some were given onion on it’s own, some were given zinc on its own, and others were given a combination of both nutrients.

The result? Testosterone was seen to increase in both the onion and zinc groups (zinc was higher) but even more significantly when the nutrients were combined.

Is Onion Juice the Way Forwards?

Let’s be right. Even though it’s cheap and accessible, it’d take a pretty hardcore person to glug down onion juice each day in the quest for bigger T scores.

And don’t forget – the research was conducted on rats not men, so caution has to be taken when transferring these results to you. Would you want to put yourself through the pain of drinking onion juice only to find out it doesn’t work? Of course not.

Better results?

Instead, you could save yourself the distress and go for well-researched nutrients like zinc instead. Remember, studies show that it is a great T-booster on it’s own, let alone when combined with onion juice. And just so you don’t miss out on the elevated luteinizing hormone, D-Aspartic acid (DAA) will raise your LH levels, similar to what onion juice does.

Enter TestoFuel

TestoFuel would be your best bet if you’re wanting to fuel up your T levels without having to put yourself through the torture of drinking onion juice.

If you’re really hardcore you could even wash TestoFuel down with the juice – but we’ll let you decide on that one!

As a top-of-its-game testosterone booster, TestoFuel gives you all of the natural nutrients needed to build a better body.


  1. Baghel, SS et al. A review of quercetin: antioxidant and anticancer properties. World J Pharmacy Pharmaceutical sciences. 2012; 1(1): 146-160 Ghalehkandi, JG et al.
  2. Effect of Onion (Allium cepa. Linn) Aqueous Extract on Serum Concentration of LH, FSH and Testosterone Compared with Zinc Sulfate Supplementation in the Rats. J Animal Vet Adv. 2012; 11(18): 2246-3349
  3. Khaki, A et al. Evaluation of androgenic activity of allium cepa on spermatogenesis in the rat. Folia Morphol (Warsz). 2009; 68(1): 45-51
  4. Sharaf, A et al. Some hormone-like properties of Allium Cepa L. (onion). Qualitas Plantarum et Materiae Vegetabiles. 1967; 14(3): 267-275