Animal Stak Review- Why You Should Keep It Simple for Muscle…

Animal Stak Review and Results:

The Good:   Some good results. Big range of potentially good ingredients.

The Bad:  Possible side effects. Odd dosages. Complicated proprietary formula- Impossible to track. What is Animal Stak, & who makes it? 

What’s better than Stak?

Normally our website reviews testosterone supplements and boosters, and because of this reason, we HAD to take a crack at one of the oldest testosterone boosters on the market, Animal Stak.

Animal Stak is a well-known supplement in the body building industry, especially among gym veterans. It’s made by Universal Nutrition, which is a well known manufacturer, with a wide range of products.

Tons of bodybuilders and older folks at the gym will swear by Animal Stak, and rightfully so- the company has been around for 9 years, has a massive product line, and has great reviews as a supposedly do-all, catch-all, muscle builder and booster.

Editor’s Note – Travis, age 31, assistant trainer and ‘lifting enthusiast, reviews most of this article:  Honestly, I am a little skeptical of the product. As someone who is newer to the game of bodybuilding (less than 3 years in the iron game, but 10+ years in other sports) and getting those extra grinds and reps in the gym, I have my supplements and boosters that I really like…

(Note:  for a more technical analysis of Stak ingredients and effects on Post Cycling Therapy, see the FAQ at the end of this article– meant for more experienced “lifters” and “juicers”)

… some of my older mentors keep raving about it and are really trying to get me to give it a chance. Some of the veterans swear by this stuff. So I finally caved and decided to give it a good look and a chance.  

Animal Stak makes some bold claims about being so much more than just a testosterone booster. I am used to having to take a lot of different supplements to achieve the results I want, so something that advertises itself as a “complete anabolic hormone stack” is pretty attractive.

So my hope is going to be that Animal Stak will save me a few bucks, and give me the boost that all my previous supplement stack has been giving me. Save time, save money, give me more time to get in the gym and embarrass the old timers heh …

How good is this? Will it really work for you?  

That depends, will you work for it? Animal Stak will build muscle. That’s what this is all about after all. But YOU have to put in the effort to build that muscle. Animal Stak is nothing without getting those reps in and having the discipline to actually work out and dedicate yourself to body building and training.

Animal Stak 2 vs Stak 1- What’s the Difference? 

Editor’s note:  Unlike many earlier reviews, this one is for “Animal Stak 2” – though the company just calls it Animal Stak again. The formula has been revamped and apparently improved.

The first Animal Stak did contain steroid substances that were not legal in many countries. This new version removes or replaces banned substances (pro hormones) . Click here to check out buying options on Amazon.

Some die-hard fans of the brand love its long-lived “garage” feel, street cred and reputation. Stak has been around for more than 10 years… But we have to note that in the end they are still a big corporation/business  – and they do change their formula depending on their goals. Sorry guys, Animal is not God.

One of the things I like about Animal Stak is that it has been around for a while. It isn’t just a flash in the pan supplement. What I had been told about Animal Stak, about it not really working, well that was a different version of the formula from 7 years ago. So I thought to give it a chance: Who knows?

Who is it for?

Animal Stak really seems like they are just marketing to body builders. Forget other sports. This is supposedly for gaining muscle. This is for people who want to stay drug free and naturally build their muscles. Many of the folks who I talked to mentioned they really liked Animal Stak.

Proprietary Blend and Ingredients

But I am not so sure. My one big problem with Animal Stak is that they dont reveal exact dosages for their ingredients. This may be okay for some people, people who just like something that works.

But for me, I like to dig deeper, I like to know exactly what im taking, and how much of it. I need to know what I am putting in my body, and at that point Animal Stak falls seriously short.

And I get it, 10 years ago this may have been something that was okay, not giving exact ingredients and amounts. But its 2017: I’m tired of proprietary blends and putting shit into my body without knowing what it is  ;p

There are three ingredients I usually look for when buying a testosterone booster, and that’s D-Aspartic Acid, ginseng, and oyster extract, and Animal Stak has none of them. It really puzzles me that they don’t have these in the formula.  

Who is it NOT for?

I know Animal Stak doesn’t market itself as a testosterone booster, but that’s what I want to gain more muscle. And this just doesn’t have some of the proven ingredients that I want. And I don’t know how much is in it.

Being that it says it’s an “anabolic hormone booster”, and not JUST a testosterone booster, and I just need to see more testosterone boosting ingredients. So what’s funny is: if you are looking specifically for testosterone boosting, this may not be for you!

Animal Stak Online Reviews and Testimonials 

Being that Animal Stak has been around for so long, there is a lot out there about it. And people have both good and bad things to say about it.

Who is da bitch?

Elman says “I’m almost 60 and I’ve been using this product for the last 5 or more years off and on. I see the results every time I’ve used this product. Lots of good natural testosterone boosters, growth hormone, cell repair supplements in one complete stack.”

Dustyn adds “I wouldn’t say I noticed significant gains on this stak. However, I did notice that my energy levels during the work-out were increased and my strength was increased slightly when taking this supplement.”

Results and My Experience 

So here’s the deal, I took Animal Stak for a month. And I can agree with Dustyn that I did feel a small boost to my strength and energy. Animal Stak certainly did SOMETHING for me. I did feel an added energy and some added strength. I just didn’t see the definition that I was looking for.

Bottom line (at least in my subjective experience):  it does do something – just that I’ve felt much better before. And with no kind of listing of ingredients, it just wasn’t worth it. I feel like there are other testosterone boosters that  really help that I can trust more.

Overall, i’m sure when Animal Stak hit the streets all those years ago, it was an awesome product. But we have come far, and I expect more. Many old timers started body building with Animal Stak and will remain with it. But for me, I prefer something I know a bit more about. 

Animal Stak Ingredients Breakdown

The ingredient list for Animal Stak is pretty long and involved. And it certainly does have some products that have been proven to boost testosterone and help produce muscle.

Just glancing at the list, I see things pop out to me like Vitamin B6, magnesium, zinc, vitamin D-3, tribullus terrestris, fenugreek, L-Carnitine, arginine, etc…

And that’s not even everything. There are seriously a ton of ingredients in this stuff. Which when said out loud sounds really impressive. Like, oh the whole kitchen sink is in here.

And this is where my biggest gripe with Animal Stak comes in: they don’t list dosages of how much of an ingredient is included. So even though they include SOME clinically proven ingredients, they could be trace amounts that won’t actually help.

Ingredients:  How do they work?

 But i’m not a complete naysayer, so I can give credit where credit is due. There are SOME good things with Animal Stak. We are told the amount of ingredients that are in Animal Stak when it comes to zinc, magnesium vitamin B6, and vitamin D-3. Although this is looked at as a strength of Animal Stak, really it something I have come to expect from the boosters I take. So this is not so much going above and beyond, but the standard.

The ZMA (zinc, magnesium, & vitamin B6) blend within Animal Stak is one of the most proven blends to help boost testosterone levels.  The ZMA blend is known to boost testosterone. And all these other ingredients, if you are deficient in them, well then you will certainly see a boost. That’s to go without saying.

Vitamin B6 works as an energy booster.

Vitamin D-3 is particularly important for those who may be deficient in testosterone and CAN in some cases help boost testosterone.

L-Carnitine can help you from fatiguing and cashing out of your workout early.

Keep it simple.

Tribulus terrestris and fenugreek can help with libido, increasing sex drive:  But once again, they do not list the amount of these ingredients. So if you want to take Animal Stak and want the bonus of increased sex drive, who knows how much fenugreek is actually in there or if it will make a difference.

Risks and Effectiveness? 

These ingredients CAN certainly boost muscle production and COULD be highly effective, but we just don’t know how much of each ingredient is in there. So although they could be helpful, we don’t know that they will work for everyone because of lack of ingredient levels.

My personal preference is always going to be just to pick the exact amounts of the ingredients I want without having to take things I don’t need. 

But for me, the risk of not knowing what is in the product is too much. I need solid numbers, and I need dosage information for ingredients. And I need some clinical studies to back things up. (see the FAQ below for a more technical analysis)

User reports are a bit too varied for my liking, as well as for other accounts I’ve heard of. Some people talk about Animal Stak like a miracle booster, and some spend hundreds of dollars and report no change.

Side effects- Is Animal Stak safe? 

Some users have reported side effects to using Animal Stak. Those are:

  • Diarrhea
  • Acne
  • Pimples on the back
  • Long lasting erections
  • Difficulty sleeping at night

There have also been some reports of it causing severe acne.

How to take it? 

Animal Stak comes in an edgy animal looking tin, but opens up to show a number of bags of pills (which can be fearsome for casual users, as these look large and daunting). Hardcore, baby.

One advantage to Animal Stak is that you only need to take the pills according to the instructions provided – there’s no second-guessing what you should do. But keep in mind that you’ll be taking a large number of pills and you have to take them daily. You should take these pills 30 minutes before your workout. On your rest days, you should take them at night.

However, your body can adapt to the pills so you may get less effective results as time passes. Your kidneys and your liver may also be overloaded. That’s why you need to cycle your use of the supplement. You can take the pills for 3 weeks and then you have to stop for an entire week before you can begin another cycle.

What should I take it with? How do I stack with M Stak, Animal Pak, Animal test?

The company that makes Animal Stak, Universal Nutrition, has many other Animal branded products in their line they recommend taking Animal Stak with.

They especially recommend Animal Pak, a multivitamin that is said to work in harmony with Animal Stak. There are a number of other supplements in the Animal line that can be taken together. Frankly, we find most of them to be a bit unpredictable, loaded with proprietary formulas and scores of ingredients. (see the FAQ below if you are into more technical analysis’)

Where to buy Animal Stak 

Animal Stak is not hard to find, and can be purchased at many brick and mortar vitamin shops, as well as GNC, Amazon,

How long does it last? 

You can usually get a 3 week supply of Animal Stak for $35. That is 21 stak’s with 8 pills in each stak.              


  • Claims to help boost testosterone
  • Helps with sex drive
  • Can help build muscles in some cases
  • Has the zinc, magnesium, and vitamin b6 blend 


  • Proprietary blend, no exact dosages of ingredients
  • Missing proven testosterone boosting ingredients
  • Mixed reviews, some see no change, and some love it
  • No scientific studies
  • Massive dases, 8 pills at a time
  • Side effects can be rough, like bad acne

Animal Stak Results

Basically: you won’t notice a buzz like a pre workout formula, but you should notice increased strength and endurance during workouts, an extra rep or so in the first few weeks, gradually increasing into the months beyond. You should also notice increased libido and erections : )

Some users do report stimulatory effects 30-40 minutes after taking though, so you may want to be careful using this in the evenings.

Some users also report good results for body recomposition – though again we will note that proper recomp programs are usually meant for advanced lifters. That means improved vascualirity and definition.

Occasional reports of side effects are of oily skin or acne. Other hormonal imbalances may only show up over time if Stak is used carelessly – which may cause weakness in the long run. As for its “aromatase inhibitors” and DHT blockers, Stak is better used in combination with other supplements, by users who are more experienced with cycling and other plans (see FAQ below).


Here’s the deal: we don’t want to insult those who say Animal Stak works. But the claim that they are a “all-around anabolic hormone booster” without any clinical studies is concerning. And the average consumer doesn’t really know what that means.

But I’m not just going to take some supplement because of a fancy label and some big claims. I really would rather stay away from a proprietary blend, and focus more on things that I trust, and can read and trust the ingredients inside.

If Animal Stak works for you, great. But I will be looking into using more user-friendly, proven testosterone boosters.         

Frequently Asked Questions :“Cycling”, Animal Pak and Product Stacking, and more…

Is this suitable for Beginners and everyday use?  We would actually recommend a more versatile and safer test booster instead.

Experienced lifters (5 + years intensive training) will be pleased to know that users usually report obvious increases in strength, stamina and recovery – which in turn leads to greater gains.  This is an effective but complex booster meant to increase and support both testosterone and growth hormone levels and output. It contains anti-estrogenic ingredients, cortisol blockers, vasolidators, DHT blockers, and liver detoxification ingredients.

Many veteran lifters believe Stak is great for a post cycle therapy regimen. So we believe that Stak may not necessarily function at its best as a standalone booster and hormone “modulator”; it may need to be part of a more complex supplementation program.

“Is Post Cycle Therapy Really Necessary?”

If an athlete finishes an anabolic steroid cycle – yes. PCT helps ensure you keep muscle gained during the cycle. AND it prevents a post cycle crash that would destroy hard earned gains, as well as create a number of unpleasant hormonal side effects.

Please note that we do not advocate the use of “steroids”, but we do not intend to create a moral judgment on their use either. 

The most important element in a PCT program is restoring the body’s own ability to produce testosterone. You can’t expect your body to go into a temporary massive muscle boosting drive for 3 or 4 months and then, all of a sudden, go back to its normal self.

Disregarding the effects of such an hormonal imbalance could be dangerous. And that’s why steroid users need this therapy, to gradually get one’s body and hormones back to normal, and avoid extensive imbalances and side effects (balls shrivelling, crazy bad depression, and more  : )

Detailed Ingredients’ Breakdown– Aromatase Inhibitors, DHT, and more…

Here’s are ingredients contained in Animal Stak, and a basic explanation of why they were included:

  • Vitamin C, Vitamin B6, Magnesium, Zinc, Chromium. If you’re having testosterone problems, you may not be getting enough vitamins and minerals from your diet. These are the vitamins and minerals you need so that you can start boosting your testosterone production. Zinc especially, is a classic testosterone supplement.
  • Pro testosterone complex:   Tribulus Extract Complex, Longjack Extract Complex, Avena Sativa ExtractFenugreek, Stinging Nettle and Maca.   This is the Universal Nutrition Natural Test Complex. It’s a “proprietary” formula designed to encourage muscle building by stimulating your body to produce more testosterone.

Many of these are classic testosterone ingredients – some work more directly than others on testosterone, others are better for libido or stamina. This is likely to be a potent combination; however we can’t completely tell for sure due to its proprietary formula. We’re guessing the Pro testosterone formula here is fine, but other “complexes “ mentioned later are more obviously under dosed.

  • Growth Hormone Support: Arginine Alpha-Ketoglutarate, Arginine HCL. These are vasodilators; ingredients are meant to open your veins a bit wider so that blood flow becomes more efficient. By doing so, the nutrients you need are moved more efficiently to various parts of your body, including the protein to your muscles. It also increases blood flow to your brain, so that you can think better.

Arginine alone is typically supplemented in higher doses.  This blend is likely under dosed.   Mucuna Pruriens Extract, Alpha Glycerylphosphorylcholine (GPC). These ingredients help counter the mild depression (the “blahs”) and the reduced libido that often result from low testosterone. Alpha GPC is also good for alertness and focus.

  • Anti Aromatase complex:  Calcium D-Glucarate, Diindolylmethane. These are the aromatase inhibitors, and this means they block estrogen production. The simple explanation is: you have to maintain an optimum balance between your testosterone and estrogen levels. The testosterone should be kept high while these ingredients help keep the estrogen levels down.

But things may not be so simple because …

Aromatase Inhibitors: How do they work?

These are actually best after a cycle of pro hormones/anabolic steroids. There is usually an imbalance of hormones, which can take a long time to recover from – the duration of this vulnerable period leaves one open to bad side effects …

Yes this includes preventing bitch tits. (a.k.a “Gyno” symptoms) As well as water retention, high blood pressure and other issues.

Including aromatase inhibitors for post cycle therapy is supposed to help bring ideal hormonal levels back much faster, by accelerating testosterone production.

BUT: there can be OTHER side effects from using Aromatase Inhibitors This may especially be a problem for you if you take this stuff and you are not sure what you are stacking it with, or are not sure what you are doing. Problems include:  joint pains and stiffness, bouts of fatigue, and temporary lapses in memory or attention.

We have not heard of major problems with Animal Stak – but like we said, this product is usually recommended for veteran lifters. For this reason, we generally recommend you have 5+ years of focused experience with lifting and supplementation before using Stak .

  • Hormone Amplifying Blend:   L-Carnitine, Phosphatidylserine. These are the ingredients in Animal Stak’s Cortisol Inhibitor Complex. Cortisol causes the body to store abdominal fat, so these ingredients prevent that from happening.Again, L Carnitine alone is typically used in dosages of 1000+ mg . Stak is likely under dosed.
  • B-Sitosterol, Saw Palmetto Extract, Quercetin. These are DHT blockers. DHT is a hormone that’s a byproduct of testosterone. When you have too much of it, you may suffer from hair loss and your prostate may become enlarged. These ingredients keep the DHT from synthesizing, so you can prevent those problems.

Like we mentioned earlier, boosting performance and optimizing testosterone in the long run is not as simple as just blocking estrogen and DHT. Blocking too much DHT, or at the wrong times, actually reduces strength, immunity, and sexual function!

Gotta check for side effects.

So is Stak good for Post Cycle Therapy ?

Again, note that we are not advocating the use of “gear” or steroids – its just that there is an implied understanding that many pro bodybuilders and athletes are using.

Animal Stak helps to get your HPTA back online after a cycle.  (The Hypothalamic-Pituitary-Testicular Axis, or HPTA for short, is the thermostat for your body’s natural production of testosterone. Too much testosterone and the engine will shut off. Not enough, and the engine is turned up.)

It is an Aromatase Inhibitor (AI). It has a DHT blocker, which would come in very handy for an Epistane PCT (anabolic agent). And it has a cortisol blocker to help hang on to gains.

In contrast, A natural test booster is probably not a good idea for PCT. Most classic natural testosterone ingredients will affect HPTA and suppress you to some extent.

After a couple weeks your natural production of T will begin to come back online, then you can introduce an AI.There is no reason to go immediately to an AI the first week of PCT, so introducing Animal Stak in the second or third week would be a great way to finish the post cycle.

In the first week or two of your PCT there is no natural test production, therefore, no need for aromatization. During that first couple weeks of PCT you actually do not want to suppress whatever small amount of estrogen remains – your body needs it. You might use a SERM to block the negative effects of estrogen, but not block the production of it.

Proper PCT actually does 2 things: to raise Testosterone (HPTA) and to control unwanted estrogenic side effects. Balance is the key (Estrogen/Testosterone ratio) – and not just to block estrogen wholesale. You actually aim to control estrogen and to stimulate natural testosterone production.

Also: you should not use a natural test booster for post cycle therapy if you are on gear or juice. If you are taking powerful drugs you need to take real solutions for PCT to avoid as many side effects as possible. So Animal Stak might still need to be stacked with other PCT supplements, just to let you know.

Bodybuilders: Who Should Not Cycle?

  1.  You are younger than age 25:

Your natural testosterone is not likely to be low, and you are able to make good gains without gear. Also your hormones are still likely to be fluctuating, so cycling may very well mess up your endocrine system.

  1.  You are over 25 but have less than 5 years experience with focused workout plans and supplementation

If you have not been lifting hard naturally for at least 5 years, you have a lot of natural potential left. It is best to exhaust as much of your natural potential before resorting to gear. By using too soon, you may be short changing yourself. 

Why and How to Stack Animal Stak with other Universal formulas

Universal Nutrition designed Animal Stak to be used in a stack. That is, it should used with other supplements for optimum results.

Animal M Stak   

  • Used for hard gainers – Not exactly a testosterone booster
  • Meant to stack with Animal Stak
  • Very high caffeine dosage – close to 500g
  • Occasional complaints about pricing

You can use Animal Stak with M Stak (learn more on Amazon), which is designed to help you gain mass so that you can build muscle more effectively.

M-Stak uses two key ingredients Beta-Ecdysterone and Methoxyisoflavone; which are flavones. Flavones adapt or convert nutrients toward lean mass accumulation, a process known as nutrient partitioning- and anabolic flavones promote enhanced protein synthesis and nitrogen retention. These are the mechanisms most important for new muscle growth.

If you are bulking, all of the excess calories you are consuming will be properly utilized to make you anabolic – and not stored as fat. It also seems to make users truly hungry!

If your goal is to cut, M-Stak supposedly maximizes all the calories you consume and uses them to preserve lean mass gains. M stak also includes a “proprietary” stimulant blend that probably comes close to 500mg of caffeine! Something you should keep in mind.

FAQ: Animal Stak vs M Stak? As mentioned, this is not really a comparison as M stak is not meant to be a testosterone supplement. Stak is usually intended for older experienced users, and M stak is probably easier to use for most people. 

M Stak encourages your body to use the calories you consume into producing muscle instead of storing calories into body fat. It also helps in boosting your energy and enhancing your performance, so that you can lift heavier weights and last longer in the gym (click to see options on Amazon).

M Stak worked fairly well for us, but we hear occasional complaints about ineffectiveness from users, especially those who did not stack this well with other prohormone replacements and supplements. Also this has an overdose of stimulants in our opinion. So for most people, we recommend something else.

Animal Pak 

  • Not a test booster- gives you nutrients or multi vitamins
  • No need for cycling
  • Can be stacked with Animal Stak and M Stak

Another supplement that’s a popular complement to Animal Stak is Animal Pak (learn more on Amazon).

Which is better: Animal Stak vs Animal Pak?

Aimal Pak offers a foundation of nutrients you absolutely need in order to succeed in building muscles – more like a multi vitamin than a bulking supplement or test booster. Pak is pretty much useful for anyone – whereas Stak tends to be much more specialized. However, note that Pak is not meant as a “muscle builder” in itself.

  • If you are lacking key nutrients for bulking, Animal Pak offers ingredients that provide the necessary nutrients, and they also help in your recovery process. They cover the nutritional gaps you may have that may keep other supplements like Animal Stak from working effectively.For beginners: some supplements synergize or become much more effective when taken together, rather than when taken separately. Or, other stacks involve taking extra supplements that minimize the side effects caused by the other supplements.If you know what you are doing, combining Animal Stak with other supplements, or Universal Nutrition products, can bring great results. If not, you should probably try a test booster that is easy to use as solo as well in as a stack.

Animal Test Review:

Animal Test is a strong testosterone booster – however, it is also recommended for experienced lifters as the ingredients tend to be more complex as well.

Animal Stak vs Animal Test- what’s the difference?

Where Stak is mean to be used as a “balancer” for those who know how to use it (and ideally for PCT), Animal Test is meant to aggressively target testosterone levels alone (click here to see product on Amazon).

This still means Animal Test requires more planning to avoid other side effects in the long term- it is not likely you can use this without thinking over even just 2-3 months, without hormone fluctuations.

It’s ingredients such as Arachidonic Acid and Ketosterones are less documented in effects, but seem to work well. However, note that the use of Yohimbe is banned in many countries.

Animal Test Side effects: This product seems to create frequent cases of headaches and nausea, as well as acne. As noted above, this is likely seen in less experienced users.

Animal Test is known to be relatively expensive when used in the long term. Though not exactly a classfied “steroid”, this should probably be used as such as it is quite strong and targeted in its effects (in contrast with other supplements that act as testosterone support).

You probably need to use it in conjunction with other steroids (or legal replacements ) in careful cycles. In contrast, other supplements we use have more margin for error and are meant for regular use.