Is G Fuel Bad for You? The Truth About G Fuel Ingredients (Pre Workout Safe?)

Supplements & Vitamins | Written by Nathan Petitpas | Updated on 3 July 2024

A white G Fuel shaker cup filled with bright red liquid sits on a snowy surface, its vibrant contents creating a striking visual effect against the snow-covered background.

For people who are wondering about the safety of using G Fuel as a pre-workout, it is important to consider many factors before reaching a definitive conclusion.1

There are some ingredients in it that could be dangerous to consume in large quantities and has trace amounts of a questionable ingredient that must be disclosed due to California’s Proposition 65.

On the other hand, G Guel has a good combination of caffeine and well-researched ingredients which means it can be effective as a pre-workout when dosed intelligently.

Or in other words, it’s not exactly black and white and each person should at least consider the questionable ingredient and the dosages of vitamins, minerals and nootropics to decide if G Fuel is right for them.

Is G Fuel Good for You? Is G-Fuel Healthy?

When it comes to understanding whether G Fuel is healthy for an individual, there are a few things to consider.

To begin, G Fuel contains a decent amount of caffeine, around 150mg, which is more than the average energy drink. Caffeine is beneficial for a litany of reasons, but at the same time, too much can cause elevated blood pressure, headaches, dizziness, and even insomnia if drunk near bedtime.2

For those interested in effortless weight loss, G Fuel can act as both a non-nutritive energy drink and an appetite suppressant due to its caffeine content.

G Fuel also includes B vitamins and some electrolytes in G Fuel which all have positive health benefits. B vitamins, specifically, are key to ensuring that the body’s cells are functioning optimally, while electrolytes like sodium and potassium provide proper hydration, especially useful when working out.

This means that for people who are curious about the benefits of G Fuel for weight loss, it can be effective since it provides crucial vitamins and minerals for the body.

Overall, when G Fuel is used in moderation, it can increase focus, reinforce the body with vitamins and electrolytes, and can temporarily enhance energy from the caffeine content. However, if too many servings of G Fuel are consumed, it could potentially lead to negative side effects, discussed further down in this article.

Is G Fuel Harmful?

G Fuel does contain trace amounts of lead in it. So, for those wondering about the potential health effects of G Fuel, it can be unhealthy, but only in extremely high amounts.

The main thing to note here is that the lead inside of G Fuel comes from naturally-occurring sources. The amount of this lead is extremely low and is unlikely to cause health issues in the vast majority of consumers, but it’s still important to be aware of this and make sure not to over-consume G Fuel. Especially for a person who is pregnant or has prior health concerns, lead can be dangerous.

Regardless, G Fuel must disclose it has lead within the state of California thanks to Proposition 65, even though it has an extremely minute amount of lead in it.

All other ingredients in G Fuel are FDA-approved, so they are likely to be safe for a person to consume. But, keep in mind that some of the additives in G Fuel are not very well-researched, meaning that they could technically be dangerous since we do not definitively know if they are safe when consumed over a long span of time.

When Can G Fuel Be Harmful?

There are three main situations when G Fuel can be bad for an individual.

The first is when the person is overly sensitive to caffeine. A typical cup of coffee contains around 100mg of caffeine; with about 50% more caffeine in it than coffee, G Fuel can be overly stimulating for some. However, for other people who regularly drink coffee or drink a pre-workout already, they may not be affected; it is simply on a case-by-case basis.

The second is if a person has an intolerance to any of G Fuel’s additives. G Fuel contains both sucralose and acesulfame potassium, which affect people differently than natural sweeteners like stevia. If a person typically has an adverse reaction to these sweeteners, it may be a good idea to stray away from G FUEL.

On the artificial dye side of things, G Fuel contains a combination of Red 40 and Blue 1, for most flavors, with the former dye being linked to carcinogens and the latter potentially causing hypersensitivity.3 Similar to the warning about caffeine, this occurs on a case-by-case basis — try G Fuel out before determining if it is too risky to consume.

Finally, if a person is pregnant, has a history of heart problems, or has elevated blood pressure, then they should not drink G Fuel at all. This warning primarily comes because of the lead in G Fuel; while it is unlikely that a person will get lead poisoning, better safe than sorry.

Outside of these three situations, as long as a person is in decent shape and they do not over-consume G Fuel, it can be used effectively as, according to their website, a ‘vitamin-fortified energy complex’.

G Fuel’s Nutrient Profile (G Fuel’s Nutritional Information)

Now that we understand the potential risks of consuming G Fuel, let’s take a look at what vitamins and minerals are in G Fuel and their benefits or potential downsides.

G Fuel Macronutrients (Carbs, Fat, Protein) and Micronutrients (Vitamins, Minerals)

G Fuel contains no fat or protein and contains somewhere between 1-5 grams of carbohydrates per serving, tallying up to somewhere between 5 and 20 calories total.

This means that for manifesting weight loss, consuming G Fuel is great for beginners to cut out unnecessary calories from other sugary energy drinks. It is essentially non-caloric, and contains a litany of vitamins and other ingredients that can help provide lasting focus and strength throughout the duration of a workout.

A graphic illustration of two bottle of vitamins such as Vitamin C in an orange color and Vitamin B12 in a yellow tablet form.

Source: Clker-Free-Vector-Images on Pixabay4

B vitamins are crucial for maintaining proper cellular function, while electrolytes help to hydrate the body and keep it performing optimally when working out.

G Fuel also contains Vitamin C as ascorbic acid, Vitamin E, and choline, which is typically used as part of a Vitamin B complex. In tandem, these vitamins help to provide a good nutritional base for people who don’t normally consume these vitamins via food or supplement.

As part of any trending diets, G Fuel can certainly be a beneficial supplement.

One other thing to note on the nutritional side of things is that G Fuel contains zero grams of sugar – Gamma Labs, the producer of G Fuel, prides itself on only using artificial sweeteners. This is both a good and a bad thing, but that will be discussed further along in this article.

G-Fuel Caffeine Amount

G Fuel contains somewhere between 140 and 150mg of caffeine per serving, depending on the flavor. This is higher than a cup of coffee, which typically has somewhere between 80 and 130 mg of caffeine per 8 oz cup.

A silver cup of coffee beans on top of a large pile of more coffee beans.

Source: Foundry on Pixabay5

The FDA says that healthy adults can safely consume up to 400mg of caffeine per day, but keep in mind that multiple servings of G Fuel pushes close to this limit.

It should also be noted that G Fuel contains more caffeine than Monster Energy or Red Bull, both of which contain nearly 90mg of caffeine per serving.

Keep in mind, compared to most pre-workouts, one serving of G Fuel is nothing, with many totaling up to more than 300mg of caffeine per serving. But, out of common energy drinks, it still has more than many others on the market.

For those wondering about ways to distract themselves from hunger, the caffeine in G Fuel actually makes it a viable option. Most people love caffeine for the stimulating effects it provides, but what many people don’t know is that it also acts as a strong appetite suppressant.6

This doesn’t necessarily mean that people should drink as much caffeine as possible to suppress their appetite – that can only lead to long-term issues. But, appetite suppression will be a side effect of drinking large amounts of caffeine, like that in G Fuel.

Ingredients In G Fuel & Their Implications on Your Health

Moving along from the main nutritional facts of G Fuel, it is time to get to the bulk of this article – discussing the various other ingredients included in G Fuel These ingredients do not contain calories, but they do have a substantial effect on what G Fuel does for a person, mentally and physically.


Taurine is the first ingredient listed in G Fuel and is an amino acid that has been linked to a variety of positive health benefits. Some of these include things like improved heart health and blood pressure, reduced muscle fatigue and cramping, and can even provide some level of antioxidant protection.

However, the amount of taurine in G Fuel is unknown — it is included as part of their Energy Complex which does not directly label how much of each ingredient is included.

That being said, while it is difficult to determine how much taurine is included, it seems that any amount of taurine supplementation can be beneficial in minimizing the severity of inflammatory diseases like heart failure, atherosclerosis, and hypertension.7 Taurine is also likely to help improve skeletal and cardiac muscular dysfunction, and can even be used to assist in recovering from congestive heart failure.

Taurine is the most researched supplement included in G Fuel, and considering the litany of health benefits it has, it is included in the vast majority of energy drinks, so it’s not surprising to see it here.


L-Tyrosine is an amino acid that is used by the body to produce dopamine and norepinephrine, two hormones that are associated with alertness, focus, and concentration.

Similar to taurine, the L-Tyrosine included in G Fuel is in an unknown amount — it exists as part of the Focus Complex. But, L-Tyrosine in general can contribute to long-term mood benefits, so for those wondering “whether G Fuel is bad for you,” the L-Tyrosine in it can contribute to an overall better mood, and L-Tyrosine weight loss is also common, making G Fuel have more than just cognitive benefits.

One last thing to note is that L-Tyrosine seems to be a slightly more effective version of N-Acetyl-L-Tyrosine. The latter is meant to be a more bioavailable version of the former, but most people tend to feel more benefits from L-Tyrosine itself, so it is good that G Fuel includes it.

L-Citrulline Malate

Different from L-Tyrosine since it is a non-essential amino acid, L-Citrulline Malate helps to reduce fatigue and improve muscle endurance.

It also seems to help improve blood flow and even reduce blood pressure, which is the main reason it is used to treat health problems like sickle cell disease, high blood pressure, and erectile dysfunction.8

L-Citrulline Malate is included as part of the Energy Complex, meaning we don’t know how much is actually in a serving of G Fuel.


Produced naturally by the body, Glucuronolactone supplementation seems to assist with mental alertness and is meant to detoxify the body by binding to toxins in the liver.

That being said, the main information that exists on the internet about Glucuronolactone is that the evidence on what it does is inconclusive at best.

An outdoor photo of a can of red bull energy drink.

Source: Alexas_Fotos on Pixabay9

In one paper, the Red Bull Company claims that Glucuronolactone is involved in detoxifying the body – but there hasn’t actually been a study done to verify this claim.10 Further, it is noted that when confronted about their claim, the Red Bull Company was unable to cite a source for their claim and was not even aware of the effects of Glucuronolactone.

Like L-Citrulline Malate, the Glucuronolactone inside G Fuel is labeled as part of the Energy Complex, meaning it is impossible to know how much is actually inside a serving of G Fuel.

Keeping that in mind, it is unlikely it can have bad effects on the body in small amounts considering it is endogenously made by the body. But, the purported benefits may not even exist.

N-Acetyl-L-Carnitine HCl

N-Acetyl-L-Carnitine has been linked to improved physical performance and enhanced focus, making it an ideal ingredient for a “gamer” fuel.

As a supplement, Acetyl-L-Carnitine is used to help improve memory and thinking skills, treat depression, and even minimize chances of developing Alzheimer’s disease.

The core thing to note here is that there is not too much research done on N-ALC HCl. The closest research to it was done on Acetyl-L-Carnitine supplementation – a meta-analysis of multiple studies concluded that ALC has the potential to improve mental function and minimize deterioration in those with Alzheimer’s disease.11

However, keep in mind that subjects in this study took 1.5-3 grams of ALC per day for 3-12 months, while G Fuel contains likely less than 1.5 grams due to it being part of the Energy Complex. This means that the amount of N-ALC HCl in G Fuel may not even be enough to offer any of these cognitive benefits.


Similar to L-Tyrosine, but more easily absorbed by the body, N-Acetyl-L-Tyrosine may provide a longer-lasting mental boost than regular L-Tyrosine, potentially alleviating long-term depressive symptoms, although there is only anecdotal evidence online to suggest that.

It is included in the Focus Complex, along with L-Tyrosine, and has similar effects – but, as aforementioned, it likely exists within the body slightly differently and offers long-term mood benefits when compared to standard L-Tyrosine.

Adenosine-5 Triphosphate Disodium Salt (ATP)

Adenosine-5 Triphosphate is a compound that helps the body to produce energy, which should subsequently help people who consume it to have higher stamina.

The main thing to note here is that research on ATP 5 Disodium Salt is inconclusive at best. While one study concludes that orally consuming it does not have the effect of increasing ATP levels, another study argues that ATP supplementation may help muscular adaptation in tandem with resistance training.12, 13

That being said, it is unlikely to be a dangerous part of G Fuel’s Focus Complex.

Antioxidant Complex (Mixture of Powdered Fruits)

This is a blend of powdered fruits that helps to reduce free radicals and protect the body from oxidative stress. In general, antioxidants help to protect the body from diseases like cancer, diabetes, and heart disease by eliminating free radicals.

The complex in G Fuel includes dried fruit powders from fruits like Acai, Pomegranate, Blueberry, Pineapple, Cherry, Strawberry, and a few other fruits, but these are the main ones that are typically purported to be the best for the body.


Typically added to powdered products to minimize the calorie count while increasing the amount of product there is, Maltodextrin is a filler with a low glycemic index (does not spike blood sugar much) and is easy to digest in most cases.

Most people digest maltodextrin easily, but in one study, researchers concluded that it has similar harmful effects on the body to sucrose even though maltodextrin is non-caloric.14 It was seen to increase weight gain parallel to sucrose weight gain and similarly impaired performance on a location recognition task.

That being said, in small amounts, it is unlikely for maltodextrin to be extremely harmful, but over-consumption could be bad for the body.

Citric and Malic Acid

Citric Acid is an organic acid that helps to preserve and add flavor to products. It is one of the main components of lemon juice, which doesn’t automatically make it the safest ingredient ever, but because it is naturally occurring in other fruits, and has not been shown to have negative effects, it is likely safe to consume.

Similar to citric acid, research on Malic Acid is minimal, but it seems like it helps the body to absorb iron. It is organically found in wines and certain fruits, similar to citric acid, so it is unlikely to have negative effects on those consuming it; otherwise, there would likely be a widespread outcry about the dangers of eating certain fruits that contain Malic Acid.

Silicon Dioxide

A natural mineral, Silicon Dioxide helps prevent powders from clumping together, improving the overall texture. It is commonly found in powdered foods or drink mixes like G Fuel.

Including silicone in a drink mix might seem strange since we often associate it with being harmful to consume, but it’s important to note that silicon and silicone are two different materials; silicon is natural, while silicone is manmade.

Luckily, studies show that there is no correlation between silicon dioxide and things like reproductive health, body weight, or birth weight, which suggests that it is unlikely to have negative effects elsewhere.

Does G-Fuel Have Artificial Sweeteners? Does G Fuel Contain Acesulfame Potassium or Sucralose?

Yes, G Fuel contains two artificial sweeteners, Acesulfame Potassium (Ace-K) and Sucralose. These are both calorie-free sweeteners that help to provide a sweet taste without including the calories that standard sugar provides.

The only caveat to keep in mind here is that for those who are aiming to stay on a keto diet. Both Ace-K and Sucralose are low in carbohydrates, but they can still affect a person who is in ketosis since they can spike blood glucose levels. Compared to standard caloric sugars, though, these artificial sweeteners have a significantly lesser impact on overall blood glucose, so this warning should only be heeded by those who are extremely sensitive to sweeteners.

Additionally, for those who may be sensitive or have adverse reactions to these sweeteners, it would be wise to steer clear of G Fuel. This advice also applies to those curious about the health impacts of Mio, the keto compatibility of Propel, or the effectiveness of Bang for weight loss. These drinks are generally fine for avoiding blood sugar spikes, but some people might have adverse reactions to excessive artificial sweeteners.

Is G-Fuel Good for Working Out? Is G-Fuel a Good Pre-Workout?

G Fuel can be an effective pre-workout supplement because it has a mixture of well-researched ingredients that work in tandem to provide a high level of energy, focus, and vitamins to support the body’s underlying mechanisms.

G Fuel contains two different groups of ingredients that Gamma Labs calls ‘Complexes”.

The Energy Complex includes:

  • Taurine
  • L-Citrulline Malate
  • Caffeine
  • Glucuronolactone
  • N-Acetyl-L-Carnitine HCl

And the Focus Complex contains:

  • L-Tyrosine
  • Choline Bitartrate
  • N-Acetyl-L-Tyrosine
  • ATP Disodium Salt

Combining these two complexes into one sports drink makes it beneficial both for physical activities, like weightlifting, as well as cognitive activities like gaming.

Actual pre-workouts typically include larger amounts of caffeine, creatine, beta-alanine, and L-arginine, with the latter three ingredients proven to be extremely beneficial for long-term muscle growth.

Since G Fuel is not branded as a pre-workout, and is meant to act more as a focus enhancer for gamers, it does not contain creatine, beta-alanine, or L-arginine, meaning it is likely less effective than standard pre-workouts. That being said, G FUEL contains more vitamins than typical pre-workouts, making it better for overall nutrition.

One caveat about consuming G Fuel is that for those who are sensitive to caffeine, the level of caffeine included per serving could be a bit of a shock to the body. This can potentially make a workout more difficult due to increased heart rate, and blood pressure, and potentially even lead to dehydration mid-workout.

For those who are already in decent shape, do not have many health concerns, or already consume caffeine in sizable quantities, G Fuel can be effectively used as a pre-workout supplement (even if it wasn’t originally intended to be one).

How Much G-Fuel Can You Drink in a Day?

G Fuel recommends on their website to start with one serving of G Fuel to see how it affects the individual. Meaning, a serving of 150mg of caffeine; a can of G Fuel, on the other hand, contains 2 servings of G Fuel, so one can has 300mg of caffeine.

They recommend on their website to not consume any more than this, mainly for the large amount of caffeine that a person would have in their body at once if they consumed more than this.

But, anecdotally, there are thousands of people who drink immense amounts of caffeine frequently; simply Google “caffeine before workout Reddit” to see what different people drink. Some people report drinking 750mg of caffeine before a workout to get a good effect, while others recommend not doing it at all.

The variation in what is preferred should emphasize that this is a subjective action; if a person progressively drinks more and more caffeine over time, then drinking a can or two of G Fuel at once may not affect them that much. But if they jump from 0mg of caffeine to consuming 300mg within the span of a few minutes, negative effects will likely follow.

G-Fuel Side Effects: What Are Common G-Fuel Side Effects?

G Fuel has a variety of side effects depending on how sensitive an individual is to specific ingredients like dyes, artificial sweeteners, or caffeine. More often than not, side effects are not very severe and include:

  • Nausea
  • Headaches
  • Jitters
  • Anxiety
  • Restlessness
  • Insomnia

The above side effects would likely be caused in those who are sensitive to caffeine since too much caffeine can raise blood pressure and lead to things like headaches, anxiety, and insomnia.

To tie it back to an above point, this applies to people who jump from drinking a small amount of caffeine to a large amount very quickly; so, switching from a cup of coffee to a can of G Fuel before a workout may cause some of these effects.

The other ingredients included in G Fuel’s complexes have not been shown to have negative effects.

However, as aforementioned in this article, those who are pregnant, breastfeeding, or have any other medical conditions should not consume G Fuel without discussing it with their doctor first. That being said, the vast majority of people that consume G Fuel will have few, if any, side effects.

Talking with a doctor is simply a wise precaution to take for those people who may be predisposed to poor health conditions.

G Fuel is generally safe for most people when consumed in moderation, such as at a slower pace and limited to no more than 2 servings per day.

Does G Fuel Have Lead? How Much Lead Does G Fuel Have?

As aforementioned, G Fuel does contain some lead in it. Based on our research, this amount is not listed on any labeling because it does not contain enough lead to amount to dangerous levels of it in the blood.

According to the FDA, this recommended threshold is 3.5 micrograms/dL – their current recommendation is to consume less than 2.2 micrograms per day for children and less than 8.8 micrograms per day for women of childbearing age to avoid this threshold so we’d assume G Fuel has less than 3.5 micrograms/dL.

However, it is important to note that lead can accumulate in the body if consumed without detoxing or allowing the body to rid itself of lead, so consuming G Fuel consistently over a long period of time could lead to some negative effects.

Is G-Fuel Safe? Is It FDA Approved?

When consumed in moderation relative to the individual’s caffeine tolerance, G Fuel is safe to drink. It is important to note that G Fuel is not FDA-approved, but that is only because it is a supplement.

The FDA only approves things classified as drugs, whereas G Fuel is considered a sports supplement.

Regardless, if an individual is concerned if they are healthy enough to drink G Fuel, they should discuss with their doctor the various ingredients in G Fuel, or even just watch a comprehensive YouTube video about it. Without proper awareness of what is actually inside it, it can be dangerous to drink.

But, to directly answer the question “is G Fuel harmful to your health,” no, it is not, but for those who plan on drinking it regularly, they need to be aware of the potential risks that can arise from drinking too much of it.

Frequently Asked Questions

Is G Fuel an Energy Drink?

Yes, G Fuel is technically considered an energy drink. However, it does not contain large amounts of sugar like other common energy drinks on the market, so it stands apart from its competitors in that right.

Who Makes G-Fuel?

G Fuel is made by Gamma Labs, a dietary supplement company based in the United States. They have been in business since 2004 and specialize in making healthy and natural energy drinks.

What Is G Fuel Good For?

G Fuel is primarily designed to give energy and focus, while also providing a variety of antioxidant benefits.

Additionally, it can help reduce fatigue and improve mental clarity. It can also help boost physical performance and endurance levels, making it useful for those who are active or exercise regularly.

Does G-Fuel Have Sugar?

G Fuel does not contain any sugar, so it is safe for diabetics and those watching their sugar intake. But, it does contain some artificial sweeteners, so for those who want to limit their blood glucose levels, G Fuel may not be the best.


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About the Author

Nathan Petitpas

Nathan has been a fitness enthusiast for the past 12 years and jumps between several types of training such as bodybuilding, powerlifting, cycling, gymnastics, and backcountry hiking. Due to the varying caloric needs of numerous sports, he has cycled between all types of diets and currently eats a whole food diet. In addition, Nathan lives with several injuries such as hip impingement, spondylolisthesis, and scoliosis, so he underwent self-rehabilitation and no longer lives with debilitating pain.