GNC is a well-known vitamin and supplement retailer. For those unfamiliar, entering a GNC store can be daunting. The shelves are filled with pill bottles, dark canisters, and often very muscular individuals. Navigating the store’s website might be simpler—or more complex—depending on your shopping style. You can browse by goals, but each goal presents numerous options that can be difficult to narrow down. Since the FDA regulates supplements differently from drugs, safe and transparent ingredient labels are rare, even when ingredients are listed (via American Cancer Society).
A 2015 study published in the New England Journal of Medicine found that an average of 23,000 emergency room visits each year are due to adverse reactions to supplements. The study emphasized that not all supplements are safe. Yes, even those available at GNC may not truly be beneficial for you. Let’s explore some of these products.
Nugenix Maxx
Nugenix and other testosterone boosters are favored by men who enjoy gym workouts. Testosterone and other hormone replacement therapies can be highly effective when supervised by a doctor, as explained by WebMD. However, when over-the-counter supplements appear, experts advise caution before using them. This is because many over-the-counter testosterone supplements have little to no evidence supporting their claims (via WebMD).
Synthetic versions of testosterone exist, and while they are beneficial when prescribed by a doctor, they are often abused. This abuse can lead to long-term health issues. Without obtaining a legal drug, you can buy a testosterone booster like Nugenix Maxx at GNC. These supplements are marketed as “testosterone boosters” and contain a vitamin mix with scant evidence proving their effectiveness.
According to Science Daily, many ingredients and vitamins in these boosters are present in higher volumes than are safe to consume. Additionally, less than 25% of the supplements studied could actually boost testosterone levels. While this may not be the absolute worst product sold at GNC, it is an expensive waste of money.
L-glutamine supplements
As of this writing, GNC sells over a dozen L-glutamine supplements online. While L-glutamine is not exactly harmful, it seems to be one of the less useful supplements sold at GNC. Glutamine is one of the 20 amino acids, and it is the only one with two molecular forms, L-glutamine and D-Glutamine. L-glutamine is one of the non-essential amino acids, meaning it is naturally produced in the body (via WebMD). In fact, L-glutamine is one of the most abundant amino acids produced within our muscles.
Although glutamine can be useful for certain people – like those with HIV, AIDS, or IBS – there is no evidence to support that supplementing this amino acid can enhance athletic performance, even though it is often marketed that way. In fact, overusing L-glutamine can result in nausea, vomiting, joint pain, and hives (per Healthline). Additionally, Healthline reported that some cancers “increase rapidly in response to L-glutamine.” The article continued, “For this reason, it may be advised for those with cancer, or with high risk of cancer, to avoid supplements.”
Herbal Plus Cayenne Pepper
Capsaicin is a compound naturally found in cayenne peppers and other spicy peppers. Capsaicin is the source of the burning sensation you feel after eating a spicy pepper. This specific spicy element has been shown to be an appetite suppressant. Ongoing studies are proving that capsaicin has anti-inflammatory properties. Experts recommend consuming it in raw form, although eating peppers instead of supplementing can also provide you with ultra-healthy antioxidants (via Healthline).
The Herbal Plus Cayenne Pepper capsules are one of the more affordable supplements available at GNC. This is great, but not when compared to buying an actual cayenne pepper, which is available for less than a dollar in grocery stores. Moreover, ingesting too much capsaicin can lead to gastrointestinal distress.
One of the main side effects of supplementing capsaicin is a burning sensation along the entire length of your GI tract, from mouth to exit (per Healthline). The benefits of capsaicin can best be reaped by incorporating spicy peppers into your diet, no pill form necessary, explained WebMD.
Total Lean Chitosan With Glucomannan
Chitosan with glucomannan is quite a tongue-twister. The logic behind this supplement’s popularity is a bit of a brain-twister too. Chitosan is derived from the exoskeletons of crustaceans, including shrimp, lobsters, and clams, as outlined by WebMD. Chitosan is marketed as a wonder drug that can reduce the amount of fat absorbed in the intestinal tract.
According to the GNC website, the Total Lean brand of chitosan is said to “help promote a feeling of fullness,” likely due to the psyllium husk included in the formula. Psyllium husk is a naturally occurring compound proven to aid in weight loss (via Medical News Today).
Chitosan does not occur naturally in foods, as it is extracted from the hard shells of sea creatures and some insects. No dosage standards have been set, and the quality and quantity vary in each formulation, WebMD explained. Chitosan is generally only unsafe for people with shellfish allergies and those who take blood thinners. But since none of the weight-loss benefits have yet been proven, this is another supplement not worth the expenditure. Experts at WebMD encourage consumers to talk to their doctors to avoid any potentially harmful drug interactions.
Sports Research Garcinia Cambogia
Products formulated with garcinia cambogia, such as Sports Research Garcinia Cambogia, are marketed as a stimulant-free method to gain more energy and burn fat by merely existing. Garcinia cambogia is a compound found in the rind of Malabar tamarind, a tropical fruit. The active ingredient is hydroxy citric acid, which scientists believe can raise serotonin levels and decrease hunger sensations (via WebMD).
However, there is a dark side to this seemingly harmless tropical fruit. In 2017, the FDA released a statement declaring that garcinia cambogia is unsafe and linked to serious liver problems (WebMD). Additionally, garcinia cambogia has the potential to interact poorly with popular painkillers, diabetes medications, and psychiatric drugs.
Though this naturally occurring chemical compound can act as an appetite suppressant, the weight loss results are not promising. Experts recommend skipping the magic bullet and hiring a personal trainer instead.
Cellucor C4 Ultimate and BSN N.O. -XPlode pre-workouts
Pre-workouts are extremely popular, which is unsurprising since they essentially consist of large amounts of habit-forming caffeine. The most popular varieties sold at GNC include Cellucor C4 Ultimate Pre-Workout and BSN N.O. -XPlode, which contain 300 milligrams and 275 milligrams per scoop, respectively.
Pre-workouts can be harmful due to the sheer amount of caffeine they contain (via Fox 25). An average 8-ounce cup of coffee contains around 95 milligrams of caffeine, though the type of beans and roast may affect the actual amount (per Healthline). Consuming coffee in the morning and then a pre-workout before the gym can potentially lead to excessive caffeine intake. The side effects of overconsumption are unpleasant but not usually life-threatening and include extreme jitters, nausea, vomiting, cramps, and high blood pressure. In very rare cases, pre-workout has caused cardiac arrest (via Fox 25).
Even GNC cautions that the Cellucor pre-workout it sells is “only intended for healthy adults, 18 years of age or older” and advises purchasers to “consult a licensed, qualified, healthcare professional” before using it. When used in moderation, pre-workout can assist in achieving a good pump. But with all the extra, unregulated ingredients involved, the experts at Healthline urge you to caffeinate with caution.
Beyond Raw Chemistry Labs L-Carnitine
Not to be confused with the legitimate amino acid L-glutamate, L-carnitine is an amino acid-like substance. It is similar to a chemical compound produced in the human body, as explained by WebMD. L-carnitine has been FDA-approved to treat kidney and other diseases. However, its effectiveness as a fitness supplement has been underwhelming at best, as research has shown.
The GNC website states that the Beyond Raw Chemistry Labs brand of L-carnitine “facilitates the metabolism of long-chain fatty acids and helps transport them in your body.” But a study published in the International Journal of Sport Nutrition and Exercise Metabolism noted that L-carnitine supplementation has no effect on substrate utilization or athletic performance.
In case you’re not exercise physiology enthusiasts like us, “substrate utilization” can be loosely explained: During slow, steady-state workouts, the main energy source (substrate) is fat. Conversely, during high-intensity work, carbohydrates are the primary fuel source. Ultimately, L-carnitine isn’t harmful, but it’s yet another supplement sold at GNC that isn’t worth your money.
Bpi Health Keto Weight Loss
It would be negligent to overlook the glaring red flag within GNC’s Bpi Health Keto Weight Loss product description. It clearly states that “electrolytes … may be depleted during a ketogenic diet.”
If you’re unfamiliar with the latest fad diet, let us introduce you to the ketogenic diet. The concept is to severely limit carbohydrates. If you don’t provide your cells with their preferred fuel source, carbs, your body will switch to using its second favorite fuel source, fat. If you maintain this state long enough, your body will become efficient at this, which is called “ketosis” (via Healthline).
The keto diet is effective for weight loss, though it is not considered sustainable. And what about the supplements? They may work to some extent, but as Barbara Gower, a professor of nutrition sciences at the University of Alabama at Birmingham, told Insider, “The results of studies on keto supplements are inconsistent, and marginal at best,” says Gower. They’re also pretty unnecessary. Ariana Fiorita, a registered dietitian at the Center for Functional Medicine at Cleveland Clinic, told Insider, “Keto pills and drinks can be costly and often contain all the ingredients you already have at home.”
Trace Minerals Colloidal Silver
The product description for Trace Minerals Colloidal Silver on GNC’s website advises consumers to use it “until desired results are attained.” So what, we wonder, could these desired results be?
The National for Complementary and Integrative Health describes colloidal silver as tiny silver particles in a liquid, sometimes promoted as a dietary supplement. Colloidal silver is often marketed as a magic-bullet type substance. Manufacturers often claim it can prevent infections, treat congestion, and boost your immune system. It has also been rumored that colloidal silver can aid in treating HIV and AIDS, cancer, herpes, shingles, and eye problems. Yet, no research exists to support these claims, confirmed WebMD.
In fact, consuming colloidal silver can be downright dangerous. The FDA has been warning against the effects of colloidal silver since 1999. The most common side effect is argyria, which is the bluish-grey discoloration of the skin, according to the National Center for Complementary and Integrative Health. Colloidal silver can also interfere with many medications, making it a danger to many. As it is not an essential mineral and could, in fact, be harmful, you should consider avoiding colloidal silver altogether.
Jarrow Formulas Wild Bitter Melon Extract
GNC’s marketing of Jarrow Formulas Wild Bitter Melon Extract may give you pause. The product description reads: “Supports blood pressure and blood sugar already in the normal range.” So, if it’s already in the normal range, one might argue a supplement isn’t needed.
Bitter melon appears fresh and wonderful, but just like our girl Britney, bitter melon is not that innocent. Most research on bitter melon has been inconclusive. Many researchers believe it may help your cells use and move glucose. However, many researchers agree that more tests should be conducted before further claims are made (via Healthline).
Bitter melon’s side effects are quite aggressive and worth noting. According to Healthline, side effects can include nausea, vomiting, diarrhea, anemia, liver damage, contractions, vaginal bleeding, and even abortions. With such high stakes for side effects, we don’t think we’ll be heading to GNC to buy bitter melon extract anytime soon.
Goli Nutrition Apple Cider Vinegar Gummies
TBH, there’s nothing truly unhealthy about Goli Nutrition Apple Cider Vinegar Gummies. But there’s nothing especially healthy about them either (via Bustle). Apple cider vinegar is widely regarded as a safe and healthy product to ingest. Researchers have proven that munching ACV gummies won’t harm your health, but they’re unsure if chomping is as effective as swigging (per Bustle).
Goli gummies contain 500 milligrams of apple cider vinegar, made up of 5% acetic acid. Acetic acid is the common component of most vinegar and is thought to be the cause of the health benefits, explained Bustle. However, these gummies sold by GNC include cane sugar, as well as many additives common in gummy candy. Since experts are unsure about the effects of ACV in gummy form and each one contains 4 unnecessary grams of carbohydrates, we’ll pass. We prefer our gummy bears without the salt-and-vinegar chip vibe, anyway.
MuscleTech Hydroxycut Hardcore Elite
While Hydroxycut may be popular, and yes, we might have even tried it in the past, it is problematic on several levels and should really be avoided at all costs. The two main ingredients that experts take issue with are green coffee extract and Yohimbe extract.
WebMD states that Yohimbe, which goes by various names, can cause increased blood pressure, rapid heart rates, headaches, liver and kidney issues, seizures, panic attacks, heart problems, and death. While it might not seem like much, the 56.3 milligrams per serving in MuscleTech Hydroxycut Hardcore Elite is a lot of any substance that lists death as a very possible side effect.
While green coffee extract is widely used as a stimulant, Medline Plus revealed that there is insufficient evidence to prove that it reduces the symptoms of many diseases. Green coffee extract is sourced from unroasted coffee beans and is said to have weight loss properties. The same study contains an incredibly long list of medications that green coffee extract may interact with. This seems like reason enough to take our coffee beans roasted and combined with milk in the form of our daily latte.
