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You may have heard of PhenQ, the fat-burning supplement created to help you improve metabolic health and suppress your appetite. Maybe you haven't tried it because you haven't seen good results with other weight loss supplements, or the PhenQ reviews you've seen online seemed like sensationalized "magic diet pill" or "diet pill scam" clickbait. What you could use is some honest information from someone who's tried PhenQ weight loss pills.
I tested PhenQ for a full 30 days to see how effective it is. This PhenQ review will cover my experience and results and help you make an informed decision.
As you read this review—or any PhenQ reviews—it's important to keep a couple of things in mind. First, an effective weight management plan has to include diet, exercise, and regular sleep. Using a fat burner or appetite suppressant alone will not produce significant or lasting results. Second, even the makers of the PhenQ weight loss supplement acknowledge individual results may vary. In my case, I've been active in fitness for more than two decades as a personal trainer, fitness class coach, supplement advisor, and more. My results may or may not be typical, but I have the expertise to provide you with a knowledgeable and comprehensive PhenQ review.
This content is meant to be informative, but should not be taken as medical advice. It is not intended for use as diagnosis, prevention or treatment of health problems. Always speak with your doctor before starting any new supplement or exercise regimen.
If you have a history of eating disorders, disordered eating, or any underlying health conditions it is important to discuss your weight loss goals with a doctor first. Always consult with a medical professional before starting a new diet, exercise routine, and/or weight loss program to ensure it’s right for you.
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PhenQ is an over-the-counter weight loss supplement formulated to target key areas of metabolic health with the goal of decreasing excess body fat, reducing cravings, and supporting natural energy production. The company says PhenQ weight loss pills use a science-backed formula, citing research involving key ingredients α-Lacys Reset, Capsimax powder, and chromium picolinate. PhenQ recently updated its formula to include iodine, B vitamins, and InnoSlim (a blend of the herbs ginseng and astragalus).
It doesn't appear PhenQ is third-party tested for efficacy and quality by an independent laboratory. The website currently does not mention third-party testing, but we have reached out to the company for clarification.
I tried PhenQ from May 26, 2023 to June 24, 2023, one pill around 8 a.m. for breakfast and one pill around noon for lunch. (For full disclosure, I missed two afternoon servings during this 30-day period.)
After the 30 days were up, I saw these results:
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Before trying PhenQ, I had already been using other supplements, including a non-stimulant vasodilator, whey isolate protein powder, a joint formula, and a melatonin supplement. I have continued to take those throughout this period. I also had been eating 250 grams of protein, 250 grams of carbs, and 50 grams of fats divided up over five meals, as well as drinking a gallon of water a day. I allowed myself two meals a week to eat whatever I wanted, but most of my meals were made up of whole food sources with little to no processed foods. I would sleep anywhere from six to seven hours a night.
As for my training, I do a 20-minute walk every morning before breakfast and train with weights five days a week in the afternoon, followed by a 15–20 minute high-intensity interval training (HIIT) workout. I did my best to minimize any other changes so I could get the most accurate differences with PhenQ and report how effective it truly was.
I'd like to share a little background on myself before going into my experience so you have a better understanding. I've been active in fitness for 25 years and have worked in the fitness industry in a variety of roles since 2002. As a fitness writer and product reviewer, I've had the opportunity to test many supplements on the market.
The opportunity to try PhenQ came at a great time since I was focusing on losing weight and preparing for my 5K. Before this review, I wasn't familiar with PhenQ before this review, and I have no direct connections to the company that produces it.
With all the background and disclosures out of the way, here are the main takeaways from my PhenQ experience:
Based on my personal experience and knowledge of how PhenQ works, I feel people who are looking to lose weight, get in better shape, and/or improve focus and performance would benefit from taking PhenQ. I certainly did and am glad to have had the opportunity. People from all fitness levels ranging from beginner to advanced could potentially improve their personal fitness success with this product.
When it comes to products like PhenQ, real reviews (like this one) do more than regurgitate the company's marketing pitch. To further explain and evaluate the benefits PhenQ claims it can bring, we turned to Pete Nastasi, certified weight loss practitioner and sports nutrition expert.
"The primary fat-burning ingredients in PhenQ are α-Lacys Reset and Capsimax powder. Both provide the user with an intense thermogenic effect that helps to boost metabolic rate and stimulate the fat burning process," says Nastasi. "Thermogenesis is the conversion of an energy source into heat. In this case, the energy source is body fat in the form of brown adipose tissue (the type of fat that regulates your body temperature). These ingredients help mobilize excess fat and prioritize it as the main energy source for the body instead of carbohydrates."
"PhenQ states the Capsimax powder in the formula may help to inhibit the body's ability to store fat cells and even stop new fat cells from growing altogether," says Nastasi. "This would theoretically help prevent additional weight gain when using the supplement, and is the reason some consumers decide to continue using the product even after they achieve their weight loss goals. PhenQ notes this effect is accomplished without drastically changing one's current dietary habits."
"A caloric deficit is an essential component of the weight loss process," says Nastasi. "However, this deficit often results in an increased appetite and intense cravings for calorically dense foods. The combination of caffeine, chromium picolinate, and nopal cactus in PhenQ are included to reduce these cravings, balance blood sugar levels, and suppress the appetite through an increased feeling of fullness."
"Sticking to a strict weight loss regimen is more difficult when cutting calories leads to feelings of fatigue. This is especially true when dieters follow a weight loss program that limits carbs," says Nastasi. "This fatigue not only affects your mental health but can also decrease the likelihood of going to the gym and exercising. PhenQ aims to resolve this issue through its blend of natural caffeine and Capsimax powder. These ingredients work together to burn extra body fat in order to naturally boost energy levels."
"PhenQ includes the naturally occurring amino acid L-carnitine to provide cognitive support for those who struggle with daily mental fatigue," says Nastasi. "PhenQ states this ingredient will help to keep you feeling motivated and positive while shedding excess weight."
Nastasi also shared his expertise in analyzing the ingredients of PhenQ diet pills—what they are, what they do, and how they fit into the overall formula.
The ingredient α-Lacys Reset is a trademarked, proprietary formula labeled as a combination of alpha-lipoic acid, L-cysteine, and magnesium. Here's a breakdown of those three components:
According to Nastasi, studies involving alpha-lipoic acid and L-cysteine have shown promising results in weight loss and appetite suppression, respectively.
"In two studies, alpha-lipoic acid supplementation resulted in statistically significant weight loss at dosages of 600 and 1,200 milligrams per day," he says. "L-cysteine has been shown to reduce perceptions of hunger and decrease the amount of the hunger hormone ghrelin in the body. This study used a dosage of 0.07 grams per kilogram of body weight for the individual participants."
For reference, says Nastasi, a 150-pound person would need to consume approximately 4,700 milligrams of L-cysteine per day to have the desired effect.
Despite the study findings, Nastasi points out PhenQ contains a total dose of only 25 milligrams of α-Lacys Reset per pill.
"Even when consuming two pills, resulting in 50 milligrams of α-Lacys Reset per day, this ingredient is underdosed for both alpha-lipoic acid and L-cysteine," he says. "At this dosage, it's unlikely this ingredient will demonstrate any reported weight loss benefits."
The Capsimax powder used in PhenQ diet pills is a blend of 34.5 milligrams of caffeine anhydrous, 8 milligrams of capsicum fruit extract, 4.5 milligrams of niacin (Vitamin B3) and 3 milligrams of black pepper fruit extract (piperine).
"The main active ingredient in Capsimax is the capsaicinoids inside of the capsicum fruit extract, which help suppress calorie intake through appetite suppression," says Nastasi. "This compound is also known for lipolysis (breakdown of fat stores), thermogenesis and increasing resting energy expenditure. This means the capsaicinoids inside the capsicum fruit extract help convert stored fat into free fatty acids that can be consumed by the body for energy."
However, Nastasi notes a shortfall in effective dosage of capsaicinoids similar to that of α-Lacys Reset.
"Capsimax contains only 2 percent of the capsaicinoids known for appetite suppression and lipolysis, which means each pill contains 0.16 milligrams of this active ingredient instead of the 2-milligram effective dose. To be effective, each pill would need to contain 100 milligrams of the Capsimax capsicum fruit extract," he says.
The other ingredients include black pepper extract, which is included to increase the body's absorption of the other active ingredients, and niacin. According to Nastasi, the likely reason for including niacin is a "niacin flush" that may have more to do with perception than reality.
"It's an effect that may cause your skin to redden, tingle and become warm to the touch," he says. "This will give consumers the perception PhenQ is working, despite niacin having no current scientific correlations with weight loss."
Chromium is an essential mineral nutrient that regulates carbohydrate and fat metabolism. The recommended dietary intake of chromium is 25 micrograms per day for women and 35 micrograms per day for men.
"Chromium picolinate is included in PhenQ at a dose of 10 micrograms, which is an effective amount since you can consume the rest of your daily chromium requirement through your diet," says Nastasi. "That being said, when reviewing multiple studies using chromium picolinate in the context of weight loss, they all reported the supplementation had no demonstrated beneficial effects on weight loss."
Nastasi says caffeine is included in PhenQ due to its role as an appetite suppressant and thermogenic fat burner.
"Caffeine dosages of 4 milligrams per kilogram of bodyweight (or about 290 milligrams for a person weighing 160 pounds) have been shown to significantly increase metabolic rate for three hours after ingestion," he says. "Obviously, the 75 milligrams of caffeine in one PhenQ pill is significantly lower than 290 milligrams. On the other hand, taking the recommended two pills per day (one with breakfast and one with lunch, for 150 milligrams total) should still bring some metabolic benefits while helping you stay below the daily caffeine limit of 400 milligrams recommended by the FDA."
Nastasi says another positive correlation with weight loss is caffeine's ability to reduce feelings of fatigue, not only helping people get to the gym, but also increasing the duration of their workouts.
Cactus fiber is associated with fat loss because of its ability to bind to dietary fat, according to Nastasi. "This results in the reduced absorption of fat consumed through the diet, which in turn leads to a reduction of body weight. The study demonstrating these beneficial results used two tablets containing 500 milligrams of standardized cactus fiber taken three times daily with breakfast, lunch, and dinner,” Nastasi says. “This resulted in a total cactus fiber intake of 3,000 milligrams per day. By those standards, the 20-milligram dose of nopal cactus fiber in a serving of PhenQ is unlikely to produce noticeable weight loss results."
Carnitine has been linked to weight loss through its involvement in fatty acid metabolism, says Nastasi. "Essentially, L-carnitine transports fatty acids into cells to be broken down and used to produce energy. A 2020 meta-analysis looked at 37 randomized controlled clinical trials and concluded L-carnitine did provide a modest reduction in body weight at a dose of 2,000 milligrams per day when compared to a placebo."
However, Nastasi notes PhenQ contains 150 milligrams of L-carnitine fumarate per pill, significantly lower than the 2,000 milligram effective daily dose.
InnoSlim is one of the new ingredients in the updated formula, with 125 milligrams per serving. The PhenQ website describes it as a patented blend of the herbs ginseng and astragalus shown to stimulate the release of fat-burning hormones and reduce intestinal absorption of carbohydrates (although independent research on the combination of ginseng and astragalus is limited).
The new formula also includes vitamins B3, B6 and B12, in the following amounts per serving:
Research links B vitamins with benefits including healthier metabolism and increased energy.
Iodine, at 75 micrograms per serving (50 percent daily value), is another addition to the PhenQ formula. The trace element iodine helps regulate metabolism and is necessary for the production of the body's main thyroid hormones.
We consulted with Pete Nastasi again to share more important information about PhenQ diet pills, including potential side effects, who should (and should not) try them, and more.
PhenQ contains only natural ingredients and is generally considered to be free of side effects when using the daily two-pill dosage. That being said, consumers who are sensitive to certain ingredients may experience mild symptoms, including bloating, lightheadedness, increased heart rate, insomnia, and headaches. The majority of these symptoms are associated with caffeine sensitivity and are the reason you should avoid consuming additional sources of caffeine when using this product. If you have any preexisting health conditions or experience any side effects when using PhenQ, it’s recommended you consult with your primary healthcare provider before taking or continuing to take it.
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Like similar products, PhenQ weight loss supplements are not magic pills. You will need to combine this supplement with a well-balanced weight loss program, consistent exercise, and a quality sleep schedule to experience the best results. The key to any weight loss regimen is maintaining a calorie deficit so you’re burning more calories than you’re consuming.
PhenQ claims more than 190,000 customers have used PhenQ fat burner pills and come away satisfied. The PhenQ website features several customer testimonials with before and after photos and claims including:
Of course, the testimonials carry the disclaimer "Results vary from person to person." Still, the testimonials about PhenQ results seem genuinely enthusiastic. They're evenly split between 4/5 stars and 5/5 stars.
Outside of the PhenQ website, the reviews are a mix of positive and negative experiences.
The most common negative reviews involve encounters with customer service. Some customers experienced issues with receiving their order in a timely manner, and others say PhenQ did not honor their 60-day money-back guarantee and made it extremely difficult to process a return.
Be sure to read the fine print regarding the money-back guarantee. It stipulates you must “return the first two empty bottles of your 60-day PhenQ supply and any additional unopened bottles of PhenQ within 67 days of receiving the order (60-day trial plus one week return shipping).” If you return your PhenQ within 67 days of receipt, they promise to refund you the entire purchase price minus shipping charges. Given the negative reviews about returns, we suggest purchasing this product only if you're truly committed to using it.
As with all weight loss supplements, the results will vary significantly from person to person based on a number of different factors, such as your starting weight, exercise regimen, diet, metabolism, age, gender and overall health. In the positive reviews, many consumers do note the use of PhenQ pills in addition to a healthy diet and regular exercise helped them achieve their individual weight loss goals.
PhenQ is available for purchase only through the company’s official website. The website urges consumers not to shop for PhenQ elsewhere to avoid buying "cheap, counterfeit" products.
PhenQ comes in 60-pill bottles. Depending on how much of the product is in stock, the number of bottles per household may be limited. See the website for full details.
PhenQ currently offers three purchase options, with discounts if you order more than one bottle at a time. If you buy two bottles, you get a third bottle for free. If you buy three bottles, you get two additional bottles free for a total of five.
Payment options on the PhenQ website include Visa, Mastercard, American Express and virtual wallet Skrill. Delivery is free worldwide.
While PhenQ is designed to be taken twice daily to help burn fat, PhenQ PM goes to work while you rest. It's a stimulant-free fat burner engineered to support the body’s fat-burning functions that take place while resting, such as thermogenesis and restorative sleep. In contrast, caffeine is a key ingredient in PhenQ, so it should help you feel more awake and energetic.
In addition to PhenQ weight loss supplements, the brand also offers the PhenQ Complete Meal Shake. It's a low-calorie, high-protein formula the brand claims will help improve energy and reduce food cravings.
Fat burners are weight loss supplements that promote the breakdown of fat stores in the body, a process known as thermogenesis. PhenQ qualifies as a fat burner because its formula includes ingredients that promote a thermogenic effect—primarily α-Lacys Reset and Capsimax powder.
As with all dietary supplements, it’s recommended to consult with your primary healthcare provider before adding them to your routine. This is especially important when considering the use of fat burners, since they often contain ingredients that act as diuretics and typically have very high levels of caffeine.
As long as you take PhenQ as recommended (no more than two pills per day), then you should be able to take it daily without needing to cycle on and off. PhenQ recommends taking the product for at least 60–90 days. If you have a significant amount of weight to lose, it may be beneficial to use PhenQ for a longer period of time. If you’re sensitive to certain ingredients in the formula, such as caffeine, consult your doctor first and listen to their recommendation for how long to use this product before taking a break.
Although dietary supplements are not FDA-approved for safety, PhenQ is considered safe if used as advised on the supplement facts label. If you do experience any side effects, stop using PhenQ and consult with your primary healthcare provider.
Each PhenQ pill contains 75 milligrams of caffeine—a little less caffeine than an eight-ounce cup of coffee, according to the FDA. If you take the recommended dosage of two pills a day, it's roughly equivalent to adding two small coffees to your daily caffeine intake.
PhenQ doesn’t contain any ingredients that act as laxatives and shouldn’t cause diarrhea. If you experience any gastrointestinal distress, stop using PhenQ and consult with your primary healthcare provider.
For best results, you should consume a well-balanced, nutritious diet when using PhenQ and pursuing your weight loss goals. The FDA recommends a diet that prioritizes minimally processed foods, including fruits, vegetables, healthy grains, and legumes, and avoiding high-fat, highly processed, and fried foods. This diet, in conjunction with regular exercise and the use of PhenQ, may result in healthy weight loss.
PhenQ does have the ability to impact sleep due to the amount of caffeine in each pill. When using a weight loss supplement like PhenQ, monitor your total caffeine consumption throughout the day to prevent any unwelcome side effects like anxiety and insomnia. The recommended daily allowance (RDA) for caffeine ingestion in adults is 400 milligrams, and PhenQ advises not taking a pill after 3 p.m. to avoid any interference with your normal sleep schedule.
Like any fat burner supplement, you’ll really only see results with PhenQ usage when you’re also getting a healthy amount of sleep, exercise and nutrients from a balanced diet.
Since PhenQ is designed to be taken twice daily (morning and early afternoon), you should feel a slight energy boost after taking it due to the 75 milligrams of caffeine each PhenQ pill has.
You'll feel the energizing effects of PhenQ within 15–25 minutes of taking the pill. Weight loss results depend on a number of factors, including your diet, how often you exercise (and the intensity of your exercise), and how much sleep you get most nights. According to the Mayo Clinic, it's reasonable to aim to lose one pound of weight per week until you reach a healthy weight.
In almost all cases, taking PhenQ alone will not cause significant weight loss. You’ll need to use this supplement in tandem with a nutritious, well-balanced diet, regular exercise, a caloric deficit, and a quality sleep schedule to experience any real weight loss. The combination of PhenQ alongside these healthy behaviors may help you lose weight faster and more effectively than optimizing these lifestyle factors alone. Before using a diet pill like PhenQ, research as much as possible, optimize your lifestyle to the best of your ability, and consult with your primary healthcare provider.