Active PK Reviews

We investigate Active-PK to find out if this metabolic regulator is an effective tool for weight loss.

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Last updated: Dec 21st, 2022
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In this Review

Our Findings
Why you should trust us
How we evaluated Active-PK
What is Active-PK?
Does Active-PK work?
The science behind Active-PK
Is Active-PK safe?
Who might benefit from Active-PK
Pricing
Alternatives to Active-PK
Weight loss supplement ingredients: alternatives
FAQ about Active-PK
Sources
Active PK Header

Our Findings

Editor's Rating4.00

You’re likely to experience more energy with Active-PK, but you’ll still need to implement lifestyle changes to see weight loss results. The surprisingly safe AMPK-boosting supplement uses a simple formula without stimulants or the risk of dangerous side effects common in weight loss supplements. However, this commitment to safety means that two of its three ingredients come in underwhelming doses.

Pros

  • Boosts daily energy levels

  • May boost weight loss (but not on its own)

  • No caffeine or other stimulants

  • Low risk of side effects

  • Supports long-term health, not fast fixes

  • 90-day money-back guarantee

Cons

  • Pricier than some alternatives

  • Some ingredients have questionable doses

  • Interacts with several medications

  • Not vegan-friendly

Healthy weight loss is hard. Between 2013 and 2016, almost half of all adults in the U.S. dieted,¹ but only a few (between 5% and 20%, depending on the study) successfully lost all the weight they wanted and kept it off long-term.² People struggling to lose weight may look for alternative methods to help them get to a healthy, comfortable size, and supplements are one of the first places many turn. The market is flooded with products that claim to burn fat, boost energy, and reduce cravings but often suffer from dangerous or ineffective ingredients and high prices.

We looked at Active-PK, an herbal, stimulant-free supplement that claims to melt fat by accelerating the body’s production of the enzyme AMPK. Read our full review below to learn about the pros, cons, and science behind Active-PK, so you can decide if this supplement might be the right step for you.

GREAT PICKS FROM ACTIVE PK

Why you should trust us

Innerbody Research has helped millions of readers over the past two decades make more informed decisions about staying healthy and living healthier lifestyles. This is especially true when it comes to supplements, an industry that is only lightly regulated by the FDA.

Active-PK is an energy-boosting and weight loss supplement designed and produced by LCR Health. Our team at Innerbody Research has spent hundreds of hours researching, testing, and comparing supplements in both categories. We know the big names and the common formulas, as well as upcoming brands, potentially dangerous ingredients, and ways manufacturers try to slip less-than-stellar products under the radar. While no one on our team has used Active-PK, we were able to draw from copious comparative research and our knowledge of the field to give you our assessment of their value. For this guide alone, we referenced more than 40 additional journals, studies, and trusted sources.

Like all health-related content on this website, this review has been thoroughly vetted by members of our Medical Review Board for accuracy, and we monitor developments to keep our content up-to-date.

How we evaluated Active-PK

We judged Active-PK on four key parameters we use to analyze all weight loss supplements: what it’s made of, how well it works (for real people and in clinical studies), if it’s safe, and how much it costs.

Ultimately, we found that Active-PK is a very reasonable supplement. It doesn’t quite live up to the expectations set by its manufacturer, LCR Health, but it is likely to boost your day-to-day energy levels. It may help you lose weight, particularly if you have high levels of visceral fat or insulin resistance, but its invigorating effects are more likely to give you enough energy to follow through on long-promised workouts. Its ingredients are clinically effective for at least one promised effect, though dosages may not meet standards set by researchers.

LCR Health offers a good return policy that ensures you’ll have enough time to see if you benefit from Active-PK before returning it. And while it is a little expensive, it costs significantly less than other effective weight loss and energy-boosting supplements.

Effectiveness

Rating: 8 / 10

Active-PK somewhat follows through on its promises. It appears to boost energy, though it doesn’t work overnight, and it likely won’t provide any life-changing benefits. Weight loss is secondary to Active-PK’s main benefits, and is most likely to occur if your weight gain is a byproduct of another condition or if you need extra help getting to the gym. However, taking it as a healthy person without supplementing with a healthier diet or more movement isn’t likely to do much. Two of its three ingredients aren’t as potent as they could be, which would help to improve both its energy-giving and weight-loss properties, but that would also run the risk of adding other side effects and complications. LCR Health has played it safe with Active-PK, but it still does a lot of what it advertises (which is more than we can say about a lot of weight loss supplements).

Safety

Rating: 8.5 / 10

Weight loss and energy-boosting supplements can be dangerous. They often include long lists of sketchy ingredients with little research and plenty of side effects. Active-PK does the exact opposite in their formula, focusing on three high-quality and research-backed ingredients. They cite six scientific studies that show where they got their information and allow you to evaluate for yourself whether or not Active-PK might work for you. None of Active-PK’s three ingredients have many side effects, especially in the relatively low doses present in Active-PK. However, there are many medications it may interact with, from warfarin to Wellbutrin, so check with your provider before starting Active-PK.

LCR Health makes all of their products in a facility that meets Good Manufacturing Practice (GMP) guidelines set by the FDA and has added third-party random independent testing to ensure each batch’s quality and potency match what they advertise. We believe this demonstrates an ongoing commitment to customer safety.

Cost

Rating: 7.5 / 10

Active-PK isn’t the cheapest supplement on the market. However, weight loss supplements can get expensive fast when they include high-quality ingredients, and cheaper supplements don’t always have ingredients that work. Active-PK balances efficacy with cost, giving you a mid-range option for something that works without costing an arm and a leg.

One month’s supply costs $46.99, an increase of a little more than $7 since we first looked at Active-PK in 2021. This does move it toward the more expensive end, which is less than ideal, but LCR Health has stepped up some of their safety measures in return. We’ve put together a small chart showing the cost of some other weight loss and energy supplements in comparison to Active-PK below.

Because it can take a while for Active-PK’s true effects to occur, LCR Health offers a generous and flexible 90-day money-back guarantee. This grants you enough time to try it and see whether or not it actually works for you before having to commit to a nearly $50 monthly purchase, which is a big plus.

Ingredients

Rating: 8 / 10

Active-PK has three main ingredients: Gynostemma pentaphyllum extract, quercetin, and berberine HCl. All three of these have multiple robust studies suggesting they can affect human AMPK production to different extents. Gynostemma pentaphyllum provides the most benefit, followed by berberine HCl (which is available at one-fifteenth of the clinically accepted average dose). Quercetin has some impact but appears to support cardiovascular health more than AMPK or weight loss, though studies have shown that it moderately supports AMPK production. It also contains three ingredients that preserve its quality and add useful fatty acids. Most weight loss and energy-boosting supplement ingredient lists are longer and include more experimental ingredients in higher quantities, so LCR Health plays it safe here (literally).

While its ingredients are a little sparing — Gynostemma is the only one available at a dose known to work consistently for most people — they are added in good faith and with solid research behind them. You may find that you need to add a berberine supplement to this mix to make up for Active-PK’s low dose, particularly if you have insulin resistance or are worried about visceral fat.

What is Active-PK?

Active-PK is a dietary supplement for those seeking to lose or maintain a healthy weight. It’s designed to increase your average energy by boosting your AMPK levels, helping you get to the gym, through a workout, and back to the rest of your day without hassle. According to LCR Health, Active-PK can:

  • Decrease abdominal fat
  • Boost natural energy
  • Promote clear thinking
  • Minimize cravings
  • Support a strong body

It is caffeine-free (rare for weight loss supplements) and dairy-free, so it’s accessible to most people, though it isn’t completely vegan. The supplement contains three primary ingredients:

  • Gynostemma pentaphyllum extract: 450mg
  • Quercetin: 100mg
  • Berberine HCl: 100mg

Active-PK also contains rice flour, hypromellose (instead of gelatin), and a small amount of vegetable-based stearic acid (a natural fatty acid).³ It comes in bottles of 60 capsules for a one-month supply. Taking the two-capsule dose is easy and convenient, as you can take it at any time of day with food or on an empty stomach.

Its manufacturer, LCR Health, is a Los Angeles-based nutraceutical company that makes 13 supplements (including Active-PK) to improve energy, cellular function, strength, and mobility. According to LCR Health, these supplements might also assist in detoxification and weight loss. (Detoxification claims don’t often mean much, as there’s no reason toxins would build up if you have a healthy liver and kidneys.)⁴

If you want to know more about the ingredients LCR Health used to develop their formulas (and why they were chosen), they have a webpage dedicated to different scientific studies divided by ingredient, and six citations to relevant studies on the Active-PK page. The three studies they used to pick ingredients for Active-PK include:

While LCR Health may not be a well-known supplement brand, their primary co-founder, Dr. Rand McClain, is a medical doctor who did his residency at the University of Southern California. He now runs a Regenerative & Sports Medicine clinic in California that treats the rich and famous, including professional athletes, CEOs, and celebrities.

Does Active-PK work?

We didn’t try Active-PK ourselves. Instead, we’ve relied on scientific studies, what we heard from customers, and our own knowledge of the industry to determine that Active-PK works to a certain extent.

Combined with a healthy diet and regular exercise, Active-PK has a good chance of improving your energy and increasing how much weight you lose. It may or may not help you burn visceral fat — a high-risk fat that sits around your organs and concentrates in the abdomen — depending on your medical conditions and health, but your overall fat loss still depends on your diet and activity level.⁸ Like all weight loss supplements, Active-PK doesn’t work alone.

Visceral fat can be hard to measure and can only truly be seen using CAT or MRI scans, so it’s difficult to determine whether or not Active-PK actually can burn through it. However, because Active-PK includes ingredients that are supposed to improve insulin resistance and conditions that cause it (like polycystic ovarian syndrome, also known as PCOS, or type 2 diabetes), the scale is tipped in your favor. Insulin resistance is correlated with high amounts of visceral fat, and improving insulin sensitivity can help your body process and remove some visceral fat.⁹

Active-PK’s energy boosts — without any buzzy feelings you might get from stimulants like caffeine — are its biggest draw. Because of our natural decline in AMPK over time, Active-PK seems to work better in older adults than younger people. Most people experience more energy while taking Active-PK, whereas weight loss is a less common (but still reasonably prevalent) effect. Most energy and weight loss supplements tend to focus on short-term symptom resolution, so Active-PK’s emphasis on your long-term health helps it stand out.

Don’t expect results overnight. It takes time for Active-PK to work, and most people report feeling the first effects (which generally start with increased energy) within about two weeks. Maximum impacts (including weight loss) occur during the second month. LCR Health’s 90-day money-back guarantee is a great fit for this timeline, so if you hit 2 ½ months and still don’t feel like you’ve seen any results, you can still return your bottles for a full refund.

The science behind Active-PK

Active-PK promotes fat burning by activating the enzyme AMPK in the body. AMPK (AMP-activated protein kinase) is a natural cellular energy sensor and metabolic regulator.¹⁰ When we add more AMPK with stress, exercise, or a supplement, it increases the breakdown rate of glucose and fatty acids and conserves energy from non-essential processes like making proteins and digesting food.¹¹ This means that you’re burning more calories, particularly from storage, and slowing down how much energy you’re putting away for later (which is why researchers think AMPK can influence weight loss).

There’s still a lot that medical experts are learning about AMPK’s role in the human body, but we know it has a wide-ranging effect on our health. Researchers have also studied AMPK-boosters as therapeutics for diseases¹², including cancer¹³ and metabolic syndrome.¹⁴ (Cancer has a complicated relationship to AMPK, as a little bit can improve the odds of not developing a tumor, but too much can make tumors that are already there grow faster.)¹⁵ It may also play a role in cardiovascular diseases.¹⁶ Importantly, AMPK production declines with age, so young adults have naturally higher levels of AMPK.

AMPK-boosters appear in several weight loss products based on their ability to diminish appetite and increase the body’s metabolism, leading to the efficient conversion of fat into energy. Active-PK and other AMPK boosters create a false sense of stress that revamps your body’s AMPK production and utilization, increasing your baseline metabolic rate.

Below, we’ll look at the three active ingredients in Active-PK and how they work together to ramp up AMPK production and boost metabolism.

Gynostemma pentaphyllum leaf extract (450 mg)

Gynostemma pentaphyllum is the primary ingredient in Active-PK. This extract, derived from the leaves of an herbaceous vine native to South and East Asia, has been used for centuries in traditional Chinese medicine to treat inflammation, diabetes, and cardiovascular disease.

Today, scientists study Gynostemma pentaphyllum for its anti-obesity effects.¹⁷ It’s demonstrated the ability to reduce total abdominal fat and BMI in subjects without significant side effects. Interestingly, some studies have noticed that it’s best at decreasing gynoid fat (around the hips and thighs) in women and visceral fat (on top of organs) in men.¹⁸ It also appears to balance glucose absorption, even in participants with insulin resistance,¹⁹ and decrease inflammation linked to obesity and difficulty losing weight.²⁰ And most importantly, it effectively activates AMPK.

Most of these studies were performed in mice. However, human studies are showing that — so far — these same findings track across species. For the most part, these studies use between 400mg-500mg of Gynostemma pentaphyllum extract, meaning Active-PK’s dosing accurately reflects successful clinical efforts. No known contraindications or toxicities are associated with Gynostemma pentaphyllum, making it a safe ingredient for just about everyone.

Quercetin dihydrate (100 mg)

Quercetin is a bioflavonoid that colors many plants (including onions, apples, and berries, along with other fruit, veggies, and flowers).²¹ It’s a strong antioxidant that seems to have anti-inflammatory²² and potential anti-cancer properties.²³ As an antioxidant, it:

  • Reduces inflammation
  • Protects against oxidative stress
  • Boosts immunity

These measures may also treat certain cardiovascular diseases (a bold statement backed up by many research studies, mainly focusing on cardiac arrhythmias),²⁴ reduce blood pressure,²⁵ and improve cognitive dysfunction after traumatic brain injuries.²⁶ There aren’t many studies that look at quercetin’s role in obesity and metabolic syndrome, but those that do suggest that its anti-inflammatory properties are what allow it to support weight loss. A 2019 meta-analysis, however, indicates that quercetin doesn’t significantly affect weight loss, so researchers are still undecided about if it might change your weight.²⁷

Still, some findings indicate that quercetin effectively activates AMPK signal pathways, ultimately leading to fat loss.²⁸ (It’s better at improving nerve pain from diabetic neuropathy through AMPK than weight loss, though.)²⁹ Most studies with favorable results give participants anywhere from 100mg to 1,000mg of quercetin dihydrate daily, so Active-PK’s dosing is on the lower end of expected.

Berberine (100 mg)

Berberine is a derivative of the Berberis aristata root, a medicinal herb traditionally used in Ayurvedic medicine to treat diarrhea, bacterial infections, and more.³⁰ It has antimicrobial³¹ and anti-inflammatory properties and may play a role in suppressing tumors in some kinds of cancer.³² Several studies suggest that berberine has these effects because it regulates AMPK pathways.

However, berberine is best known for its impacts on insulin resistance, shown in a 2021 study to slow pre-diabetes development into type 2 diabetes.³³ Because insulin resistance can make it easy to gain and difficult to lose weight, berberine’s ability to increase your insulin sensitivity can help your body shed excess weight naturally. In one randomized, double-blind, placebo-controlled clinical trial, adding 1,500mg of berberine daily for three months led to the remission of metabolic syndrome and reduced waist circumference, blood pressure, and insulin secretion.³⁴ Some suggest berberine works just as well as prescription medication like metformin, though researchers are still investigating this comparison.³⁵

Most clinical studies use anywhere from 300mg to 2,000mg of berberine daily, and most people feel the benefits between 900mg and 1,500mg daily. Active-PK’s low 100mg dose is likely not enough to see many of berberine’s positive effects.

If you want to take Active-PK but know that you struggle with insulin resistance, adding another berberine supplement to get your daily intake closer to clinically-studied levels might be a good option. You can learn more about them — and our favorite brands — in our guide to the best berberine supplements.

Is Active-PK safe?

Active-PK is generally safe for healthy adults. Because supplements are regulated differently than food and prescription medication by the FDA, it's up to the manufacturers to be transparent about their practices and ingredients. This doesn't always happen, but LCR Health does a decent job with its transparency. Other supplement manufacturers that have stronger safety measures might do things like making their testing results widely available, but LCR Health doesn't hide any ingredient dosages and cites studies that explain why they used the formula they did for Active-PK.

All of the ingredients in Active-PK are present in safe quantities, so if you take two capsules daily as suggested, it's unlikely that you'll run into serious problems. In fact, Active-PK leans toward using too little rather than too much, so you’re more likely to not feel anything from Active-PK than run the risk of toxicity. There are no reported adverse effects from Gynostemma pentaphyllum, but quercetin and berberine may evoke side effects such as gastrointestinal discomfort or headaches. Specifically, you might experience:

  • Diarrhea or constipation
  • Stomach pain and cramping
  • Nausea
  • Headaches
  • Hypoglycemia

Again, there isn't very much quercetin or berberine in this supplement, so your chances of experiencing these side effects are relatively low. Most side effects occur when you start taking Active-PK, but they go away within a few weeks as your body adjusts. However, some groups should stay away from Active-PK because of its potential to interfere with certain medications and medical conditions. (We’ll get into who this is in the next section.) Always check with your doctor before starting a new supplement.

All of LCR Health’s products are made in GMP-certified facilities in the United States, as we expect from high-quality supplements. More recently, LCR Health has added independent third-party testing to their manufacturing regimen: a random sample from each product batch is sent to a third party for purity, potency, and safety testing, ensuring that Active-PK is safe and high-quality as advertised.

Who might benefit from Active-PK

Because it’s generally safe with minimal side effects, many healthy adults who want to lose weight or increase their energy could safely try Active-PK. LCR Health suggests that people who experience the following might find the most benefit from Active-PK:

  • Rapid weight gain
  • Brain fog
  • Lack of physical energy
  • Difficulty engaging in favorite activities

These symptoms are common among a massive landscape of medical concerns, from depression to ovarian tumors, so check with your doctor before starting Active-PK to rule out any serious medical problems. If you’re looking for dramatic weight loss, however, Active-PK might not be right for you, as it’s better at boosting energy than dropping pounds.

Older adults trying — and struggling — to lose weight or gain energy and strength are the most likely to benefit from Active-PK and other AMPK-boosting supplements. AMPK stores decline as you age, propelling your loss of muscle mass and strength. This makes it more difficult to lose weight through exercise and makes you hold onto the weight you’ve already gained, as muscles burn more calories than fat.

Who should stay away

While Active-PK has very few side effects, most problems occur when Active-PK mixes with another medication. There are some situations where it’s not a good idea to take this supplement, too. Those with a history of eating disorders should use caution when taking Active-PK because of its weight loss-promoting qualities. And because it’s unclear why increasing AMPK can speed up tumor growth, people with cancerous or benign tumors should steer clear of Active-PK.

Gynostemma has minor anticoagulant effects, so you should stay away from Active-PK if you’re on a blood thinner like warfarin.

It can be dangerous to take berberine if you have hypoglycemia or are already on diabetic medication like insulin or metformin because the herb is so good at lowering high blood sugar. Talk to your doctor before starting Active-PK if you take one of these medications, and keep an eye on your glucose readings. You may need to adjust your insulin use while you’re taking Active-PK.

If you’re taking a medication that warns you not to eat grapefruit while on it, you shouldn’t take Active-PK either. That’s because berberine (and grapefruit) interacts with liver enzymes that break down certain medications, leading to either too much or too little in your system. Other kinds of medications that interact poorly with the berberine in Active-PK include (but aren’t limited to):

  • Immunosuppressive medications
  • Macrolide antibiotics
  • Phosphodiesterase inhibitors

Quercetin can cause kidney damage in high doses (1g or more daily). Luckily, Active-PK adds only one-tenth of this amount of quercetin to its formula. Still, you shouldn’t combine it with other quercetin-containing supplements. People with kidney disease shouldn’t take Active-PK for that reason, either.

People who are pregnant or breastfeeding should stay away from Active-PK. Likewise, Active-PK is not appropriate for children under 18.

Pricing

Active-PK comes in one size bottle at one dose (60-capsule, 30-day supply at 650mg). This makes it incredibly easy to figure out how much you’ll pay. You can purchase Active-PK through Amazon or LCR Health, but we recommend buying directly from the company website to ensure you’re eligible for the full 90-day money-back guarantee. This guarantee protects your purchase for three months, so if you aren’t feeling the effects or it doesn’t agree with you, you can reach out to LCR Health’s customer support team via email or phone for your money back.

LCR Health does not automatically offer any subscription service for its products, so you’ll need to remember to reorder it before you run out. Subscription services are convenient, so it’s a little disappointing that they don’t offer them to everyone. However, as an Innerbody reader, you can unlock autoshipments with a 10% discount by purchasing through one of our affiliate links. All automatic shipments come with free shipping, and they’re delivered (and charged) once a month. Canceling is easy, too — just email LCR Health’s customer service to let them know you’re done.

No matter how you purchase Active-PK, you can earn significant savings by buying Active-PK in bulk. We recommend going for the three-bottle bulk deal if you’re trying Active-PK for the first time. This lowers your price out-of-pocket and keeps the number of purchases simple in case you need a refund.

As seen in the chart below, purchasing the six-bottle bundle drops the price per serving from $1.57 to $1.20. This chart reflects the standard pricing for a one-time order and the 10% discount you can earn by joining the subscription program through our links.

On average, weight loss and energy boosting supplements tend to cost between $20 and $55 with most high-quality supplements in this field costing about $40 for a one-month supply. HUM Nutrition’s Skinny Bird costs $40/month, whereas apple cider vinegar supplements and Hydroxycut are closer to $20. Active-PK used to be exactly average, but these prices have slowly crept up with time. They’ve gone up about $7 per bottle since we last reviewed them in 2021, so keep an eye on LCR Health’s website to ensure you’re still getting the best deal possible.

LCR Health provides free shipping on all orders in the U.S., except for purchasing one bottle once through the affiliate link, where you’ll pay $3.95 for shipping.

Alternatives to Active-PK

Since so many people struggle to lose weight and keep it off every year, supplements that promise to help you shed extra pounds are everywhere. However, few actually work, and those that do are often prohibitively expensive and require jumping through extra hoops to get a prescription. Active-PK balances both of these considerations, but maybe you have a little bit more money to spend and want a higher-quality supplement. Or, maybe you’re on a budget but need nutritional support above and beyond a healthy diet. Either way, there are other options than Active-PK.

Above all, we still recommend a healthy diet and regular exercise as the number one way to assist in your weight loss journey. If you are genuinely struggling to lose weight at a healthy pace, get in touch with your doctor. You might need to see an endocrinologist, nutritionist, dietician, or therapist to overcome your struggles. There are many common diseases and disorders that make it difficult to lose weight, including (but not limited to):

  • Hypothyroidism
  • PCOS
  • Diabetes
  • Depression
  • Chronic stress

Since everyone deserves to be happy and healthy at a weight that feels good, we’ve laid out some alternatives to Active-PK (including a familiar face we don’t recommend and why).

Energy-boosting supplements

Active-PK’s primary benefit is the way it can increase your energy, but AMPK isn’t the only thing that can put a stop to your sluggishness or fatigue. In fact, fatigue is one of the most common side effects of several kinds of vitamin and mineral deficiencies, most notably vitamin D, magnesium, iron, and B-complex vitamins (especially B2, B3, and B12). If Active-PK doesn’t help you regain energy, it’s possible you have a vitamin deficiency or need a boost in another aspect of your life, like poor sleep habits that leave you feeling drained. A good multivitamin could even improve your energy levels and round out the nutritional deficiencies induced by a low-calorie diet. And if the cause of your fatigue is a mystery, there are plenty of general energy-boosting supplements that could help you out.

Some ingredients that are known to have energy-boosting properties include, but aren’t limited to:

  • Ashwagandha
  • Rhodiola rosea
  • Melatonin
  • CoQ10
  • Creatine
  • Caffeine
  • L-Theanine
  • Citrulline
  • L-Tyrosine
  • NAD+
  • Ginseng
  • N-Acetyl L-Carnitine

Pre-workout supplements are a good alternative if you need more energy to hit the gym consistently and do your full workout once you’re there. They contain amino acids that are good for building muscles and a plethora of other vitamins, minerals, and herbs for energy and recovery. One popular pre-workout, Cellucor C4 Ripped pre-workout powder, comes in seven different flavors and contains:

  • Vitamin C
  • Vitamin B3
  • Vitamin B6
  • Vitamin B12
  • Beta-alanine
  • Citrulline

It also contains two proprietary blends (C4 Ripped Performance & Thermogenic, which contains things like cayenne and green coffee seed extract, and Explosive Energy blend, which has 150mg of caffeine and 50mg of L-Dopa). If you’re looking for a quick boost of energy with a sweet taste, this pre-workout powder fits the bill. It isn’t the healthiest supplement out there, but it’ll get the job done at a slightly lower cost ($40 for 30 servings).

C4 Ripped comes on stronger and wears off faster; Active-PK is better for a slow, long-lasting energy boost. Both are relatively equally likely to help you lose weight if you're healthy, but C4 Ripped pre-workout is more likely to do that through boosted muscle productivity. In contrast, Active-PK is more likely to help with clinical deficiencies and conditions like type 2 diabetes. If you're worried about visceral fat, go with Active-PK.

If you’re looking for an herbal energy boost, NOW Supplements Energy provides a robust list of vitamins, minerals, and herbs, as well as 64mg of caffeine. That’s about half as much as other caffeinated energy supplements, and this vegan, allergen-free supplement contains a robust ingredient profile:

  • Vitamin B complex (B1, B2, B3, B5, B6, B12)
  • Vitamin E
  • Iodine
  • Chromium
  • Potassium
  • Guarana extract (44mg caffeine)
  • Green tea extract (16mg caffeine)
  • Ginseng root
  • Organic eleuthero root
  • Rhodiola rosea
  • Licorice root
  • Gotu Kola
  • Yerba Mate extract (4mg caffeine)
  • Cayenne
  • Alpha-lipoid acid
  • CoQ10

Many of these ingredients support adrenal health as much as — if not more than — overall energy. Adrenal fatigue is another way you’re likely to run into unanticipated exhaustion, so if you’ve been dealing with chronic stress, these capsules might be a good fit for you. They’re significantly less expensive than Active-PK (costing about $22 for 45 servings), and you can find them in some brick-and-mortar retail stores if you want to start today. However, they have no effect on weight loss.

Thermogenic weight loss supplements

Fat burners, also known as thermogenic fat burners or thermogenics, can help you lose weight efficiently. They’re designed to increase your metabolic rate and suppress your appetite, so your body works harder to burn more calories than you’re taking in. Fat burners are focused exclusively on melting pounds, and AMPK boosters have a bigger range of impact on your health.

Boosting your AMPK levels can increase your metabolism, but that isn’t Active-PK’s (and other AMPK-boosting supplements’) only goal. If you don’t make enough AMPK, they might increase your energy levels and improve your quality of life well into old age. AMPK boosters generally have fewer uncomfortable side effects like nervousness, sweating, jitters, and elevated heart rate commonly associated with fat burners. Fat burners also have a longer list of potentially dangerous ingredients and situations where they aren’t appropriate. In contrast, you’ll generally only need to avoid AMPK-boosting ingredients if you have kidney or liver problems or cancer, or if you take certain medications.

One common thermogenic fat burner is Burn XT, made by the brand Jacked Factory. This supplement is made from:

  • Acetyl-L-carnitine
  • Caffeine (green tea leaf extract and 135mg caffeine)
  • Cayenne extract (capsaicin, a potent thermogenic)
  • BioPerine (black pepper extract)

Black pepper extract increases the bioavailability of other ingredients, and acetyl-L-carnitine turns long-chain fatty acids into energy, can help improve fatigue, and has few side effects. At about $30 per 30-serving container, it’s cheaper than Active-PK, but it isn’t a good option if you’re sensitive to stimulants.

You can read more about our favorite thermogenic fat burners here.

Prescription medications

If you struggle with losing weight and have a high BMI, you might be eligible for prescription weight loss medication. These are regulated by the FDA and are highly effective, with years of clinical research necessary to prove both their efficacy and safety before they reach you.

Some prescription weight loss medications include tirzepatide, semaglutide (Wegovy), phentermine/topiramate (Lomaira), and orlistat (Xenical). They’re all relatively new to the market, with semaglutide approved for weight loss by the FDA in the summer of 2021 and tirzepatide waiting on an FDA approval for weight loss as of late 2022, but they’ll likely become more prevalent and easier to access with time. For now, though, they are expensive and difficult to access, costing up to several hundred dollars a month without insurance. (In late 2022, semaglutide cost as much as $1,300 per month because of manufacturing shortages.)

Typically, prescription weight loss medication requires having a BMI over 30 (or over 27 with a condition either induced or made worse by having a high weight) and proving that you’ve tried eating well and exercising. Most of these medications affect hormones ghrelin and leptin (which control your hunger signals) or how much fat your body absorbs, except for phentermine (which works like a stimulant). None of these medications should be taken long-term. Because they are so strong, there’s a much higher chance you’ll experience side effects than you might with a more gentle supplement like Active-PK.

You can actually purchase one form of orlistat over-the-counter at many large pharmacies as its brand name, Alli. (The over-the-counter version has identical ingredients to the prescription version but is half as strong.) Alli uses 60mg of orlistat to keep the body from absorbing dietary fat, but there’s a long list of side effects associated. You’ll need to minimize the amount of fat you eat in a sitting (to 15g maximum) to avoid the more unpleasant side effects. People who should avoid Alli include those who:

  • Take any other medications (especially blood thinners, immunosuppressants, and thyroid medications)
  • Have had an organ transplant
  • Have a malabsorption disorder
  • Have pancreatic problems

However, if you are determined to lose weight, are otherwise healthy, don’t take any medication, and nothing else has worked for you, Alli may be a good option. It’s more expensive than Active-PK (about $55 for 20 servings), but you shouldn’t take it for more than a few months at a time. It won’t do anything beneficial for your energy levels, and you might find that you have less energy as a side effect, so if you want to feel more invigorated, start with Active-PK. Active-PK is better for anyone who is currently taking medication or has a health condition, as well as those who don’t have regular access to a doctor for supervision. You’re less likely to see a dramatic weight loss with Active-PK than with Alli, but it’s a much safer supplement.

Hydroxycut

Hydroxycut is a family of very well-known weight loss supplements with a troubled history. They were recalled in 2004 after the FDA banned ephedra, one of their primary ingredients, for having an “unreasonable risk of illness or injury.” Hydroxycut also used to contain several ingredients now known to cause serious liver damage and was known to trigger several heart attacks and at least one death. It was recalled again in 2009 after the death occurred (prompted by the FDA), reformulated, and went back on the market in 2013. Since then, it’s stayed out of the limelight, except for two other product recalls (for Hydroxycut Green Tea and Hydroxycut Hardcore, which were linked to the development of atrial fibrillation and ulcerative colitis, respectively) and when rapper 6ix9ine claimed to have overdosed on a double dose of Hydroxycut and coffee in October 2020.

Currently, Hydroxycut’s original formula contains:

  • Vitamin D
  • Vitamin B complex (B1, B2, B3, B6, B12)
  • Hydroxycut Weight Loss Plus Blend (coffee extract, ACV, plum, baobab extract, cardamom)
  • Energy Matrix (coffee extract)

Their use of proprietary blends isn’t great, as proprietary blends are often used in the supplement industry to hide how much of certain ingredients a product contains. We do know that it contains 400mg of coffee extract, which they claim offers about 200mg of caffeine, and with the exception of vitamin B12, all of the vitamin inclusions are between 25-50% of the average daily intake requirements.

We’d still recommend you stay away from Hydroxycut if you’re looking for a weight loss supplement. Their manufacturer’s history shows repeated marks of carelessness, and their ingredients won’t support your health long-term like Active-PK can.

Weight loss supplement ingredients: alternatives

Sometimes it feels like every weight loss supplement uses a completely different set of ingredients yet claims to have the same positive effects. Some can genuinely benefit your health, while others are nothing more than filler (or, at worst, are dangerous). We did a deep dive on the three of the most common ingredients not found in Active-PK — raspberry ketones, apple cider vinegar, and stimulants, which encapsulate both green tea extract and caffeine — so you can make an informed decision about your choice of weight loss supplement.

Raspberry ketones

Ironically, raspberry ketones aren’t only found in raspberries. This compound also can be found in other fruits, rhubarb, and pine tree bark, but most supplements use synthetic or lab-made raspberry ketones.

There’s no real evidence that raspberry ketones help you lose weight. A study from 2005 suggested that raspberry ketones prevented weight gain in mice who were eating high-fat diets and improved fatty liver outcomes, but that hasn’t been reliably replicated in humans.³⁶ Plus, some studies have found that high doses for a long period (as commonly found in weight loss supplements) can be a health hazard, increasing ALT and blood sugar levels.³⁷ We don’t recommend using raspberry ketone-based products if you’re interested in losing weight or gaining energy.

Apple cider vinegar

Apple cider vinegar (also known as ACV) has a little bit of scientific backing that suggests it can help you lose weight in combination with a low-calorie diet — mostly because ACV causes people to lose their appetite.³⁸ If you’re looking for something with appetite reduction effects, ACV might be a good option for you. However, some studies have started to suggest that ACV may be beneficial for decreasing high blood sugar; there isn’t enough research yet to say whether or not this is universally true.³⁹ And one recent study from Saudi Arabia on rats found that ACV worked better than green tea extract at decreasing weight, but not as well as prescription medications like orlistat and chitocal.⁴⁰

While you can buy apple cider capsules, gummies, or tablets, you can also just buy a plain bottle of apple cider vinegar for a few dollars at your local grocery store (one 16oz bottle costs about $4 at Whole Foods, for example). However, you’ll have to measure out 1-2 tablespoons of vinegar yourself and add it to water; drinking it straight can damage your teeth's enamel. And while ACV gummies taste better, gummies are less effective at getting nutrients into your body. We recommend taking a capsule, which both preserves the most active ACV and is easiest for your body to absorb.

No matter which form you purchase, be sure to get something that includes the mother, a portion of the bacterial culture used to make the vinegar that contains the highest proportion of beneficial protein, enzymes, and gut-friendly bacteria.

One high-quality ACV capsule comes from Bragg, a well-known brand that sells ACV straight and in a few different kinds of supplements. Their ACV capsules contain an ACV powder blend with 750mg of acetic acid, as well as added vitamin D and zinc for fatigue and immune support. That’s considerably more acetic acid than other ACV supplements offer, but you’ll have to take three capsules daily (as opposed to Active-PK’s two) with food and water. It’s also considerably cheaper than Active-PK ($20 for 30 servings).

This supplement won’t do anything to your energy levels, but if you’re just looking for an appetite suppressant that might help you lose weight a little easier, Bragg’s ACV supplement might be a good fit. We don’t recommend ACV as much as we do Active-PK for people struggling with high blood sugar and insulin resistance because medical experts just don’t know enough about how ACV influences it yet.

Stimulants

While “stimulants” might paint a picture of pharmaceutical and recreational drugs, the term also applies to common compounds like caffeine found in ingredients like tea and coffee extracts. Most of the stimulants that you’ll find in herbal supplements are caffeine-based from coffee (green coffee bean extract) or green tea.⁴¹ Caffeine indirectly affects weight loss by increasing your energy levels and suppressing your appetite, but there’s no proof that caffeine directly affects your weight.

If you want to use caffeine to push your weight loss along, it’s best to take it as black coffee, green tea without milk or sugar, or as a low-dose supplement. We specify “low dose” here because it’s relatively easy to overdose on caffeine. Healthy adults can safely tolerate up to 400mg of caffeine daily (about four cups of coffee), but caffeine can turn lethal at 5-10g daily. Caffeine overdoses are extremely unlikely, but they can happen, particularly in highly concentrated supplements.

Even if you don’t get to that point, having too much caffeine leads to many uncomfortable side effects, like:

  • Headaches
  • Nausea
  • Nervousness
  • Trouble sleeping
  • Dizziness
  • Racing heart
  • Dehydration

Green tea extract is generally a better option if you want a caffeinated supplement because it also comes with many other benefits. Green tea contains catechins, a kind of polyphenol known to help your body oxidize fat and increase metabolic rate (like AMPK), alongside caffeine, which gives it a boost.⁴² Like many other herbs, researchers are mixed on whether or not green tea can truly help you lose weight long-term. Some meta-analyses found that its effects on weight are minimal, but it can help you lose a little bit of excess fat.⁴³ Others with a more specialized population — like this recent meta-analysis of four studies looking at green tea’s effects on the weight of women with PCOS — find more convincing results (though the study itself calls it “very low-quality evidence”).⁴⁴

Nature’s Bounty Green Tea Extract is one high-quality, popular green tea supplement designed to suppress your appetite and add an incredible amount of antioxidants to your diet (green tea’s main benefit). Each serving contains 315mg of green tea extract (about a cup and a half of tea) and anywhere from 27mg-40mg of caffeine. You can purchase it from just about any large chain pharmacy in the U.S., and it’s very inexpensive compared to Active-PK (about $13 for 50 servings).

Unless you’re looking to increase the amount of antioxidants you consume, the limited amount of research on green tea and caffeine’s efficacy on weight loss means it probably won’t do much for your weight loss goals. If you like the taste of green tea, you may be better off just adding a large cup to your morning instead. Active-PK has ingredients that are more scientifically robust, and quercetin also supports heart health just as well (if not better) than green tea.

FAQ about Active-PK

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