The Best Supplements for Weight Loss in 2024: Analyzed by Experts
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As a certified nutrition coach and clinical weight loss practitioner, I can tell you that the only way to actually lose weight is to expend more energy (calories) than you consume. This is why a successful weight loss program involves a strategic combination of mindful eating, regular exercise and high-quality sleep. While these three key components are a necessity for long-term sustainable results, there are a handful of dietary supplements available that can make your road to success a more attainable and enjoyable experience.
That being said, when it comes to weight loss, there are countless diets, detoxes, cleanses and pills that promise quick fixes and groundbreaking results. Unfortunately, we know from experience that the majority of these products are a far cry from the magical fat loss solutions they claim to be. This is why it's essential to understand the science behind these dietary supplements and identify the key ingredients that will actually help support your weight loss goals.
In this article, our goal is to shed light on proven ingredients, such as capsaicin, green tea extract, chromium picolinate, caffeine and glucomannan, all of which are commonly featured in weight loss supplements for their potential to enhance metabolism, improve fat loss and contribute to an overall more effective weight loss strategy. Our hope is that you feel more informed and better equipped to find a weight loss supplement that will best support your personal health and wellness goals.
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.
Capsimax
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What it is
Capsimax is a trademarked, whole-food extract from red chili peppers used in some appetite suppressants. It's designed to improve the breakdown of stored body fat and increase thermogenesis.
How it supports weight loss
Red chili pepper extract has been shown to help reduce body weight when consumed in doses of two milligrams or greater per day. This is primarily due to capsaicin, the compound responsible for the spicy heat you experience when eating chili peppers. It is noteworthy for suppressing caloric intake, increasing thermogenesis and enhancing fat oxidation.
Possible side effects
When taken appropriately, Capsimax is unlikely to cause any negative side effects in healthy individuals. That being said, if you have a pre-existing medical condition or use the supplement not as intended, there is a potential for negative health outcomes.
Best Capsimax Weight Loss Supplement: PhenQ
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PhenQ is an all-natural weight loss supplement that's formulated to target key areas of metabolic health in order to decrease excess body fat, reduce cravings and support natural energy production. One of the key ingredients, in addition to the handful of vitamins and minerals in the product, is the 50 milligrams of Capsimax red chili pepper extract.
This ingredient, which is standardized to contain two percent capsaicinoids (CAPs), ultimately delivers one milligram of CAPs per serving. This is important because PhenQ is designed to be taken twice daily and therefore results in a total serving size of two milligrams of capsaicin per day. This amount, which has been found to be the minimum effective dose, has been shown to increase daily energy expenditure and lipid oxidation, which results in a decrease in fat stores. When paired with a healthy diet and regular exercise, this product may work to increase your fat burning potential.
Check out our in-depth PhenQ review for more information.
Green Tea Extract
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What it is
Green tea extract is derived from the leaves of the Camellia sinensis plant, the same plant from which green tea is made. It is rich in bioactive compounds, particularly catechins, which are antioxidants known for their health benefits. The primary catechin in green tea extract is epigallocatechin gallate also known as EGCG.
How it supports weight loss
Green tea extract is believed to support weight loss by boosting the metabolism and increasing thermogenesis. This is due to the combination of caffeine and catechins, which has been shown to promote the breakdown of fats for energy and increase energy expenditure. Although these results aren't anything staggering, research supports that green tea extract likely has an overall positive effect on weight loss and weight management, with minimal adverse side effects.
Possible side effects
Supplementation of green tea extract is unlikely to cause any side effects when used in moderation. Research suggests a safe intake level of less than 340 milligrams of EGCG per day to prevent any hepatotoxicity, or damage to the liver.
Best Green Tea Weight Loss Supplement: Transparent Labs Recomp
Transparent Labs
Transparent Labs Recomp is characterized as a metabolism booster and appetite suppressant. The formula contains five key ingredients, green tea leaf extract, forslean, L-theanine, capsimax and bioperine, all of which are included to help support weight loss.
What we like about this formula in particular is that it contains 300 milligrams of green tea leaf extract, and based on the label claims, 50 percent is composed of epigallocatechin gallate or EGCG. This catechin is renowned for its powerful antioxidant capacity, as well as its ability to boost metabolism, increase fat oxidation and enhance thermogenesis. In my opinion, this makes this product one of the best supplements to help lose weight because the combination of green tea leaf extract and capsimax will help the body utilize stored body fat for energy and therefore help preserve lean muscle mass.
Note: This product is not a stimulant-free fat burner, so it's not the best option for individuals who are sensitive to caffeine or consume other caffeinated products such as pre-workout supplements, energy drinks, coffee, soda or tea.
Chromium Picolinate
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What it is
Chromium picolinate is a nutritional supplement that combines the essential mineral chromium with picolinic acid, a naturally occurring substance in the body.
How it supports weight loss
Chromium picolinate supplementation may support weight loss due to its involvement in the metabolism of carbohydrates and lipids in the body. However, it is believed these effects may only be true for individuals who are deficient in this mineral nutrient. Studies using 200 micrograms and 1,000 micrograms of chromium picolinate per day have failed to demonstrate any beneficial effects on weight loss.
Possible side effects
There have been reports of negative side effects due to chromium supplementation. These primarily include diarrhea and headaches, although some case reports have described kidney damage in high doses of 1,200 to 2,400 micrograms per day for four months.
Best Chromium Picolinate Weight Loss Supplement: PhenQ PM
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If you're interested in testing out PhenQ but don't want the added caffeine, you should consider PhenQ PM. This nighttime fat burner includes a handful of amino acids including L-lysine, L-arginine, L-tyrosine and L-theanine, which may help you fall asleep faster and achieve a better sleep quality. The formula also includes choline (as choline bitartrate) and 11 different vitamins and minerals, including chromium picolinate.
This trace mineral may play a role in supporting weight loss by regulating blood sugar levels and helping to preserve lean muscle mass. That being said, the scientific evidence supporting its efficacy for weight loss is not entirely conclusive. For the best results, PhenQ advises taking four capsules approximately 30 minutes to one hour before bed. The company also stresses the importance of remaining as consistent as possible when using this supplement to best support your weight loss goals.
Check out our PhenQ PM review for more information.
Caffeine
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What it is
Caffeine is a naturally occurring stimulant that's commonly found in coffee, tea, soda, energy drinks, pre-workout powders and weight loss supplements. It is best known for its ability to reduce feelings of fatigue and ward off drowsiness by blocking the action of adenosine, a neurotransmitter that promotes sleep and relaxation. Caffeine also increases the release of other neurotransmitters, such as dopamine and norepinephrine, leading to heightened alertness, improved mood and enhanced cognitive function.
How it supports weight loss
Caffeine has been shown to help support weight loss in several ways, including boosting metabolism and thermogenesis (the body's ability to burn calories and convert them into heat), as well as enhancing fat oxidation. This allows the body to more efficiently utilize stored body fat as a source of energy, especially during physical activity.
Possible side effects
The scientific literature supports that for healthy adults, moderate caffeine consumption (up to 400 milligrams per day) is not associated with any major adverse side effects. That being said, consuming heavy doses of caffeine (over 400 milligrams per day) has been shown to increase feelings of anxiety, agitation, headaches and insomnia in certain individuals, especially those sensitive to caffeine.
Best Caffeinated Weight Loss Supplement: Legion Athletics Phoenix Fat Burner
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Legion Athletics Phoenix is a caffeinated, thermogenic supplement designed to improve fat metabolism and stimulate caloric burn by increasing the body's temperature. Phoenix has 200 milligrams of caffeine (about as much as you would intake from two cups of coffee) to help reduce fatigue, suppress appetite and enhance alertness, which may help you burn more calories throughout the day. Other key ingredients include forskolin and Caralluma Fimbriata.
Forskolin is a root extract that has been studied for its effect on body fat and appetite. One study showed it may help reduce body fat percentage while maintaining lean muscle mass in men who took 250 milligrams twice a day. (Note that this study was funded by Sabinsa Corporation, a company that manufactures, supplies and markets dietary and cosmetic ingredients and supplements.) A different 12-week study showed that forskolin may reduce self-reported hunger and increase satiety in women who take 250 milligrams daily (the amount in the Phoenix formula), though study participants had no significant differences in calorie intake or body fat percentage.
Caralluma Fimbriata is a cactus that grows in certain parts of India, and traditional medicine uses the plant as a natural appetite suppressant. One study found that taking 1,000 milligrams daily (the amount in Phoenix) may help decrease your waist circumference and lower your caloric intake. However, it should be noted that in this study, the placebo group showed the same results.
Glucomannan
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What it is
Glucomannan (Amorphophallus konjac) is a water-soluble dietary fiber derived from the root vegetable known as the elephant yam or voodoo lily. This ingredient has a long history of use in Asian cuisine and traditional medicine.
How it supports weight loss
Glucomannan is believed to support weight loss in a few different ways. Firstly, glucomannan has the ability to absorb water and swell in the stomach. This creates a feeling of fullness or satiety, which may lead to a reduction in food intake and contribute to a lower daily caloric intake. Glucomannan has also been shown to help improve insulin sensitivity and contribute to better blood sugar control, which may help reduce the likelihood of excess calories being stored as body fat. Nevertheless, the current scientific literature does not show that supplementation with glucomannan contributes to statistically significant weight loss.
Possible side effects
Individuals who supplement with glucomannan may experience some gastrointestinal discomfort which is common when shifting from a low fiber to a higher fiber diet. This side effect usually subsides within a few days of higher fiber intake.
Best Glucomannan Weight Loss Supplement: Nature's Way Glucomannan from Konjac Root
Nature's Way
Nature's Way Glucomannan from Konjac Root is a single ingredient weight loss supplement that's designed to help promote feelings of fullness. The key to its effectiveness lies in glucomannans ability to absorb water, forming a gel-like substance as it passes through the digestive tract. This glucomannan-gel adds bulk to the stomach, promoting satiety and reducing appetite. As a result, individuals may consume fewer calories throughout the day, ultimately aiding in weight management.
Additionally, glucomannan's dense nature slows down the digestion of nutrients, leading to a more gradual release of glucose into the bloodstream. This property can help regulate blood sugar levels and has been shown to be particularly effective for individuals with type two diabetes.
Each three capsule serving delivers two grams of glucomannan, a dose that has been shown to be well-tolerated and resulted in significant weight loss in overweight and obese individuals. Just be sure to take this product with adequate fluid, at least eight ounces of water, approximately 20 minutes before your meals.
Are Weight Loss Supplements Safe?
Weight loss supplements are generally safe, but it depends on the manufacturer and your medical history. The safest and best weight loss supplements are those that have been third-party tested to meet GMP and other quality assurance standards.
"When looking for an OTC (over-the-counter) weight loss supplement, it is important to consider the ingredient contents and if it contains stimulants," says Nicole Avena, Ph.D. "These are some of the most important things to consider because they will affect your overall health."
Dietary supplements are not required to be FDA-approved, but if a supplement is found to be unsafe, the FDA can issue a warning and ask that it be removed from the market.
Always consult your doctor before starting a new dietary supplement regimen.
How Weight Loss Supplements Work
Weight loss supplements work in a variety of ways, depending on the type of supplement.
Protein powders for weight loss work by providing the body with essential amino acids (EAAs) it can use to build protein. A protein-rich diet can serve as an appetite suppressant, boost metabolism and increase energy levels, providing endurance for fat-burning workouts. Protein powders may also help your body maintain muscle mass during periods of rapid fat loss.
Some weight loss supplements come in pill form. The most effective weight loss supplements contain ingredients that have been scientifically proven to support weight loss and promote a healthy metabolic rate. Another common trait of the best diet supplements is testing for safety and quality standards, including testing by independent third-party labs.
Other weight loss supplements work by offering a cocktail of essential nutrients the body can use for energy and overall vitality. Nutrient-rich supplements are especially beneficial if your weight loss diet involves a very low calorie intake, as your essential nutrient intake may be sub-optimal.
Weight loss supplements may also work by:
- Curbing food cravings
- Increasing the feeling of fullness to prevent overeating
- Boosting metabolism
- Slowing down the body’s fat production
- Preventing the body from absorbing the fat in the food you eat (fat blockers)
“Overall, their benefits are seen most often when combined with other healthy lifestyle measures, like exercise and decreased caloric intake,” says Avena.
Related Post: Do Weight Loss Pills Work?
How to Use Weight Loss Supplements
When using weight loss supplements, always follow the directions on the supplement’s label, unless otherwise directed by your physician.
Combine protein powder weight loss supplements with weight lifting and resistance exercises that promote lean muscle synthesis.
Use fat burning supplements alongside workouts that burn fat. The key to burning belly fat is to reduce your total body fat with moderate to intense physical activity.
Nutrient-rich weight loss supplements are best used with low calorie and low carb diets or fasting.
You might also benefit from using a weight loss app while taking a supplement for weight loss. Weight loss apps are designed to enhance your weight loss journey and improve your weight management in the long-run.
Who Should Avoid Weight Loss Supplements
Weight loss supplements are not for everyone. People who should avoid supplements for weight loss includes, but isn’t limited to:
- Individuals whose doctor advises against their use
- Individuals with a history of diet pill abuse or eating disorders
- Individuals with medical conditions that may be affected by supplement use
OTC supplements are often dangerous for those who suffer from anxiety, depression, and cardiovascular issues, says Avena.
How We Chose the Best Supplements for Weight Loss:
Our top weight loss supplements were chosen with input from our experts and key factors including:
- Ingredients: Contains ingredients that are shown to promote weight loss
- Active ingredient content per serving: Active ingredients are dosed in an amount that's effective
- Mechanism: Targets weight loss in a way that's effective and scientifically backed
- Third-party testing: Certification from independent labs to ensure quality and that what’s on the label is what you get
- Price per serving: A range of price points are included to fit a variety of budgets.
- Availability of subscription plans: Options to subscribe and save on up-front cost and shipping
- Customer reviews: Online ratings posted by users that are mostly positive
- Flavor options: Selection and quality of different flavors, if available
Additionally, some of our selections have been tested by our experts, and their personal experiences factor into the products' evaluations. Learn more about our product review process.
What to Look for in a Weight Loss Supplement
Finding the best supplement for weight loss that meets your individual needs can take time, as there are hundreds of options to sift through. To find a dietary supplement that aligns with your weight loss goals, look at the supplement’s ingredients, form and side effects.
Ingredients
There are dozens of ingredients associated with weight loss, each affecting the body in different ways. We mentioned many of these ingredients earlier in this article. Other common ingredients associated with weight loss include:
- Garcinia cambogia — a green fruit shown to hinder a fat-producing enzyme in animal studies
- Nopal cactus — a natural dietary fiber shown to help reduce fat accumulation by aiding the digestion of dietary fat
- Caffeine anhydrous — a dehydrated form of caffeine that may activate thermogenesis to help shed excess fat stores as energy
- Omega-3 — Studies have linked Omega-3s to improved weight management and fat loss in overweight and obese individuals
- Lacys reset — a trademarked formula that may help boost metabolic response
- Piperine — derived from black pepper; has been shown to decrease body weight and promote fat loss in animal studies
- Turmeric (curcumin) — an antioxidant that may play a role in weight loss
- L-theanine — an amino acid primarily found in green and black tea, as well as some mushrooms
What about vitamins for weight loss?
You might not think of taking vitamins for weight loss, but scientific research suggests that vitamins B and D3 should be on your radar.
- Vitamin B — Research suggests that Vitamin B combined with BCAA supplementation may have a slimming effect on the legs and waist to hip ratio in overweight and obese women
- Vitamin D — A clinical trial on vitamin D3 supplementation in overweight and obese women found that it significantly decreased body weight compared to control and placebo groups, which makes this vitamin a promising component of weight loss programs for women.
Form
Weight loss supplements typically come in the form of swallowable pills or powders you can mix into water or other beverages. The best diet pills are independently tested for safety and may have a coated capsule to prevent unwanted side effects like burping, indigestion and constipation.
Side effects
Some weight loss ingredients are known to cause unwanted side effects. For example, raspberry ketones may cause raspberry-smelling burps. Conjugated linoleic acid (CLA) can cause various digestive side effects and may be linked to long-term harmful effects like fatty liver and increased inflammation.
Over the Counter vs. Prescription Weight Loss Drugs
Over the counter (OTC) weight loss supplements are purchased online or in stores without a prescription. Weight loss medications require a doctor’s prescription. Prescription weight loss pills include drugs like orlistat and may have adverse side effects. Weight loss medication is typically only prescribed if you have a BMI over 30 or a medical condition related to your weight, like type 2 diabetes or high blood pressure.
Note that OTC weight loss supplements are often not regulated by the USDA and FDA, while prescription supplements are. Prescription supplements also contain regulated medications, which will not be found in OTC supplements. You can only get prescribed weight loss supplements with a doctor’s order, after medical examination, says Avena.
Supplements for Weight Loss FAQs
How do you speed up weight loss?
Our best advice: Instead of worrying about how to lose weight fast, concentrate on how to lose weight safely.
There are multiple ways to accelerate weight loss, but they’re not all healthy. Surgery is one option, but it comes with the increased risk of complications during and post-operation. Fasting is another way to lose weight fast, but may cause deficiencies in essential nutrients your body needs to stay healthy.
A healthy diet and regular exercise (caloric energy deficit) are proven methods of weight loss and, generally, the safest. A healthy diet and regular exercise have been shown to be superior methods of long-term weight management. In other words, they help prevent weight gain and maintain fat loss longer compared to rapid weight loss methods. They help get your body into fat burning mode and keep it there.
Related Post: Best Fat Burning Foods
What's a realistic weight loss goal per month?
The general consensus among trusted sources such as the National Institutes of Health and the Centers for Disease Control and Prevention is 1-2 pounds per week, which works out to 4-8 pounds per month. Why 4-8 pounds per month instead of something higher? Research suggests that gradual, steady weight loss at a reasonable rate increases your chances of keeping the weight off.
How can I boost my metabolism to lose weight?
Whether you have a speedy or slow metabolism is largely determined by your genes, so to some extent you're stuck with the metabolism you were born with. However, research suggests that you can give your metabolism a boost with physical activity like high-intensity interval training, along with drinking green tea and eating more protein. You can also try a weight loss supplement with ingredients that support a healthy metabolism, such as the aforementioned green tea.
Final Thought: Weight Loss Supplements Can Work, But Always Get Medical Input Before Trying Them
If you're considering taking a supplement to help you lose weight, don't limit yourself to browsing products and reading blogs. Talking with a doctor or a nutritionist is essential, not just because of your health but also for questions of effectiveness.
"It’s important to remember that supplements are not medicine, so they are not proven to work in many cases," Avena says. "Many brands do promote their supplement as a weight loss supplement if it contains ingredients that curb appetite, boost energy, and boost natural metabolic processes—for example, caffeine."
The advice from Avena and other medical professionals remains the same: Always consult your doctor before using a new supplement for weight loss.
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