Do Weight Loss Pills Work? The Truth About Weight Loss Supplements

Discover the facts about weight loss pills, how they fit into a fitness regimen, potential side effects and how they can support your weight loss journey.

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Weight loss is one of the most common fitness goals. While nothing beats good old-fashioned hard work and a healthy diet, many people are looking toward supplements and asking, “Do weight loss pills work?”

Supplements are just that: supplementary. They should never be your first line of defense for weight loss.

With that said, when combined with a healthy nutrition program and regular resistance training, the best supplements for weight loss may support your goals of getting lean.

But are all weight loss pills created the same? Not even close.

Let’s look closer at weight loss pills, breaking down how they work, proven ingredients and side effects. We’ll also discuss whether you should take weight loss supplements or chat with your doctor about weight loss prescription drugs.

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.

How Do Weight Loss Pills Work?

“Weight loss [pills] are products designed to aid in weight management by supporting fat burning, reducing appetite or enhancing metabolism,” says Mary Sabat, MS, RDN, LD.

When weight loss pills have certain ingredients and are combined with the best diet for weight loss and strength training, they may contribute to weight loss by doing four things:

• Reducing appetite: Weight loss ingredients like caffeine have been shown to suppress appetite, which helps you decrease your overall caloric intake throughout the day. The fewer calories you eat (within a healthy range), the more you support weight loss. (1)
• Blocking fat absorption: Certain ingredients like garcinia cambogia may help by preventing or delaying the body from absorbing fat from the food you eat. (2)
• Boosting metabolic response: Green tea and a few other weight loss ingredients may help boost your metabolic rate, resulting in your body burning more calories than it normally would, even at rest. (3)
• Increasing fat oxidation: Some weight loss pills such as Capsimax (cayenne pepper extract) use capsaicinoids to potentially boost the body's ability to burn fat, especially during exercise. (4) This may help you get more from your workout sessions.

Keep in mind that not all weight loss supplements will provide these benefits.

“The weight loss supplement industry is not tightly regulated,” says Aleksander Saks, NSCA, CSCS. “There is limited scientific evidence to support the claims made by many [weight loss] products. It's important to be skeptical of exaggerated claims and always consult with healthcare professionals before starting any weight loss regimen.”

What Ingredients Are in Weight Loss Pills?

The ingredients in a weight loss pill can make or break the supplement.

Here are some of the most popular and well-researched weight loss ingredients to look for when purchasing weight loss pills.

Capsimax powder

Studies suggest that the potent and easily absorbed capsaicinoids in Capsimax powder may help with weight loss. Capsaicinoids work by boosting your body's ability to produce heat (thermogenesis) and support the natural fat-burning process. (5)

Chromium picolinate

Chromium picolinate is a mineral that enhances insulin function and could potentially improve metabolism, reduce cravings and promote fat loss. (6) One study found that those who consumed chromium picolinate supplements lost significantly more weight than those who took a placebo. (7)

Caffeine

Aside from the cognitive benefits, caffeine can also support weight loss in a few ways. It may suppress appetite, boost fat burning and give you more energy. (8)

L-Carnitine

L-Carnitine is an amino acid derivative that aids weight loss by transporting fats into cells to be used for energy, preventing new fat storage. (9) This boosts fat metabolism and, when combined with diet and exercise, can help with weight loss. L-Carnitine may also help reduce hunger and fatigue, making it easier to stick to a diet or exercise routine. (10)

Guarana

It's thought that guarana, due to its caffeine content, boosts the functioning of brown adipose tissue or brown fat. The thermogenic properties of guarana could potentially activate brown fat, leading to higher energy use and assisting in weight control. (11)

Green tea extract

One study looked at whether green tea extract (GTE) could help burn fat after exercise. The researchers found that people who took GTE, compared to those who didn't, burned more fat both during rest and after a short exercise session. (12)

Are There Any Side Effects of Taking Weight Loss Pills?

Depending on what type of weight loss pill you take, there is a chance for the following side effects (13):

• Digestive issues: Weight loss pills that block fat absorption may cause unpleasant gastrointestinal side effects, especially laxatives or supplements using guar gum. These may include bloating, gas and even diarrhea.
• Increased heart rate and blood pressure: Some weight loss pills, especially those that boost metabolism, often contain stimulants like caffeine. These can cause an increased heart rate and blood pressure, posing a potential risk to individuals with heart conditions.
• Mood changes and insomnia: Pills containing stimulants can also lead to sleep disturbances and mood swings.

With these side effects in mind, are weight loss pills worth taking?

“The answer isn't black and white,” says Kelvin Fernandez, MD. “It's a conversation that needs to take place between a healthcare provider and the person considering this path. It’s crucial to consider the individual's health history, potential benefits, possible side effects and overall impact on their lifestyle.”

Who Can and Cannot Take Weight Loss Pills?

Weight loss pills might sound like an easy solution to shed pounds, but they're not for everyone. If you’re a generally healthy adult with no serious pre-existing conditions and have a Body Mass Index (BMI) of 25 or above, then you may be able to consider using weight loss pills. (14) However it’s important to note you should speak with your doctor before taking any supplement, and that BMI is not an accurate marker of health or body composition. 

Weight loss pills aren't magic, and you’ll need to pair them with a healthy diet and exercise program. You cannot rely solely on weight loss supplements for results.

That said, certain groups should typically avoid weight loss pills, including:

• Pregnant or nursing women: Weight loss pills can potentially impact fetal development and nursing infants. (15)
• Individuals with certain medical conditions: People with heart disease, high blood pressure, liver disease or other specific conditions may be advised against using weight loss pills due to potential health risks.
• Individuals with sensitivity to stimulants: Most weight loss supplements contain stimulants like caffeine and yohimbine. If you have a sensitivity to stimulants, it’s not recommended to take weight loss pills as this can affect your mood, mental state, sleep, etc.
• Teens and children: Weight loss pills are not recommended for younger individuals because their bodies are still developing. (16)
• Individuals with eating disorders: Those struggling with eating disorders may face increased risks and should typically avoid these supplements.

It's essential to consult a healthcare provider before starting a weight loss pill regimen. They can provide the necessary guidance considering your overall health, weight loss goals and potential risks.

Weight Loss Pills vs. Prescription Weight Loss Drugs

When it comes to burning fat and losing weight, both over-the-counter weight loss pills and prescription weight loss drugs have their place. But they're not the same thing.

While over-the-counter weight loss pills can be helpful, they aren't regulated by the FDA (Food and Drug Administration), which means their effects are often less predictable, potentially less effective and sometimes even harmful when compared to prescription weight loss drugs.

Prescription drugs tend to be more efficacious because they are more strictly regulated and have accompanying studies.

These medications work in various ways, depending on the specific drug. Some work by suppressing your appetite; others may block fat absorption in your body, reduce cravings or increase feelings of satiety.

Some common prescription weight loss drugs include orlistat (Xenical), phentermine-topiramate (Qsymia), naltrexone-bupropion (Contrave), liraglutide (Saxenda) and semaglutide (Wegovy).

They are typically better suited for individuals who are:

• Suffering from complications due to their weight (e.g., joint pain, high blood pressure, etc.)
• Have not been able to achieve their weight loss goals through diet and exercise alone

Whether you take weight loss pills or prescription weight loss drugs, it’s important to remember two things:

1. These should be used as tools to supplement a healthy lifestyle, not replace it
2. You should always speak with your doctor before trying either weight loss pills or prescription drugs

Our Top Product Recommendations

• PhenQ
• Swolverine Therm
• Transparent Labs Recomp
• LeanBean

PhenQ

PhenQ

PhenQ is an all-natural weight control solution designed to target five essential aspects of metabolic well-being, assisting in the reduction of surplus fat, suppressing hunger pangs and promoting innate energy levels.

It has weight loss ingredients, including many mentioned above, that may provide the following benefits:

• May help promote fat burning: PhenQ contains a potent mix of alpha lipoic acid, cysteine base, magnesium and Capsimax powder. (5,17) Together, these ingredients have been shown to help spark thermogenesis and lead to weight reduction, appetite control and maintaining energy levels throughout the day.
• May help curb food cravings: PhenQ has a natural blend of chromium picolinate, nopal cactus and caffeine. (6,8) These ingredients work together to reduce pesky cravings while promoting a feeling of fullness.
• May help prevent fat storage: The capsaicinoids present in Capsimax powder actively work to prevent the build-up of surplus fat cells and obstruct the creation of new ones. (5)
• May boost energy levels: Since PhenQ contains natural stimulants like caffeine and Capsimax, you’ll notice a boost in your day-to-day energy levels. (5,8)
• May promote positive mood: L-carnitine isn’t just a great way to promote healthy weight management, it can also support a positive mood as you go through your weight loss journey. (10)

Swolverine Therm

Swolverine

Swolverine's Therm is another natural thermogenic supplement designed to kickstart your metabolism, so you can potentially burn more calories at rest.

This weight loss supplement contains 20 handpicked active weight loss ingredients. Let's focus on the top three ingredients in this blend:

• Green tea leaf: Green tea for weight loss isn't just a tasty drink; it's also a great way to support your weight loss. Its natural caffeine content and powerful antioxidants can help enhance your body's metabolic efficiency, aiding in weight loss and weight management. (12)
• Yerba mate: Another type of delicious drink from South America, yerba mate can help to control your appetite by helping to curb your cravings. It may also help by boosting your daily energy levels. (18)
• Garcinia cambogia: This tropical fruit extract may increase your basal metabolic rate, reduce fat mass and lower lipid and blood glucose levels. (19)

Whether you're already well into your fitness journey or just getting started, Swolverine Therm could be the supplementary boost you've been looking for.

Transparent Labs Recomp

Transparent Labs

Transparent Labs Recomp is a potent weight management supplement designed to help you achieve your goals. It features five key ingredients studied for their weight loss benefits:

• Green tea leaf extract: Green tea extract is a powerhouse of antioxidants, especially EGCG, which has been shown to enhance the body's metabolic rate, helping burn calories more efficiently. (20)
• Forslean: Forskolin is a compound that may help stimulate the release of stored fat from cells. This could potentially aid in weight loss when paired with a calorie deficit. (21)
• Natural caffeine: Caffeine from green coffee beans not only boosts energy levels but may also help kickstart your metabolism and increase fat burning, especially during exercise. (8)
• L-Theanine: This amino acid commonly found in tea leaves may help reduce stress and promote relaxation without causing drowsiness. (22)
• Capsimax (red pepper (fruit) extract): Capsimax harnesses the heat of red peppers to help boost metabolism and increase the number of calories your body burns, potentially contributing to weight loss. (5)

This unique blend in Transparent Labs Recomp helps support your weight loss journey by potentially enhancing your metabolism, burning fat and reducing cravings.

Related Post: The Best Thermogenic Fat Burners to Try for Fat Loss

LeanBean

LeanBean

Leanbean is a fat burner specifically designed for women, featuring an ingredient known as glucomannan, which comes from the natural Konjac plant fiber. This special fiber acts like a sponge in your stomach. When it meets with water, it can expand up to 50 times its size, creating a sensation of being full. (23)

Leanbean contains 40 milligrams of green coffee, which is packed with something called chlorogenic acid and a little caffeine. Chlorogenic acid may aid in weight loss by decreasing sudden food cravings, speeding up your calorie-burning rate and decreasing the amount of fat your body takes in from what you eat. (24)

Probably one of the most notable benefits of Leanbean is that it is free of any extreme stimulants. Green coffee has some naturally occurring caffeine, but the amount is trivial compared to other weight loss pills that contain 200 milligrams or more per serving.

Final Thoughts: Are Weight Loss Pills Right for You?

The foundation of a healthy weight loss plan has two giant pillars: smart nutrition and consistent exercise. If these pillars aren’t in place, weight loss pills won’t be able to do much for you. Sure, you might notice short-term benefits like increased energy or even water weight loss, but when you stop taking the weight loss supplements, you’ll be right back where you started.

Focus on building the habit of nutrition-focused meal prep and participating in a weekly workout plan—a plan that is a combination of resistance training and cardiovascular exercise. Once you have a strong fitness foundation, then you can consider building upon it with weight loss supplements.

If you’ve been down the road of exercise and nutrition with very little success, talk to your doctor about prescription weight loss drugs. You’ll still need to focus on building healthy habits, but the prescription could help to kickstart your weight loss. And seeing results could be a great motivator to continue to work hard to achieve your fitness goals.

Prices are accurate and items in stock as of publish time.

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