Five Popular Appetite Suppressants Compared

Closeup of doctor checking patient daily report checklist

“You can’t outrun your fork” has become a cliche in the weight loss world. And for good reason. There’s only one thing absolutely required to lose weight: maintaining a net calorie deficit. You must burn more calories than you take in. The problem with using exercise to create that deficit is that even if you go balls-to-the-wall on physical activity you’ll only burn 30% more calories than you would laying on the couch -- at most. If you go extremely hard for an entire hour with no breaks you’ll burn fewer calories you’ll find in a Starbucks muffin.

Even worse? If you’re not watching what you’ll eat, exercising will amp up your appetite, causing you to eat more to compensate for those lost calories.

Here’s the bottom line: You can absolutely lose weight without exercise. You absolutely cannot lose weight without restricting calorie intake.

So how do you actually eat less when your biology and savvy marketers are doing everything in their power to get you to maintain or gain? The first step is to get an accurate picture of how much you’re currently eating. The vast majority of people severely underestimate how many calories are in their food and the average person underestimates how many calories they consume by 30%.


Personally, I’m a fan of obsessively tracking my calories with MyFitnessPal, a freemium app powered by Under Armour. It’s got a HUGE database of foods. Plus it gives you a breakdown of your nutrient intake. And if you give it your weight data, either by connecting your smart scale or manually inputting your weight daily, it’ll tell you at the end of each day how long it will take you to reach your goals if you ate that way every day.

Once you know how much you are, and should be, eating, it’s time to make a calorie deficit more tolerable. If you want to maintain a deficit long enough to lose the weight you want to lose it’s going to be physically and mentally challenging. Your body absolutely hates change, and not getting enough calories to maintain your weight is a change your body particularly hates. You’re going to feel bad things. Depending on what you’ve been eating and your unique physiology you might feel cramps, fatigue, irritability, cravings, etc. You need to mentally prepare yourself for this and know what you’re going to do when the bad feelings come, other than cave.

Here’s where a good appetite suppressant can help. It’s important to keep your expectations in check in order to maintain your motivation. There’s no appetite suppressant in existence (yet) that’s going to make weight loss easy. The best you can hope for is something that makes eating less than you’re burning a little more bearable.

Below I’ve compared five popular appetite suppressing supplements based on their type, active ingredients, pros, cons, and price. I’ve listed them in no particular order.

1. Skinny Bird

  • Format: Pill

  • Active ingredients: 5-HTP, Caralluma Fimbriata, Green Tea Extract, Chromium

  • Category: stimulant, serotonin


Skinny Bird is a pill you take with meals, up to three times daily. It contains an appetite-suppressing cactus called Caralluma as well as Chromium, a mineral thought to help regulate blood sugar. It’s also got Green Tea Extract, which contains caffeine and acts as a stimulant. And it impacts serotonin levels with 5-HTP. It’s gluten-free as well, so that’s nice.

One thing I’ll say for Skinny Bird is that it’s got some pretty powerful chemicals in it. Which means that it’s unlikely to do nothing, a suspicion confirmed by many Amazon reviewers. Very few reviewers complained about Skinny Bird being ineffective. Many people were very happy with it. Those who are unhappy, however, were very unhappy, complaining of stomachaches and nausea. Which, while unpleasant, will definitely put a damper on your enthusiasm for eating. A few people experienced vomiting, lightheadedness, headaches, and tremors. These are powerful, understudied chemicals, so take that into consideration. Also don’t take it with dinner if you’re sensitive to caffeine and want to be able to sleep.

Price: ~$32

2. Thermo Burn Extreme Weight Loss

  • Format: Pill

  • Active ingredients: Green Tea Extract, Green Coffee Bean, Caffeine Anhydrous, Cellulose, Raspberry Ketone, Garcinia Cambogia, Acai Berries, Mango

  • Category: stimulant


Thermo Burn Extreme Weight Loss is basically fancy caffeine. It’s duded up with some fiber and likely safe (but unproven to work) plants. But at the end of the day, it’s probably not going to do much for you beyond what coffee or tea would do to suppress your appetite. This is borne out in the Amazon reviews, which include few complaints of side effects but many complaints about the product not doing much. On the plus side, if you tolerate caffeine well it seems like a pretty innocuous thing to try. And it’s about a third cheaper than Skinny Bird.

Price: ~$17

3. Soylent Bridge

  • Format: Shake

  • Active ingredients: protein

  • Category: protein, meal replacement


Eating more protein is a great way to feel fuller on fewer calories. Plus it helps fuel muscle growth, and gaining muscle is one of the only ways to raise your resting metabolic rate. Nutritionists pretty much all agree that it’s best to get your protein from food. But sometimes that’s not possible, or convenient. So shakes can be a fast, easy way to get more protein into your diet.

Soylent Bridge is a lower-calorie version of the meal-replacement shake. The taste isn’t great or terrible, according to reviews on reddit and YouTube. It’s mostly just watery.

Price: ~$25

4. Pure Protein Shake

  • Format: Shake

  • Active ingredients: protein

  • Category: protein, meal replacement


This is my personal favorite among protein shakes. It’s got way more protein for the calories than Soylent Bridge, 170 calories for 35g of protein vs 180 calories for 15g of protein. Plus, the Frosty Chocolate flavor tastes genuinely great, in my opinion. Especially after a few hours, at least, in the fridge. Don’t freeze them though, it makes the texture weird after they thaw. Amazon reviewers mostly agreed, though taste is subjective and some hate it. One word of warning: For some reason this makes your breath smell quite bad. Not sure if that’s a problem with all protein shakes. But have some gum on hand for afterward. Also apparently there’s a good amount of sodium in these, if that’s something you’re watching. Also both shakes contain sucralose.

Price: ~$30

5. Atkins bars

Format: Bar

Active ingredients: Protein

Category: Protein, meal replacement


I’d say the main advantage Atkins bars have over the shakes is that they’re as healthy but they’re lighter and smaller, making them slightly more convenient. Plus, I don’t know about you, but I find it more satisfying to chew my calories rather than drink them.

They’ve also got more fiber than the shakes, which is great not just for suppressing your appetite but also is an important prebiotic. Amazon reviewers have few complaints. Most really like the taste.

Price: ~$20



You’ll probably get the most benefit from trying one pill along with one meal replacement. I wouldn’t double up on either. Taking two different kinds of pills increases the chances of ingesting unsafe amounts of caffeine, other stimulants, or liver-taxing chemicals. Eating two different kinds of meal replacements increases your likelihood of either gaining weight if you’re not reducing your real food intake or missing out on important nutrients if you are. Most of your calories should come from whole foods if you want to stay healthy.

Which pill and meal replacement you choose comes down to your risk tolerance, personal tastes, and budget. If you’d rather take a risk on unpleasant side effects than risk wasting your money, Skinny Bird is a good bet. However, if you’re wary of powerful, understudied chemicals, Thermo Burn Extreme Weight Loss is a good place to start. If you enjoy drinking shakes and want to save a little money, Soylent Bridge is a little less expensive, per serving, than Pure Protein shakes. But if you want the most protein for the fewest calories, go with Pure Protein. Atkins is a great choice if you like to chew your food.

Want to try these products at discounts of at least 20% and don’t mind connecting your data to do so? Download Biomarker today.

Cathy Reisenwitz