Appetite suppressants – commonly called diet pills – are a type of weight-loss drug that works on the brain signals and hormones to suppress appetite. It affects the brain’s urge to eat, controls hunger pangs, and makes you feel full faster after eating less food. As a result, you take in fewer calories and lose weight.
Appetite suppressants suppress or satisfy hunger by tricking the brain into believing that your stomach is full. It can do this by triggering a hormone response that interrupts brain signals telling the body it’s time to eat. It’s a ruse, but the strategy works.
The term “appetite suppressants” is generally used to refer to prescription medications. Still, it is also used by some herbal and natural diet pill manufacturers to describe their plant-based, non-prescription products that aim to curb hunger.
Prescription weight loss medications are usually prescribed to people with a body mass index (BMI) of at least 30 and those with conditions associated with excess body weight, such as heart disease, type 2 diabetes, and obstructive sleep apnea.
Do They Work?
Appetite suppressants work in many ways. Some make your body feel less hungry or full sooner, while others make it hard for the body to absorb dietary fat. However, they are not a replacement for certain lifestyle changes to achieve weight loss.
A systematic and clinical review of the long-term use of medications to treat obesity revealed that the drugs resulted in greater average weight loss than placebo when combined with lifestyle changes. On average, people who combine appetite suppressants with healthy lifestyle changes lose around 3-9 percent of their starting weight within 12 months. This reduction is a great start for people considering weight loss.
A person who started at 200 pounds would have a good chance of losing at least 10 pounds with the help of these medications. Some people lose more weight, while some lose less.
Appetite suppressants may help some people lose weight, but they do not work for everyone. Others still struggle to lose much more weight because medication alone doesn’t drive weight loss. Some only maintain their weight. Plus, the amount of food you eat is only one factor in weight loss. You still need to make conscious food choices, even if you may not feel hungry as you used to be. If you’re still picking fast food and junk food every time you eat, you won’t likely see weight loss.
Other daily lifestyle changes are necessary alongside taking appetite suppressants to experience weight loss. Besides choosing a healthier diet, developing an exercise routine can also help you burn excess calories and prevent you from eating out of boredom. Research has also shown that appetite can act as a natural appetite suppressant.
Also, appetite suppressants do not target mindless eating, emotional eating, and sedentary behavior, all of which are usually associated with being overweight and obese.
What are the Different Appetite Suppressants?
There are prescription and over-the-counter (OTC) appetite suppressants available in the market. Before buying OTC diet pills, consult your doctor.
Prescription Appetite Suppressants
These are some of the prescription diet pills approved by the US Food and Drug Administration (FDA).
1. Naltrexone-Bupropion
Brand names: Contrave, Mysimba
Contrave is an extended-release combination of two medications: naltrexone hydrochloride and bupropion hydrochloride. It targets the central nervous system to reduce appetite and curb cravings. It affects the reward system in the brain, so eating foods that would usually make you feel good will no longer do.
2. Phentermine
Brand names: Adipex-p, Suprenza, Lomaira, Ionamine, Sentis, Pro-Fast, Duromine, and Metermine
Phentermine is one of the oldest medications prescribed for weight loss in people with obesity. It’s a stimulant that makes you feel less hungry.
3. Phentermine/Topiramate
Brand name: Qsymia
This drug is an extended-release capsule that suppresses appetite and, as a result, reduces your food intake. It is prescribed along with a reduced-calorie diet and exercise plan.
4. Liraglutide
Brand names: Saxenda, Victoza
Liraglutide is an injectable medicine that acts on a hormone in the gut to dampen hunger, helping people to feel sooner so that they will eat less. It’s often prescribed as part of treatment for weight-related medical conditions like diabetes, high blood pressure, and high cholesterol.
5. Semaglutide
Brand names: Wegovy, Ozempic
Wegovy is a weekly injectable, an anti-diabetic drug used for treating type 2 diabetes and long-term weight management.
6. Diethylpropion
Brand names: Tenuate, Tepanil, Nobesine
Diethylpropion is a stimulant medication that targets the brain to suppress the appetite, which can lead to weight loss. It’s recommended for short-term management of obesity, along with lifestyle and dietary changes.
7. Phendimetrazine
Brand names: Prelu-2, Bontril, Adipost, Appecon, Melfiat, Obezine, Statobex, Anorex-SR, Plegine, Phendiet
Phendimetrazine is a stimulant drug used as an appetite suppressant. It’s very similar to phentermine, but phendimetrazine has a shorter half-life, meaning it can only be taken for a shorter duration than phentermine. Because of this, It can be taken up to three times daily when needed, whereas phentermine cannot.
Natural Appetite Suppressants
Meanwhile, there are some products available in health food stores, pharmacies, and vitamin shops that claim to be natural appetite suppressants. These supplements are not reviewed, tested, or approved for safety and effectiveness by the FDA – they are only regulated. If you are considering taking herbal or natural supplements to curb hunger, be sure to be informed before buying one, as some can be expensive and may not be as effective as you’d hoped.
1. Glucomannan
Extracted from the root of the konjac plant, glucomannan is filled with soluble fiber, which can help increase satiety and prolong the time it takes for food to leave the stomach. It can absorb 50 times its weight in water, filling up your stomach and making you feel full.
2. Garcinia cambogia
A fruit tree naturally growing in South Asia, Africa, and Polynesian Islands – Garcinia Cambogia contains high levels of hydroxycitric acid (HCA), which is thought to decrease appetite by suppressing food intake. However, evidence of effects is relatively minor.
3. Green tea extract
You probably already know that if you want tea for weight loss, go for green tea. The caffeine and catechins in green tea are both associated with weight loss. Also, drinking more liquids can help you lose weight, but it won’t do the heavy lifting. It’s best to drink a cup of tea or two a day, but skip pills and supplements that claim to contain it.
4. Fenugreek
Fenugreek is a Mediterranean herb whose seeds smell and taste like maple syrup. The ground-up fenugreek seeds and extracts are used in cooking, spice mixes, medicines, and even cosmetic products.
These seeds are rich in fiber and can act as a natural appetite suppressant by prolonging satiety. A study revealed that drinking fenugreek tea can lead to a higher feeling of fullness in women who are overweight.
5. Gymnema Sylvestre
Gymnema Sylvestre is an herb that is most known for its anti-diabetic properties. Its active compounds were shown to block the sweetness of foods, which can help decrease sugar cravings. This herbal supplement can help you eat fewer sugary foods, which will help your weight loss efforts.
What are the Risks of Using Appetite Suppressants?
Appetite suppressants can be beneficial when prescribed to a dieting patient, but it can be unsafe for some people to take them, and that’s why they must be taken with a doctor’s direction or consent.
Before taking any appetite suppressant – whether prescription or over-the-counter – discuss with your physician any underlying medical diagnoses, current medications, previous medical emergencies, and other concerns that might have an adverse effect on the suppressant. Before implementing any weight loss plan, discuss it with your doctor, as they may have a piece of advice regarding your weight loss regimen as it relates to your health history.
As with any medication, appetite suppressants may also cause side effects, including dizziness, nervousness, insomnia, dry mouth, increased blood pressure and heart rate, raised pulse, and digestive problems like nausea, diarrhea, constipation, and stomach upset.
Side effects are usually mild. Rarely, appetite suppressants also cause liver damage. Inform your healthcare provider if you notice some signs of liver disease like jaundice.
Appetite suppressants may also interact with other medications, including anti-anxiety drugs and antidepressants. Some appetite suppressants may increase the risk of suicidal thoughts or interact poorly in those people with depression or other severe mental health conditions.
These kinds of medications are also unsafe for pregnant or breastfeeding women. Do not take appetite suppressants if you have liver disease, glaucoma, heart disease, and hyperthyroidism.
Some experts believe that the risks are not worth it. In animal studies, one appetite suppressant, liraglutide, has caused thyroid cancer. However, it’s not known if it causes the same effect in humans. Another drug, lorcaserin, was requested by the FDA to be removed from the market due to an increased incidence of cancer in people taking it. If you decide to take appetite suppressants, tell your doctor if you encounter any side effects