Diet Pills Ingredients: Important Things To Know

When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Lately, diet pills have gained huge popularity among people who are struggling to lose weight. Although making a few positive diet and lifestyle changes remain the most sustainable way to lose weight. Notwithstanding, people are turning to weight loss pills to make their weight loss journey easier. 

Most of the supplements on the market today promise to boost fat burning, suppress appetite, and limit the absorption of fat in a bid to help you get your dream body. Some of them are prescription diet pills while some were gotten over the counter.

Examples of over-the-counter diet pills include Alli (orlistat), glucomannan, Hydroxycut, Garcinia Cambogia, and others. Although the manufacturers make bold claims about possible benefits. But the fact remains that only a few cases of research have been carried out to confirm the efficacy of some of these products for weight loss. So, it is best to consider real human reviews before spending money on any pill.                  

Not all diet pills work the same way. While some may help you lose some pounds, others may have serious side effects on you. Common side effects of diet pills include diarrhea, digestive problems, anxiety, and nausea, among others.

You may want to try out some dietary supplements if you need to jump-start your weight loss or you’re stuck in a weight-loss rut. But before you do that, it is advisable you check out the ingredients that make up the supplement.  

Active Popular Over-The-Counter Diet Pills Ingredients


Caffeine is one active ingredient you would likely find in almost all prescribed and over the counter diet pills. It’s the most commonly consumed psychoactive substance globally. Caffeine is naturally found in coffee, green tea, and dark chocolate.

Caffeine helps to boost metabolism. Studies have shown that caffeine can help increase metabolism by 3-11%. It can also help accelerate fat burning up to 29%.

Green Coffee Bean Extract

Green coffee bean extract is known to contain two substances that can promote weight loss: caffeine and chlorogenic acid. Caffeine can help in burning unwanted fat in the body. Chlorogenic acid on the other hand can help slow the digestion of carbs in the gut.

Many research results have indicated that green coffee bean extract can help humans to lose weight. The substance can also help lower the risk of high blood sugar as well as high blood pressure.

Green Tea Extract

This is another common ingredient in many weight loss pills and dietary supplements on the market. Green tea extract can aid fat burning by increasing the activity of norepinephrine – a fat burning hormone. Many studies have shown that green tea extract can help fat loss especially around the belly.

Garcinia Cambogia Extract

Garcinia cambogia is a fruit that contains hydroxycitric acid. This ingredient is believed to help promote weight loss. This substance works by preventing a fat-producing enzyme called citric acid lyase. Meanwhile, there’s not much evidence on the ground on the effectiveness of the extract in long term clinical trials.


Pyruvate is a body-producing substance that’s thought to help in breaking down sugar. It’s also available over the counter as a dietary supplement with a promise to support weight loss. Pyruvate can significantly help break down fat and boost metabolism. Meanwhile, it should be noted that existing studies on the effectiveness of this ingredient are quite weak.

Ingredients to avoid in diet pills


Sibutramine is a powerful stimulant that can be found in some diet pills. This isn’t what you want to throw into your stomach. Sibutramine has been found to increase the risk of heart attacks, arrhythmias or stroke. It was removed from the market in 2010.


This substance is another harmful stimulant that has been banned in the United States. Fenproporex can cause heart arrhythmias and even sudden death.

Bitter Orange/Synephrine 

Bitter orange contains a chemical called synephrine. This chemical is similar to ephedra and can potentially increase heart rate, headache, insomnia, and high blood pressure. Some diet pill makers use it as part of their ingredients. So, you should watch out.


The Food and Drug Administration (FDA) has once declared Phenolphthalein as unsafe. Yet, some weight loss pills contain this same substance. Next time you’re shopping for a diet pill, make sure it doesn’t contain this unhealthy ingredient. 


Ephedra typically contains ephedrine and pseudoephedrine. These chemicals affect the nervous system and can result in high blood pressure. Irregular heart rhythm, heart attack and stroke can also be attributed to this substance.

The safest and most effective way to lose weight is through a balanced diet, taking in the right portion, and exercising. However, if you must use a diet pill, try to involve your healthcare provider in your weight loss plan. They can guide you on the appropriate pill that suits your health condition.