Side Effects of Thermogenic Pills

Thermogenic pills are often advertised and sold as a way to increase metabolism and lose weight.
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Thermogenic pills are often advertised and sold as a way to increase metabolism and lose weight. While research exists on the effectiveness of some of the ingredients, many come with adverse side effects that make them unsafe for certain at-risk populations as well as some healthy adults.


Common Thermogenic Ingredients

Since the focus of thermogenic pills is to increase weight loss, some will include ingredients that claim to increase urination or bowel movements, stimulate the central nervous system or increase serotonin levels, according to the Cleveland Clinic. While these statements are broad and not necessarily specific to all ingredients, it's important to look at some of the more common ingredients in thermogenic pills. These include:


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  • Caffeine
  • Green tea
  • Capsaicin
  • Garcinia cambogia
  • Yohimbe
  • Bitter orange

Since the market is saturated with options, it can be challenging for consumers to know if a product is safe and if it really does what it claims. Reading the reviews can help you get a better idea of what other users have to say, but you should also read the supplement label and research each ingredient before taking the product. For example, the Sculpt Nation Burn online reviews are very limited, but the Burn XT has over 8,000 reviews on Amazon that range from "should be banned" to "added energy and boost to weight loss."


To learn more about individual ingredients, consider talking with a registered dietitian, pharmacist or check out the Office of Dietary Supplements and the National Center for Complementary Integrative Health, which are both from the U.S. Department of Health and Human Services. Additionally, it's a good idea to talk with your doctor about any supplement you want to take, especially if you have an existing health issue or take any medications.

Read more: How Do Thermogenic Fat Burners Work?


Thermogenic Side Effects

Depending on the ingredients in a thermogenic, side effects can range from mild to severe, and in rare situations, even death. Some of the more common side effects include:

  • Restlessness
  • Trouble sleeping, insomnia
  • Headaches
  • Diarrhea
  • Upset stomach
  • Elevated heart rate
  • Elevated blood pressure
  • Feelings of anxiety or panic
  • Agitation


All ingredients in a thermogenic come with some risk. That said, some have more reported adverse effects than others.

Many thermogenic, weight loss and energy products include caffeine as a primary ingredient. While a dose of caffeine may have a minor impact on weight loss, the Mayo Clinic points out that it will not result in significant or permanent weight loss. Some people may experience adverse side effects such as insomnia, jitters, anxiousness, fast heart rate, headache and nausea from consuming too much caffeine, according to the U.S. Food and Drug Administration (FDA). The maximum recommended amount of caffeine is 400 milligrams per day, which means, if you drink caffeinated beverages and decide to take a thermogenic with caffeine, you could quickly reach, and possibly exceed the maximum recommendation.



Bitter orange, which contains a compound called synephrine, is often included in thermogenic products because it has chemical properties and actions that are similar to ephedra, according to the Mayo Clinic. Ephedra or ma-huang, is a herbal supplement banned by the FDA. While the National Center for Complementary and Integrative Health says bitter orange may be unsafe since there are reports of healthy people experiencing adverse side effects such as fainting, heart attack and stroke after taking bitter orange, they also point out that the evidence regarding negative effects on the heart are inconclusive. Other reported adverse effects include chest pain, anxiety, headache and increase in blood pressure and heart rate.


Yohimbine, which is an alkaloid from a West African evergreen tree, is often promoted for bodybuilding and weight loss. Several reports of an increase in blood pressure, headaches, anxiety, agitation, tachycardia and cardiac failure, have been reported from taking higher doses. The ODS points out that no safe dose has been established.

Read more: The 7 Principles of Fat Loss


Tips for Safe Weight Loss

It's tempting to reach for a pill when you want to lose weight. However, most experts will tell you that diet combined with exercise is the safest and most effective way to boost your health and lose a few pounds. It's also the best way to maintain long-term weight loss, according to Johns Hopkins Medicine.

To lose weight and keep it off, the Academy of Nutrition and Dietetics recommends skipping on any diet that claims rapid weight loss, doesn't include exercise as part of the plan, requires you to follow a rigid menu or eliminates entire food groups. While these diets may initially result in quick weight loss, it's also likely that you may regain some of the pounds if you go back to your old eating habits.

Sticking to a diet full of fruits, vegetables, lean protein, complex carbohydrates and healthy fats, is a great place to start. Also, including some form of physical activity at least five days a week can help burn calories and improve your overall health. The Physical Activity Guidelines for Americans recommends 150 minutes a week of moderate-intensity cardio exercise each week, as well as a minimum of two days a week of resistance training focusing on the major muscle groups.




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