Thermogenic and weight-loss supplements can help you manage weight, lose fat, and get a boost of energy, but how do you decide which to use? While fat burners can offer many benefits, some do have side effects and interactions with supplements that can make it difficult to achieve your goals.

Finding the right formula will depend on your weight-loss goals and your current nutrition or supplement program. Some of the leading thermogenic formulas are:

Cytodyne Xenadrine
In its Xenadrine products, Cytodyne uses a proprietary Thermodyne Complex made with green-tea extract, L-tyrosine, caffeine, guarana, and other ingredients to increase metabolism. Two capsules before breakfast and two capsules in mid-afternoon is the standard dose; each dose contains the caffeine found in one cup of coffee (200 milligrams).

Optimum Nutrition Mega Fat Burners
Mega Fat Burners from Optimum Nutrition contains a combination of L-carnitine, choline, and inositol to support fat breakdown and metabolization. It also contains Garcinia cambogia for an energy boost, along with chromium picolinate and calcium. Two tablets per day is the recommended dose.

Optimum Nutrition Thermo-Cuts Extreme
Another Optimum Nutrition product, Thermo-Cuts Extreme, contains a blend of metabolic enhancers, including synephrine, alpha-lipoic acid, and extracts of green tea, guarana, and guggul. The recommended length of use is just eight weeks, with a serving size of two capsules.

MuscleTech Hydroxycut
Hydroxycut is a powerful thermogenic from MuscleTech that elevates norepinephrine in the body to stimulate weight loss. Key ingredients include green-tea extract, caffeine, white willow extract, and a proprietary Yohimbacore blend that’s meant to support mental focus and increase alertness.

EST Thermostat
EST’s Thermostat is a metabolic enhancer made with all-natural hoodia cactus. The powerful stimulant helps suppress the appetite, metabolize carbohydrates efficiently, and aid in water loss. Thermostat also contains caffeine for energy and increased alertness. Other key ingredients are niacin, vitamin C, cayenne pepper, and white kidney bean extract (for carbohydrate facilitation).

Neogenix Thermocharge
Thermocharge from Neogenix (formerly known as Nutragenx) is a powerful fat-burning solution designed to increase energy and improve mental focus. Among the most potent ingredients in this fat-loss supplement are synephrine, norsynephrine, tyramine, and hordenine. These can simulate the effects of ephedra, and suppress the appetite. The norsynephrine compounds are designed to prevent catabolism of the muscles, helping users burn fat while preserving hard-earned muscle through each workout.

Tread Carefully
Being aware of the normal effects of fat burners—along with potential side effects of the powerful compounds in each formula—can help you make the right choice. Many weight-loss supplement manufacturers outline the benefits but provide limited information on individual ingredients. It’s best to consult with a physician before beginning any extended weight-loss program.

Anyone who has a history of heart problems, diabetes, thyroid problems, or high blood pressure should take special care in taking a thermogenic supplement or weight-loss formula. Most of these are made with powerful compounds that can increase blood pressure, heart rate, and blood circulation.

No Miracle Cures
To see long-term results, no thermogenic product will do the job alone; you’ll still need to eat a balanced diet.

—Sabah Karimi