Green Tea, Capsaicin, and Ginger for Weight Loss Naturopathic Approaches Explained

In 2015, more than one in four adults had obesity in Canada, meaning their body mass index (BMI) was over 30. This rate is on the rise, and with it the risk of type 2 diabetes, high blood pressure, heart disease, stroke, arthritis, and cancer, all of which are associated with obesity.^[1] Although many individuals turn to exercise to kick-start their weight-loss program, diet plays the biggest part in shedding those excess pounds. Limiting caloric intake and focusing on whole unprocessed foods—such as vegetables, lean meats, healthy fats, and whole grains—is the number one treatment for obesity. Dietary changes account for up to 80% of weight-loss success, while physical activity accounts for 20% and mostly as a maintenance intervention long-term.

When it comes to weight loss, there always seems to be a “honeymoon” period were the weight comes off more easily, then a plateau is reached where it becomes harder to continue losing weight. These are the two phases of weight loss. The first phase is appropriately called the “weight-loss phase.” If you’ve ever tacked a new diet and exercise regime, you may have seen promising results in the first 6–8 weeks, lasting up to 6 months. This is because weight loss is most drastic in the beginning phases, as the decrease in caloric intake is greatest relative to your previous diet. Although rebounds are expected during this phase, the overall result is modest weight loss of 5–10% of your starting body weight. This may not be enough to meet your personal weight loss goals, but even a 10% body-weight loss has numerous health benefits such as reducing your risk of diabetes, stroke, and heart attack. The second phase is termed the “maintenance phase” and should last a lifetime. This is when lifestyle changes—such as portion control, a balanced whole-food diet, and regular exercise—should be maintained within healthy limits and integrated into daily routine.

Once diet and lifestyles changes have been optimized, supplements may be used to help support weight loss. Although no miracle pill exists for weight loss, herbs and supplements included, some research has shown modest benefit in using supplements conjunctively with caloric restriction. A recent study published in the Annals of Nutrition and Metabolism this past June tested a combination supplement of green-tea extract 125 mg, capsaicin 25 mg, and ginger 50 mg for weight loss. In the study, 50 overweight women were divided into two groups, one receiving the supplement combination twice a day, and the other receiving placebo for eight weeks. They noticed a statistically significant difference in weight loss between the two groups, with the test group losing roughly 2 kg more weight than the control group. They also noted improved glucose tolerance and increased glutathione levels.^[2] The latter is important, as it is a strong antioxidant and may play a role in cancer prevention. Previous studies have also tested these herbs individually with mixed results. Let’s take a look at each one individually.

Made from a type of leaf called Camellia sinensis, green tea contains caffeine and catechins, such as epigallocatechin gallate (EGCG), which are thought to have thermogenic effects in the body, favouring weight and body-fat loss. Numerous studies have been completed to test green tea’s effects on weight loss, and in 2014, a meta-analysis of 154 randomized controlled trials was published. It concluded a slight reduction in mean fat mass of 0.76% between the group receiving green tea and the control group after 12 weeks, but overall there was no significant difference in weight loss between both groups.^[3] This raises the question of the role of capsaicin and ginger as beneficial herbs for weight loss, since the research for green tea doesn’t support its use for weight loss.

Capsaicin is an active ingredient in plants belonging to the Capsicum genus, such as chili peppers. It interacts with sensory neurons, creating a burning sensation when it comes in contact with mucous membranes. As such, its culinary use is to add spice or “heat” to recipes. Some people may even experience pleasure and euphoria from ingesting it, due to the release of endorphins when sensory receptors are activated. Aside from making you smile and sweat while eating it, capsaicin can also be used medicinally as a topical analgesic, providing temporary pain relief for conditions such as arthritis, backaches, strains, and sprains.^[4]

Due to its thermogenic effect on the body and possible stimulation of fat metabolism, it has been studied as a supplement for weight loss. One trial followed 91 overweight adults for three months. All the participants followed a calorie-restricted diet for four weeks, i.e. the first phase of weight loss, and they all lost a similar amount of percent body weight. For the last eight weeks, they tried to maintain the weight they had lost. During this maintenance phase, half of them received 135 mg of capsaicin per day, and the other half received a placebo. At the end of the trial, there was no difference in amount of weight regained between the two groups, although fat oxidation was sustained in the treatment group.^[5] Another trial also looked at body-fat changes with capsaicin supplementation. In this second study, 80 overweight and obese adults also followed a low-calorie diet for four weeks, then either received capsaicin or placebo for eight weeks. The results demonstrated a slight decrease in body-fat mass in the treatment group versus the control group.^[6] Overall, capsaicin may support weight maintenance after a low-calorie diet, but more well-designed clinical trials are needed to confirm the results of these studies.

Ginger, aka Zingiber officinale, is beneficial for numerous health conditions such as irritable bowel syndrome, rosacea, vertigo, as well as nausea and vomiting in pregnancy. It may also help regulate blood glucose, which is beneficial in obesity. In 2016, a study looked at the effect of ginger on metabolic and clinical features of obesity in 80 women. The trial lasted 12 weeks, during which time the treatment group received 2 g of ginger powder per day and the control group received two 1‑gram tablets of corn starch. The study observed a statistically significant decrease in body mass index (BMI), serum insulin, and glucose sensitivity in the treatment group versus the group receiving corn starch. Overall, the researchers concluded that ginger may have a minor beneficial effect on weight loss and some metabolic features of obesity, such as blood sugar dysregulation, but given so few trials on ginger for weight loss these results are not definitive.^[7]

On the whole, green tea and capsaicin seem to be beneficial in supporting fat metabolism, which would help maintain weight loss, and ginger may also add the benefit of glucose regulation. This may explain the 2 kg difference in weight loss as well as improved glucose tolerance when supplementing all three herbs for weight loss. As with most nutritional supplements, their effects may be synergistic if used together, and less effective when used individually. As for the increased glutathione serum levels measured when using all three supplements for eight weeks, this measure was not tested in other studies, therefore knowing which herb may be responsible cannot be concluded at this time. Nonetheless, these were all relatively small studies, with less than 100 participants, therefore they are lacking power. More studies are needed in order to fully conclude the effects of green tea, capsaicin, and ginger as a combination supplement for weight loss. They may be beneficial if used as part of a complete weight-loss treatment plan including dietary and lifestyle changes.