So here it is: These are the top spices (and the occasional herb) to foster weight loss and boost your metabolism. All of course while making your meals more flavorful. Capsaicin is known to target the nervous system and has been shown to increase satiety and thermogenesis1 (which refers to your body’s ability to produce heat from burning calories), all of which affect weight loss. In one study of 24 people, researchers investigated the effects of 0.9 grams of red pepper (0.25% capsaicin) added to tomato juice for a spicy concoction and found a significant reduction in energy (or calories) and fat intake2 after consumption. Another study of 25 people wanted to see if there was a difference in thermogenesis after red pepper consumption3 between people who regularly consume spicy foods and people who don’t. This study did find that 0.9 grams of red pepper consumption enhanced thermogenesis in participants. This indicates that the body was producing more heat, and therefore burning more calories. Another interesting finding from this study was that these effects were even more amplified in people who didn’t regularly consume spicy foods. So if you don’t eat spicy foods now, consider this is your cue to start. A recent analysis of over 21 studies assessed curcumin’s influence on weight loss for 1,604 people with metabolic syndrome. Curcumin intake was associated with a significant reduction in BMI, weight, and waist circumference5. This analysis included studies where the amount of curcumin consumed varied between 70 and 2,400 milligrams per day, so there was no clear cut value for how much curcumin is needed to see the most benefit. A systematic review and meta-analysis published in 2019, evaluated 14 randomized controlled trials with a total of 473 participants, found that ginger supplementation significantly decreased body weight and waist to hip ratio as well as decreased insulin resistance8 (meaning, the body is better able to better control its blood sugar levels). In one small, randomized clinical trial, 88 women with overweight and obesity were assigned to either take three grams of cumin powder with a yogurt two times a day for three months or to eat the same amount of yogurt without cumin. The women in the cumin group had significant reductions in weight, BMI, waist circumference, and fat mass10 at the end of the study. Bonus: the cumin group has had improved cholesterol and triglyceride levels! These mechanisms prevent you from experiencing spikes and dips in your blood sugar levels, which can make you hungry. Cinnamon’s balancing of blood sugar act may be more prominent in people with diabetes or with insulin resistance13 (significantly reducing fasting blood glucose levels by 18 to 29%), but it can also be beneficial for people without those conditions. More research is needed on both ends before we can be sure. Generally speaking, one teaspoon of Cassia cinnamon per day is considered safe for adults according to European guidelines, and slightly higher amounts of Ceylon cinnamon can be tolerated. Search out Ceylon cinnamon to be on the safe side. A small study of 12 healthy men compared a high dose of fenugreek seed extract (1176 milligrams), and low dose (588 milligrams), and a placebo pill per day for two weeks. The high dose fenugreek extract significantly decreased the amount of fat the men were eating14 per day, leading to them consuming less calories overall. Lab and animal studies also indicate that piperine may positively influence body weight and other markers of health16. In one animal study17, rats fed a high fat diet with high blood lipid levels were either supplemented with piperine or an appetite supressor, while continuing eating a high fat diet. At the end, the piperine group had significant reductions in body weight, cholesterol, and triglyceride levels17, but there was surprisingly no change in the rats’ food intake. This suggests that piperine may promote weight loss without affecting appetite and without eating less food (and who doesn’t want that?). In one preclinical study, rats who were being fed a high fat diet that also received saffron extract supplementation had significantly decreased food intake19 compared to just eating the high fat diet alone. This may indicate that saffron can affect satiety or lower appetite, but since this study was done in animals, it’s difficult to correlate those measures. However, a clinical trial of 84 patients with coronary artery disease were randomized to either receive 30 milligrams of saffron in a water solution, 30 milligrams crocin (the main pigment in saffron), or a placebo. Patients in the saffron group had significantly decreases in BMI, waist circumference and fat mass20 compared to the crocin group. Saffron was also noted to be the most effective of the three groups in suppressing appetite and food intake, showing that, in this scenario, the spice as a whole has more benefits than the pigment alone. The short answer? Maybe. One study showed that rats fed a high fat diet with rosemary leaf extract had a significant reduction in weight and fat mass gain22 in about seven weeks. However, more research is needed before we can make that same conclusion in humans. There is no limit to the number of spices you can include in your diet in a given day. If you want to add rosemary to your breakfast scramble, whole grain mustard to your sandwich at lunch, and cumin and cayenne pepper to your chili for dinner, go right ahead! What can cause some problems, however, is if you eat way too much of one spice at one time. And of course, be aware of any potential interactions with spices and medication. And remember: With spices, a little goes a long way!