If you've ever met someone who seems to eat whatever she wants without gaining an ounce, while you seem to gain weight just looking at a slice of pizza, you've seen the power of a fast metabolism. Unfortunately, many of the factors that affect your metabolism -- including your genetics, age and gender -- are outside your control, but a few diet and exercise tweaks can slightly boost your metabolic rate. There is some evidence that spicy foods, like hot sauce, can modestly boost your metabolism and help with weight loss, but hot sauce isn't a magic bullet.
Hot Sauce, Capsaicin and Calorie Burn
There's some evidence that capsaicin -- the "hot" chemical in hot sauce -- can boost your metabolism, according to a literature review published in Chemical Senses in 2012. The review notes that several studies have linked capsaicin to a temporary increase in body temperature -- which boosts your calorie burn, because your body has to expend energy lowering your temperature back down to normal. Several studies outlined in the review also link capsaicin to greater fat oxidation -- which means it helps boost fat burning.
If you're following a restricted-calorie diet for weight loss, adding a little spice to your diet might help increase your metabolism, reports a study published in PLoS One in 2013. Your body naturally slows your metabolism when you go on a weight loss diet, as a response to your lower calorie intake. The researchers found that adding capsaicin to a weight loss diet can partially offset that reduction, keeping your calorie burn higher to facilitate weight loss.
However, not all studies have yielded the same results, and some of the research presented in the 2012 review article didn't find that capsaicin significantly increased calorie burn. In addition, the researchers in the PLoS One study didn't track weight loss in its study subjects -- it just looked at their metabolic rates -- so it's not clear whether adding the capsaicin actually increased weight loss.
Capsaicin and Your Appetite
Although hot sauce's effect on your metabolism still requires more investigation, adding more fire to your diet might help you lose weight by controlling your appetite. One study, published in the International Journal of Obesity in 2006, found that people who ate capsaicin as part of their diets reported feeling more satisfied and full after meals than people who didn't, and they also ate less calories and fat.
Another study, published in the June 2014 issue of Appetite, found similar results. The study subjects who consumed capsaicin felt more satisfied after their meals and, given the opportunity to eat as much as they wanted, were less likely to overeat than those who didn't get capsaicin.
If you normally feel hunger pangs mid-morning or -afternoon, or feel yourself drawn to the pantry for midnight snacks, try adding more hot sauce to your meals to prevent hunger and accidental snack binges between meals.
Other Weight-Loss Benefits of Hot Sauce
Hot sauce is essentially calorie-free. Two commercially available hot sauces and hot chili sauce each contain just 1 calorie per teaspoon, so you can add as much hot sauce to your meals as you'd like without going over your daily calorie intake. Use hot sauce to add flavor to vegetables, fish and meat. Try lightly coating chopped veggies in hot sauce before roasting, using a mixture of lime or lemon juice with hot sauce for a low-calorie marinade for chicken breasts; mix olive oil, hot sauce and just a touch of honey for a healthful salad dressing.
Capsaicin has another potential benefit during weight loss -- it may help your body absorb micronutrients, like vitamins and minerals, in your food, according to a literature review published in Critical Reviews in Food Science and Nutrition in 2015. When you're eating a restricted-calorie diet, every calorie counts, and adding hot sauce can help you get the most nutritional value for your foods.
Other Metabolism Boosters
While adding hot sauce to your diet certainly won't hurt your metabolism, and appears to offer benefits, you shouldn't count on hot sauce alone to maximize your metabolism. Make sure you're also staying active with cardio and strength training. Cardio directly boosts your calorie burn, and interval training -- where you alternate very intense working periods with lower-intensity resting periods -- can elevate your calorie burn for hours after a workout. Strength training helps you build muscle tissue, as well as retain the muscle tissue you have. Because muscle is metabolically active, adding lean mass increases your daily calorie burn, boosting your metabolism.
If you're concerned that you have a slow metabolism, talk to your doctor. Some health conditions, such as an underactive thyroid, can slow your metabolism, and a professional can help diagnose and treat a potential health condition.