Hot peppers like jalapenos and chilis contain capsaicin, which may give them a fat-burning effect. “Studies show that capsaicin reduced belly fat in men and women by oxidizing fat,” McCarthy said. “Capsaicins have also been found to increase resting metabolic rate, thus increasing the rate in which your body burns fat and or calories at rest.”
Aside from being a whole food, lentils are a good source of iron — and many of us are short on that nutrient. If your body lacks an essential nutrient like iron, it’s not going to be working as efficiently as it should, slowing your metabolism.