You Are Iron Deficient
Iron is an essential mineral that boosts oxygen deliver to your muscles. However, those who are prone to iron deficiency—particularly menstruating women—suffer lower metabolism as well. You can however, fix the lack at that time of the month by adding iron supplement or iron-rich foods to your diet (i.e., beans, spinach, lean beef, shellfish, and artichokes.

You Yo-Yo Diet
Yo-yo diets that drastically cut your calories might seem like a quick fix weight loss method. However, depriving your body of food and essential nutrients—like fats, complex carbohydrates, and vital proteins—will make your body believe it’s starving, and as a result, your metabolism will slow to a halt to conserve vital energy and nutrients for survival.

You Drink Too Much
It doesn’t matter what your poison is—fancy cocktails, wine, beer, or straight up liquor, drinking is hard on the body, particularly the liver and the metabolic processes. Why? Because consider each drink an obstacle that turns the metabolic process sluggish. The moral of the story—try to limit your alcoholic beverages to one to 2 per day at most.

You Fast or Cleanse
I know, I’ve always pondered a juice cleanse myself. And while it turns out that a few days of cleansing or fasting won’t do any damage, fast or cleanse for any longer and your body will believe its starving. This means your body will stall your metabolism in order to survive, which means it will promptly stop burning energy and stockpile all fat and energy.