Last month, I drove to the gas station in the middle of the night for a chocolate bar. I ate a whole bag of potato chips last week because I needed something salty. As I write this, I’m resisting the urge to bake cookies to satisfy my sweet tooth. What’s up with these cravings? Is my body trying to tell me something? — Craved and Confused

Don’t worry, Craved and Confused, most food cravings are totally normal — they are the body’s signal to eat for pleasure. A common cause of cravings is a strict diet that totally eliminates a type of food. Cold-turkey cutouts typically make cravings even stronger. But If you’re not dieting, keep reading — there are many theories as to what exactly causes you to crave particular foods.

Pretty much everyone has craved a bag of potato chips or a large order of fries. In one study published by the American Journal of Clinical Nutrition, scientists induced a substantial sodium-depletion in 10 volunteers. At the end of the treatment, the participants desired salty foods more than normal. Naturally, this craving ensures that their sodium deficit would be restored. In this case, they subjects craved sodium because of a biological need. 

In today’s packaged and fast food society, however, such sodium deficiency is rare. On average, Americans consume 1,100 mg more sodium than recommended per day, according to the CDC.  

So why do we crave salt when we’re obviously consuming enough? Our preference for salty food is likely the result of the standard levels we are exposed to. (tThank you, processed foods.) Our “need” for salty snacks is more about preference in taste than biological requirement, according to Nutrition Today. But there’s good news: The inclination for salty foods is changeable. Individuals who start a low-sodium diet will eventually adjust to a less salty menu.

If doughnuts, ice cream and cupcakes are on your mind, trade the pastry for a pillow. A study published in Obesity found that when young men were deprived of sleep, their blood work showed higher levels of the hormone ghrelin. Special cells in the stomach release ghrelin which tells your brain, “Feed me!” The sleep-deprived men also had an increased appetite for high-carbohydrate and high-calorie foods. 

Craving ice or other non-nutritive substances such as clay, dirt or paper? You may be suffering from an iron deficiency. This symptom is much more common in women and kids, according to the American Journal of Hematology. Boost your iron intake by consuming lean meats, poultry and seafood. Vegetarians: Fill up on lentils, beans and iron-fortified grain products.

This article wouldn’t be complete without mentioning the most commonly craved food among North American women: chocolate. Chocolate’s unique taste and texture is one popular reason why it may be so highly desired, according to Nutrition Reviews. 

Some say craving chocolate is a way to self-treat a magnesium deficiency. But if this were the case, we would all be reaching for magnesium-rich spinach as well, and personally, leafy greens rate pretty low on my list of cravings. 

Perhaps the most likely reason we seek out chocolate is because it makes us feel good. One scientific review in Nutrition Reviews found that in five out of six studies examined, chocolate eased negative moods or improved current mood state. So our chocolate craze could be all in our heads.

Now that you know the causes behind pesky cravings, you can form a game plan to combat them. If you believe you do have a nutrient deficiency, or your cravings are out of control, speak with your medical doctor or a registered dietitian. Remember that all foods (even those that are craved) can have a place in your diet when consumed in moderation.