Cravings before a period are extremely common and are driven by predictable biological changes within the menstrual cycle. These pre-menstrual cravings (PMC) are typically characterized by an intense desire for high-calorie, high-carbohydrate, or comfort foods, such as chocolate, salty snacks, or refined sweets. This desire for particular foods is a recognized symptom of Premenstrual Syndrome (PMS). Understanding the underlying mechanisms—the hormonal fluctuations and the subsequent effect on brain chemistry—can help validate and manage this recurring experience.
The Estrogen and Progesterone Rollercoaster
The primary driver of increased appetite and generalized hunger is the shift in sex hormones that occurs during the luteal phase, the time between ovulation and the start of menstruation. During this phase, the body prepares for a potential pregnancy, leading to an increase in both progesterone and, initially, estrogen, followed by a sharp drop in both if conception does not occur. This hormonal environment affects the body’s energy expenditure and appetite regulation.
Progesterone has a thermogenic effect, meaning it slightly raises the resting metabolic rate (RMR) and basal body temperature. Research suggests that this increase in RMR during the luteal phase can raise the body’s caloric needs by an estimated 100 to 300 calories per day. Consequently, the body sends stronger hunger signals, prompting an increase in overall food intake.
The appetite-suppressing effect of estrogen, which is higher during the first half of the cycle, is essentially reversed by the presence of progesterone in the luteal phase. Studies have noted that total calorie intake can be significantly higher during the luteal phase compared to the follicular phase, with some research indicating an increase in energy intake ranging from 12% to 38%. This metabolic demand explains the feeling of a general, deep hunger that precedes menstruation.
The Link Between Cravings and Serotonin Production
Distinct from the overall caloric need, the intense craving for specific comfort foods, especially those high in sugar and carbohydrates, is linked to changes in brain chemistry. In the days before a period, the decline in estrogen levels leads to a temporary dip in the production and function of serotonin, often called the “feel-good” neurotransmitter. Low serotonin levels can contribute to mood symptoms associated with PMS, such as anxiety, irritability, and low mood.
The body attempts to self-medicate this mood dip by seeking out foods that temporarily boost serotonin. Consuming carbohydrates, particularly simple sugars, triggers a rapid release of insulin. This insulin surge clears other amino acids from the bloodstream, which allows tryptophan—the precursor to serotonin—a clearer path to cross the blood-brain barrier.
Once tryptophan reaches the brain, it is converted into serotonin, providing a temporary sense of calm and improved mood. This process creates a cycle where the body learns to crave sugary and starchy foods for their mood-boosting effect, leading to desires for chocolate, cakes, or refined snacks. The preference for high-fat and high-carb foods may also be driven by elevated levels of the stress hormone cortisol, which can fluctuate along with estrogen.
Strategies for Balancing Pre-Period Hunger
Managing these dual-driven cravings involves addressing both the metabolic need for energy and the neurochemical need for a mood boost. A helpful dietary strategy is to prioritize complex carbohydrates over simple sugars to stabilize blood sugar and maintain sustained serotonin production. Opting for whole grains, oats, brown rice, and legumes provides the necessary tryptophan precursor without the sharp insulin spike and subsequent energy crash of refined sweets.
Incorporating magnesium-rich foods can be beneficial, as magnesium is involved in over 300 biochemical reactions, including the production of serotonin. Foods such as leafy green vegetables, nuts, seeds, and dark chocolate (at least 75% cacao) can help alleviate symptoms like mood swings and bloating while reducing the intensity of cravings.
Ensuring adequate hydration is a simple but effective measure, as thirst can sometimes be confused with hunger signals. Moderate exercise, even a brisk walk, naturally increases serotonin levels and helps to manage the emotional and physical discomfort of the premenstrual phase. Focusing on sustained energy and nutrient density, rather than restriction, supports the body’s increased energy demands during the luteal phase.