Stress hormone production:

When the body does not have adequate nutrients, especially carbohydrates, it enters a starvation state. Here, the body produces high levels of stress hormones including cortisol and adrenaline in order to increase blood glucose levels and meet energy needs. Cortisol directly opposes the thyroid hormones, which assist in increasing metabolic rate and burning food for energy. Studieshave demonstrated that elevated cortisol levels are positively associated with increased waist circumference and increased abdominal adipose (fat) tissue.

Imbalanced blood sugar:

Without a constant supply of energy, or carbohydrates, to cells, they cannot function properly. Undereating commonly leads to imbalances in blood sugar–especially dips in blood glucose during long periods of fasting. This stresses the body and various organs such as the liver, which must then synthesize sugars from muscle tissue in order to meet energy needs. This can actually slow detoxification, increase stress hormones, prevent adequate sleep, and prevent the body from burning energy long term. Again, the body feels unsafe during blood sugar spikes and dips, so it responds by holding on to nutrients leading to weight gain. Stable blood sugar is only possible when eating sufficient nutrients and calories. More on this here!

Thyroid suppression:

The thyroid is the “master thermostat of the body.” This means that the thyroid gland controls energy production and heat, also referred to as metabolic rate. In states of fasting or caloric restriction, the thyroid actually slows down production of thyroid hormones needed to burn calories and produce energy for cells. This can result in a slowed metabolism, weight gain, and other chronic symptoms such as fatigue. The thyroid responds very accurately to energy needs, so when food intake decreases, the thyroid will stop burning energy at a high rate in order to conserve energy. Another important component of thyroid health is eating adequate nutrients such as carbohydrates, selenium, copper, and zinc–all of which play a role in thyroid hormone production. It is difficult to meet these when chronically undereating.

Changes in sex hormones:

Undereating can lead to changes in sex hormones, which can cause weight gain and other menstrual or reproductive imbalances. For example, when restricting calories, the thyroid slows and stress hormones increase. This directly impacts all sex hormones – but predominately lowers estrogen, which shifts opportunity for ovulation, and thus impairs the production of progesterone, a protective hormone necessary for reproduction and a high functioning metabolism. Decreased   estrogen also can lead to irregular periods and other menstrual symptoms. Low estrogen and progesterone are associated with decreased muscle mass and increased fat synthesis, which ultimately indicate a suppressed metabolism.  We also can see PCOS related changes here as a result of undereating.  Most of my PCOS women come to me with the impression that they are eating too much and should avoid all carbs, on the contrary, this practice actually could be digging them into a deeper hole!  Stress and blood sugar dysregulation are two of the biggest drivers of androgen imbalances. Undernourishing impacts both stress and blood glucose regulation- creating an ideal environment for testosterone to reactively increase.

Here are a few signs you may be undereating:

• Chronic fatigue
• Brittle hair and nails
• Hair loss
• Hyper fixation on food
• Tendency toward negative thought patterns
• Inability to maintain boundaries
• Poor mental resilience
• Cold hands and feet
• Frequently waking in the middle of the night
• Unexplained weight gain
• Chronic constipation
• Bloating
• Missing periods
• Irregular cycles
• Sex hormone imbalances
• Low sex drive
• Poor circulation
• Infertility

Eat a balanced breakfast within 1 hour of waking:

This is another important component of blood sugar balance. Upon waking, our glycogen stores are depleted and we need to eat to replenish our bodies with adequate nutrients and energy. If we choose to fast, the body must rely on stress hormones for energy which can lead to other hormone imbalances and tissue breakdown.

Combine protein, carbohydrate, fat, and fiber at every meal:

Pairing different macronutrients is especially helpful for ensuring that we are getting adequate vitamins and minerals. Eating protein and carbohydrates together ensures that blood sugar does not spike too high, that muscle protein is not wasted, and that cells can adequately use sugar. Fat and fiber similarly slow absorption of carbohydrates, ensuring a constant supply of energy after eating.

Prioritize mineral intake:

Minerals play an important role sugar metabolism, thyroid hormone production, and sex hormone balance. Eating for adequate minerals including sodium, potassium, magnesium, calcium, copper, zinc, etc. is essential for proper cell functioning, detoxification, and fertility. Unfortunately, our soil is becoming increasingly depleted of minerals, so it is important to be mindful of mineral intake to meet dietary needs. It is likely that when one is chronically undereating, they are deficient in minerals. To learn more about how to meet mineral needs, check out this post!

Consider nutrient density:

Diet culture and mainstream nutrition advice have long promoted the idea that women should eat low calorie foods such as salads and low-fat processed foods to stay thin. While this may help cut calories, the foods promoted are often lacking in essential nutrients. Eating this way long term can decrease the body’s ability to cope with stress, decrease cell function, detoxification, etc. Prioritizing a variety of nutrient-dense foods such as animal proteins, fruits and root vegetables, and healthy fats ensures adequate vitamin and mineral intake.

Tune into your body’s cues:

Taking time to tune into internal cues is one the most important things we can do to restore hormonal balance and increase metabolism. Eating when hungry and resting when the body cues us is essential for proper energy use and production. The body is highly intuitive and always signals us to what it needs. Taking time to slow down, be mindful, and reconnect with your body can help you appropriately address hunger cues.

Consider a bedtime snack:

Women who are undereating frequently wake up in the middle of the night. It is a common misconception that the body is waking you up to use the bathroom. More often than not, however, blood sugar levels have dipped too low causing you to wake up. Eating a small snack with protein and carbohydrates before bed can help keep liver glycogen stores up and allow you to sleep restfully throughout the night.