Why do we experience worse PMS some months than others? Turns out, there is a connection between PMS and glucose. In fact, your blood sugar and menstrual cycle have a deep-seeded relationship that affects how you feel and how your body works during each phase of your cycle.

Studies show that glucose control changes throughout the menstrual cycle, so if you’re binging on carb-heavy and high-sugar foods, you might have worse cramps, lower energy, and an irritable mood. 

Meaning, we need to pay attention to what we eat during each phase to avoid significant blood sugar spikes and crashes. 

In this article, we’re going to talk about the importance of glucose levels throughout your cycle and the best ways to control them for healthy menstruation. 

Glucose Levels: What They Are & Why They Are Important 

Besides fat, glucose is another primary energy source for our bodies. Most of the glucose we use comes from foods like carbohydrates. If we consume too much glucose from sugar and high-carb foods, it can spike blood sugar and insulin release. Our bodies release insulin to help move glucose into our cells for storage to balance out blood sugar. But too much glucose and our blood sugar spikes and insulin floods. 

When all of that insulin floods in and we experience a blood sugar spike, our glucose levels drop, leading to a crash! That drop in glucose can express itself as brain fog, irritability, fatigue, or anxiety. 

If we experience chronic spikes and crashes, we can become insulin resistant, meaning our cells are numb to the effects and our bodies unknowingly produce more and more insulin.  

Insulin resistance contributes to nearly all chronic conditions (think Alzheimer’s, heart disease, diabetes) including fertility challenges. This is because it stimulates the ovaries to produce more testosterone, which can result in irregular menstruation. 

Being aware of what is happening in our bodies and how our food choices can affect our menstrual cycle are critical for keeping it on track. 

Menstrual cycle phases effect on glucose control  

The menstrual cycle is a fluctuation of hormonal changes (primary hormones being estrogen and progesterone) that affect several processes in the body, including how we handle glucose and blood sugar levels. Throughout the cycle, hormones will change via communication between the ovaries, uterus, and brain. 

While there are four phases, we will focus on the two main phases: the follicular and luteal phases, which are separated by ovulation. 

During the luteal phase, hormone levels are generally greater as progesterone is higher than estrogen because our bodies are preparing to nourish a fertilized egg. If there is no fertilization, hormone levels drop, leading to the follicular phase where estrogen tends to be higher than progesterone. 

The different ratios of hormones at each phase are what we believe determines our glucose control. The body attempts to conserve glucose for the parts of the cycle that demands more energy, like ovulation and building up the uterine lining. That means that glucose levels tend to be higher during the luteal phase post-ovulation, as research also shows. 

Higher levels of progesterone reduce insulin sensitivity, which means that insulin isn’t as good at flushing glucose from your system, leading to higher levels of circulating glucose. 

During the follicular phase when estrogen is dominant, glucose levels tend to be lower. Estrogen helps to modulate body fat and improve insulin sensitivity. (This makes sense because when estrogen levels drop postmenopause we sometimes see increased insulin resistance and a higher risk of type 2 diabetes.)

Understanding that our bodies are more insulin resistant after ovulation (when glucose is already super high), during the luteal phase, means that we should prioritize low-glycemic whole foods and avoid carb-heavy and sugary foods. High carbohydrate and sugary food intake could result in a significant blood sugar spike. If we do this, we can avoid feeling fatigued and experiencing brain fog. 

For more information on the causes of irregular periods and how you can regulate your cycle naturally, check out this article.