Why am I not getting my period? A Dietitian’s Guide to Health & Hormones

Menstrual cup. Used by some women during their menstrual cycle.

Missing periods in athletes isn’t something to ignore. It’s a key signal from the body-and as a sports dietitian, it’s often one of the first clues that energy balance is off.

Let’s dive into what causes period loss, what it means for long-term health and performance, and how nutrition can help get things back on track.

What Your Missing Period Is Trying to Tell You?

When menstruation stops due to training and nutrition imbalances, it’s called athletic amenorrhea. This is often part of a bigger picture known as the Female Athlete Triad, which includes:

• Low energy availability

• Menstrual dysfunction

• Low bone density

In many cases, the root cause is simple: the body isn’t getting enough energy to support both athletic output and essential functions like hormone production.

Why Fueling Matters: The Nutrition-Hormone Connection

A vibrant salad full of different nutrients which is essential for avoiding low energy availability.

You don’t have to restrict food intentionally. Low energy availability (LEA) can happen when energy intake doesn’t meet the body’s needs after training. Common signs:

• Missing or irregular periods

• Always cold or tired

• Stress fractures or frequent injuries

• Trouble focusing or sleeping

• Slowed recovery

Even if an athlete is eating “clean,” it may not be enough. This is where a dietitian plays a critical role- identifying deficits, not just in calories, but in macronutrients and timing.

How to Get Your Period Back: A Nutrition-Led Approach

Step 1: Eat More-Yes, Really

Boosting total energy intake is step one. Tips:

• Add energy-dense snacks (nut butters, trail mix, dried fruit)

• Never skip meals, especially around training

• Reintroduce fats (key for estrogen production)

• Prioritise carbs, especially before and after workouts

Remember: you can’t out-train low fuel.

Step 2: Adjust Training, If Needed

For some, reducing training load helps kickstart hormonal recovery. That might mean fewer high-intensity sessions or more rest days. If an athlete resists this, use data-like changes in recovery, sleep, and heart rate variability to help make the case.

Step 3: Monitor, Track, Support

Track:

• Energy intake and training load

• Return of menstrual cycles

• Hormone labs, if available

• Bone density (especially if amenorrhea lasts >6 months)

Support the process with a multidisciplinary team: physician, dietitian, coach, and mental health pro (especially if disordered eating is present).

Long-Term Risks of Ignoring a Missing Period

This isn’t just about short-term hormone shifts. Long-term athletic amenorrhea increases the risk of:

• Osteoporosis and stress fractures

• Fertility issues

• Mood disturbances

• Poor immune function

• Reduced performance due to chronic under-recovery

• RED-S

And no-losing a period doesn’t mean you’re more “dedicated.” It’s a sign your body is underfed and overworked.

How Dietitians Can Help: Prevention + Recovery?

Education Is Power:

We can help athletes understand that:

• A regular period = a functioning, fueled body

• More food doesn’t mean weight gain—it means recovery

• Performance improves when the body is hormonally healthy

• Missing a period isn't normal as it can be a sign of RED-S

FAQs: Athlete Period Loss, Nutrition & Recovery

1. How many missed periods is a red flag?

Missing three or more periods in a row (without pregnancy or birth control influence) is clinically considered amenorrhea. Act early by seeing a medical professional, such as a Dietitian.

2. Can an athlete still perform well without a period?

Short-term? Maybe. Long-term? No. Missing periods and sports performance are linked; low fuel leads to poor recovery, fatigue, and injury risk.

3. Can diet alone bring back a period?

Yes-in many cases, period recovery for athletes begins with consistent nutrition changes: higher energy availability, better meal timing, and carb/fat inclusion. But in prolonged cases, medical evaluation is needed.

A missing period isn’t just “normal for athletes”-it’s a loud message from the body. With the right nutrition strategy, hormonal health can be restored, and performance can thrive. At Nutrition & Co we want to help you achieve your full potential. Don't let under-fuelling limit your performance and health-book a consultation with our specialist dietitians today!