RED-S or Relative Energy Deficiency in Sport is a serious condition that can negatively impact both male and female athletes.

Staying adequately fueled is essential for athletes. You consistently burn energy daily from simply doing everyday tasks. With prolonged exercise, your body burns even more energy. To replace this lost energy, you have to consume energy from food in the form of calories.

Because athletes are burning more energy with their increased exercise, they need to eat more calories to compensate. If you aren’t getting enough calories, your body doesn’t have enough energy to keep up with your exercise demands.

This deficiency in calories can have serious short and long term effects on your body. Eventually it could lead to developing low energy availability, also known as Relative Energy Deficiency in Sport, or RED-S.

Keep reading to learn more about what RED-S is, common symptoms to watch out for, and my best dietitian-approved tips to prevent and treat RED-S.

What is RED-S?

Relative Energy Deficiency in Sport (RED-S) refers to poor health and worsening athletic performance when athletes are not taking in enough fuel to support their training demands.

You may have heard of the former name of RED-S, known as the Female Athlete Triad, which was changed to include both women and men. This previously referred to female athletes who were underfueling and overexercising, causing three main symptoms: disordered eating, irregular menstruation, and bone loss.

Now, RED-S encompasses a larger list of symptoms that both men and women experience. An athlete’s risk for RED-S increases as they continue to exercise without refueling properly.

Certain sports see an increase in RED-S when athletic success is tied to a thin or small body that can cause disordered eating habits. Such sports include but aren’t limited to figure skating, gymnastics, and diving.

Other sports with frequent weigh-ins, like wrestling and lightweight rowing, can cause athletes to cut back on calories and seek extreme measures to make weight.

Symptoms of RED-S

The signs of symptoms of RED-S differ for every athlete. RED-S is frequently undiagnosed because the symptoms either go unnoticed or may be mistaken for another illness or disorder.

The most common symptoms of RED-S to look out for include:

• Fatigue
• Rapid weight loss
• Irritability, anxiety, and depression
• Hair loss
• Trouble staying warm
• Low libido (male athletes)
• Missed periods or delayed puberty (female athletes)
• Frequent illness
• Increased injuries
• Difficulty concentrating
• Dehydration

Consequences of RED-S

RED-S is brought on by either not eating enough fuel and/or exercising too much. When you have a low availability of energy, your body’s functions start to not work properly. It will try to compensate for the lack of energy available, disrupting your hormonal and metabolic systems.

The development of RED-S can have serious consequences on not only athletic performance but also overall health.

Protein synthesis: By not consuming enough calories as an athlete, you reduce the protein synthesis in your body. This leads to muscle loss and slow recovery after training. Even though you exercise more, your body is too exhausted to turn your training into building muscle.

Bone health: RED-S puts immense stress on the body,, affecting hormones like cortisol, estrogen, and testosterone. Because of this, bone density is negatively affected and can lead to irreversible bone loss in athletes. Bone loss increases your risk of fractures and injuries, a major concern for athletes.

Nutrition deficiencies: Because those with RED-S are not consuming enough calories, it is likely they are not getting enough vitamins and minerals in their diet. Low energy availability over time can lead to nutritional deficiencies. In turn, you may experience side effects, including frequent infections, fatigue, and hair loss.

Tips on How to Prevent and Treat RED-S

The best thing you can do as an athlete is prevent low energy availability from occuring is staying nourished and fueling your body with enough calories.

If you struggle with how to add more food into your day, try following these tips below.

1. Increase your current portion sizes: If you’re having trouble fitting extra meals into your day, increase your current portions. I would suggest to focus mainly on protein sources for muscle and carbs for energy. Try 6 oz of chicken instead of 4 oz or a double serving of rice at dinner. Check out my previous blog on protein intake to learn more!
2. Meal prep in advance: Have a busy training schedule? Meal prep on a rest day or before practice when you have energy. This way, you have meals ready to go in between training sessions and won’t miss a meal.
3. Choose nutrient-dense foods: Pick higher calorie options or add extra fats to your meals to boost your caloric intake. Some healthy fats you can add to meals include nuts, seeds, and avocado.
4. Create a basic meal schedule: Meal planning can be a helpful strategy for athletes to make sure you are eating enough throughout the day. Especially if you have a very demanding schedule and find it hard to fit in meals! It doesn’t need to be complicated, either. Sit down at the beginning of your week and make a rough plan of what your meals will look like for the week.
5. Ditch the fad diets. Disordered eating habits like following fad diets and restricting food intake can contribute to developing RED-S. As an athlete, it may be tempting to follow the latest trendy diet. But your body needs fuel and restricting your intake will only harm your training in the long run.

Bonus tip: a deficiency in vitamin D has been linked to the development of RED-S. Make sure you are getting enough sunlight and eating food sources of vitamin D such as eggs yolks. If your levels are still low, a quality supplement may be helpful.

The Bottomline

As an athlete or avid exerciser, it is your job to make sure you are eating enough energy to fuel your workouts. RED-S is a serious condition that can have long-term impacts on both athletic performance and overall health.

• Relative Energy Deficiency in Sport (RED-S) relates to poor health and worsening athletic performance that occurs when an athlete is not taking in enough fuel to support their training demands.
• RED-S symptoms vary between athletes and may be mistaken for another illness or disorder. Common signs and symptoms include dizziness, irritability, and rapid weight loss.
• RED-S can cause loss of muscle mass, irreversible bone loss, and nutrient deficiencies.
• Prevention and treatment of RED-S include increasing portion size, meal prepping, choosing nutrient-dense foods, and checking in your eating habits.

Don’t let RED-S keep you from hitting PR’s and training your best! Working with a dietitian (like myself!) can help you come up with a meal planning strategy that ensures you are getting the fuel you need.

Head over to my services page to learn more about my 1:1 nutrition coaching offers. There is no better time to invest in your health!