Parents, keep an eye out for RED-S red flags

By The Health News Team | December 14, 2023
Woman taking a break from running on the road

It might start with a missed period or two, or maybe a noticeable decline in an athlete’s speed on the field. Maybe it’s a burgeoning interest in eating “clean,” or a desire to increase the amount of time they’re training. Whatever the signs of Red-S might be, parents of athletes need to take notice.

RED-S, or relative energy deficiency in sport, was formerly known as the female athlete triad. It occurs when an athlete burns more calories than they take in. And regardless of whether it’s intentional or not, the lack of sufficient nutrition to fuel an athlete’s activity can lead to a variety of physical and mental health concerns.

“RED-S refers to an imbalance in your body's physiology due to low energy availability,” says Dr. Billy Hsu, a family and sports medicine doctor with Sharp Rees-Stealy. “This was more commonly seen when women would miss their period. But as of the last five to 10 years, there is growing evidence that males experience this also.”

Who is at risk for RED-S?

According to Dr. Hsu, RED-S is often seen in athletes that participate in endurance sports and sports with weight requirements. Other populations that are susceptible to RED-S are athletes with disabilities, focused on a certain body type or pressured to perform at high levels.

If RED-S is not recognized and addressed, there can be severe consequences.

“Your body has a natural way of maintaining homeostasis, or a state of balance,” Dr. Hsu says. “So, if it's not getting enough nutrition, certain parts of your body will start to shut down while energy is shunted to keep other parts working."

Most athletes know that there are performance consequences to not getting enough fuel into the body. But if an athlete is persistently not getting enough fuel — in the form of carbs, protein and fat — their overall health can be seriously affected, Dr. Hsu says.

According to the American Academy of Family Physicians, a lack of available energy to fuel activity can affect an athlete’s:

  • Energy levels

  • Periods

  • Bone health

  • Healthy growth and development

  • Normal heart function

  • Immune function

  • Ability to recover from workouts and heal muscle injuries

  • Mental health

“It’s a common misconception that a female athlete should have irregular or missed periods,” Dr. Hsu says. “Oftentimes, this is the first sign that the body is not getting enough fuel to support the athlete's needs.”

Recognizing and treating RED-S

While an athlete’s drive to succeed through watching what they eat and working to improve their strength and fitness are often celebrated, there is a point where over-training and inadequate nutrition can become serious health risks. It’s vital parents watch for signs their young athlete may have RED-S.

An athlete with RED-S may begin to fast, limit food or binge eat. They might also begin to exercise more than before and show mental health symptoms, including anxiety, depression, irritability and problems concentrating and sleeping.

Physical symptoms of RED-S include:

  • Fatigue

  • Weight loss

  • Dehydration

  • Stomach problems

  • Abnormal or absent periods

  • Bone loss

  • Stress fractures

  • Repeated muscle and tendon injuries

  • Decreased coordination

  • Cold intolerance

  • Slow heart rate

  • Low blood pressure

RED-S can also overlap with — or lead to — an eating disorder. The National Eating Disorders Association (NEDA) recommends an athlete with RED-S should be treated with a multidisciplinary team approach. The athlete’s doctor along with a nutritionist and mental health provider can work together to monitor the athlete’s physical health, ensure they are consuming adequate nutrition, and help them address mood changes and any underlying reasons for the development of RED-S.

Until the athlete receives clearance from their care team to resume activity and shows the willingness and ability to increase nutrition to adequate levels, regain and maintain lost weight, and do safe amounts of training, parents should ensure the athletes refrain from participating in their sport.

“RED-S must be treated,” Dr. Hsu says. “And the benefits of a good treatment team cannot be overstated.”

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