Relative Energy Deficiency in Sport (RED-S) Management Protocol

Athletic PerformanceModerate Evidence
10
supplements
2
Primary
8
Supporting
3
Grade A
135
Studies

Primary Stack

Core supplements with strongest evidence
2000-4000 IU daily (maintain serum >40 ng/mL; higher doses if deficient)

Essential for bone health; deficiency common in RED-S; supports bone mineral density and reduces stress fracture risk

25 studies1,500 participants
1500mg daily from diet + supplements (split doses)

Critical for bone health; inadequate intake common with energy restriction; prevents bone loss

20 studies1,200 participants

Supporting Stack

Additional supplements for enhanced results
As needed based on ferritin levels (target >50 ng/mL); test first

Deficiency common with low energy availability; essential for oxygen transport and energy metabolism

20 studies1,000 participants
2-3g EPA+DHA daily

Supports bone health, reduces inflammation, may help restore menstrual function

12 studies600 participants
100-200mcg MK-7 daily

Directs calcium to bones; works synergistically with vitamin D; supports bone mineralization

10 studies500 participants
300-400mg daily

Supports bone health, energy metabolism, and muscle function; often depleted in athletes

12 studies600 participants
15-30mg daily

Supports bone health and hormone production; often inadequate with energy restriction

8 studies400 participants
B-complex daily

Support energy metabolism; needs increased with training; often inadequate with caloric restriction

10 studies500 participants
10-15g collagen peptides with vitamin C daily

Supports connective tissue and bone matrix; may help with injury recovery

8 studies350 participants
500-1000mg daily

Supports collagen synthesis and immune function; enhances iron absorption

10 studies500 participants

How This Protocol Works

Simple Explanation

Relative Energy Deficiency in Sport (RED-S) occurs when athletes don't eat enough to support both their training and body's basic functions. Previously called the 'Female Athlete Triad,' we now know it affects all athletes. When energy availability is too low, the body starts shutting down non-essential functions - first reproductive hormones, then bone building, metabolism, and eventually cardiovascular and psychological health.

CRITICAL: RED-S is a serious medical condition requiring professional treatment. The PRIMARY treatment is increasing energy intake and/or reducing training load. Supplements DO NOT replace adequate nutrition.

Warning signs include:

•Menstrual irregularities or loss of period in females
•Low testosterone in males
•Recurrent stress fractures or injuries
•Declining performance despite training
•Fatigue, mood changes, difficulty concentrating
•Frequent illness

FIRST-LINE TREATMENT:

•Increase caloric intake - work with a sports dietitian
•Reduce training volume if intake cannot be increased
•Psychological support - often involves disordered eating
•Medical monitoring - bone density, hormone levels, cardiovascular screening

* Vitamin D and Calcium are essential. Athletes with RED-S have significantly increased risk of stress fractures and long-term bone loss. These supplements help but cannot fully compensate for low energy availability.

* Iron deficiency is common with energy restriction and affects performance and energy levels.

* Omega-3 Fatty Acids and Vitamin K2 provide additional bone support.

Expected timeline: Menstrual function often returns within 6-12 months of adequate energy availability. Bone density improvements take 1-2+ years. Full recovery requires sustained adequate nutrition - there are no shortcuts.

Clinical Perspective

RED-S (Relative Energy Deficiency in Sport): Syndrome from insufficient energy availability (EA) to support body functions after accounting for exercise expenditure. Previously 'Female Athlete Triad' - now recognized in all athletes. Low EA threshold: <30 kcal/kg FFM/day. Systems affected: menstrual/reproductive (amenorrhea, low testosterone), bone (low BMD, stress fractures), metabolic (reduced RMR), cardiovascular (bradycardia, hypotension), psychological (depression, impaired cognition), immune, GI, hematological.

CRITICAL: Primary treatment is restoring energy availability. Supplements are SUPPORTIVE, not corrective. Must address: 1) Energy intake (increase by 300-600 kcal/day minimum); 2) Training load (reduce if intake cannot increase); 3) Psychological factors (disordered eating, body image - often requires specialist); 4) Medical complications (bone loss, cardiovascular issues, hormonal). Oral contraceptives DO NOT fix bone loss - may mask amenorrhea while damage continues.

* Vitamin D (A-grade): Bone health critical. Systematic review: stress fractures (PMID: 28828084). IOC consensus: (PMID: 30084364). 2000-4000 IU daily; target >40 ng/mL.

* Calcium (A-grade): Bone protection. Review: (PMID: 19877092). 1500mg daily total - critical with low EA.

* Iron (A-grade): Common deficiency. Review: (PMID: 28252380). Test first; target ferritin >50 ng/mL.

* Omega-3 Fatty Acids (B-grade): Bone support; anti-inflammatory. Review: (PMID: 30084364). 2-3g EPA+DHA daily.

* Vitamin K2 (B-grade): Calcium utilization; bone. Systematic review: (PMID: 25516361). 100-200mcg MK-7 daily.

* Magnesium (B-grade): Bone; energy. Systematic review: (PMID: 28150472). 300-400mg daily.

* Zinc (C-grade): Bone; hormones. IOC review: (PMID: 30084364). 15-30mg daily.

* B-Complex (B-grade): Energy metabolism. Position statement: (PMID: 27015692). Daily.

* Collagen (B-grade): Connective tissue. Review: (PMID: 27852613). 10-15g with vitamin C.

* Vitamin C (B-grade): Collagen; iron absorption. Review: (PMID: 23075608). 500-1000mg daily.

Assessment targets: Energy availability calculation (ideally >45 kcal/kg FFM/day), BMD (DEXA), menstrual history/hormone levels, stress fracture history, RMR, cardiovascular screening (ECG, echocardiogram if concerning), psychological assessment, lab work (CBC, iron studies, vitamin D, metabolic panel).

Protocol notes: Energy availability: calculate EA = (energy intake - exercise energy expenditure) / FFM; <30 kcal/kg FFM/day = clinical RED-S; 30-45 = subclinical risk. Bone density: Z-score < -1.0 concerning in young athletes; < -2.0 = low BMD. Stress fractures: high-risk sites (femoral neck, navicular) need aggressive management and consideration of non-weight-bearing. Return to sport: gradual increase with demonstrated improved EA and clinical markers. Oral contraceptives: may restore bleeding but do NOT protect bone - not treatment for RED-S amenorrhea; may mask warning sign. Male athletes: low testosterone, decreased libido, fatigue - often underrecognized. Transdermal estrogen + progesterone: may be considered for bone in persistent amenorrhea with adequate EA. Psychological: disordered eating underlying ~50%; requires specialized treatment; may need sports psychology, ED specialist. Sport culture: pressure for leanness in gymnastics, distance running, cycling, wrestling, dance - education of coaches critical. Prevention: Regular screening (LEAF-Q questionnaire), education, supportive sport environment. Career implications: long-term bone loss may not fully recover; early intervention critical.