Protocol · Athletic Performance
Relative Energy Deficiency in Sport (RED-S) Management Protocol
Vitamin D and Calcium are the core of this stack, with 8 supporting supplements. Each row gives the amount the protocol lists and the grade our evidence database holds for that supplement in Relative Energy Deficiency in Sport (RED-S) Management.
We are re-verifying the studies cited on protocol pages; only confirmed citations are shown.
The stack
10 supplements · none graded yet
| Grade | Supplement | Amount listed | Why it’s in the stack | Evidence on file | Shop |
|---|---|---|---|---|---|
| Primary stackThe core of this protocol | |||||
| Vitamin D | Amount listed: 2,000–4,000 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 | Not graded yet | ||
| Calcium | Amount listed: 1,500 mg daily from diet + supplements (split doses) | Critical for bone health; inadequate intake common with energy restriction; prevents bone loss | Not graded yet | ||
| Supporting stackListed as additions to the core | |||||
| Iron | Amount listed: 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 | Not graded yet | ||
| Omega-3 Fatty Acids | Amount listed: 2–3 g EPA+DHA daily | Supports bone health, reduces inflammation, may help restore menstrual function | Not graded yet | ||
| Vitamin K2 | Amount listed: 100–200 mcg MK-7 daily | Directs calcium to bones; works synergistically with vitamin D; supports bone mineralization | Not graded yet | ||
| Magnesium | Amount listed: 300–400 mg daily | Supports bone health, energy metabolism, and muscle function; often depleted in athletes | Not graded yet | ||
| Zinc | Amount listed: 15–30 mg daily | Supports bone health and hormone production; often inadequate with energy restriction | Not graded yet | ||
| B-Complex Vitamins | Amount listed: B-complex daily | Support energy metabolism; needs increased with training; often inadequate with caloric restriction | Not graded yet | ||
| Collagen | Amount listed: 10–15 g collagen peptides with vitamin C daily | Supports connective tissue and bone matrix; may help with injury recovery | Not graded yet | ||
| Vitamin C | Amount listed: 500–1,000 mg daily | Supports collagen synthesis and immune function; enhances iron absorption | Not graded yet | ||
Shop the evidence-backed picks
Support alongside medical care. These supplements are not a treatment for the condition on this page. If you are being treated for it, talk to your clinician before adding one: supplements can interact with medicines.
The collection holds the supplements we grade A or B for its theme, in third-party tested products where the catalog has them. It opens in our Fullscript store. You can look through it without signing in; Fullscript asks for a free account to order.
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Each opens third-party tested products, matched to the dose above where we can.
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How this protocol works
In plain language
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.