Magnesium Glycinate vs Soy Protein Isolate
Sleep vs Protein · evidence-backed comparison
- • Magnesium Glycinate has the broader effect profile across the 9 effect categories.
- • Magnesium Glycinate is cheaper per serving ($0.25 vs $0.60).
- • Magnesium Glycinate has a slightly cleaner safety profile.
- • Magnesium Glycinate has higher bioavailability (better absorption).
Side-by-side traits
| Trait | Magnesium Glycinate | Soy Protein Isolate |
|---|---|---|
Category | Sleep | Protein |
Active compound | Magnesium chelated to glycine | Soy isoflavones + amino acid blend |
Form available | Capsule, Powder, Tablet | Powder |
Source | synthetic | plant |
Typical dose | 200–400 mg elemental Mg | 25–40 g per serving |
Dose range | 200–400 mg | 25–40 g |
Loading protocol | — | — |
Best taken with | evening, with water | water or plant milk |
Best time of day | evening | post-workout |
Bioavailability How efficiently the body absorbs and utilizes the compound. | Very High (5/5) | High (4/5) |
Onset time | Acute: 1–3 hours | Acute: 45–75 min |
Half-life | ~28 hours (Mg) | — |
Evidence level Quality and quantity of human research. | Moderate (some RCTs) | Moderate (some RCTs) |
Overall effect Subjective effect magnitude. | Moderate (3/5) | Moderate (3/5) |
Muscle / strength | Moderate (3/5) | High (4/5) |
Physical energy | Low (2/5) | Low (2/5) |
Focus / cognition | Low (2/5) | Very Low (1/5) |
Mood / stress | Moderate (3/5) | Low (2/5) |
Sleep quality | High (4/5) | Low (2/5) |
Immunity | Low (2/5) | Low (2/5) |
Recovery Post-exercise recovery support. | Moderate (3/5) | High (4/5) |
Longevity / healthspan | High (4/5) | High (4/5) |
Safety rating 5 = exceptionally well-tolerated; 1 = significant risk profile. | Very High (5/5) | High (4/5) |
Price per serving Approximate USD per typical daily dose. | $0.25 | $0.60 |
Vegan friendly | Yes | Yes |
Gluten free | Yes | Yes |
3rd-party tested | Yes | Yes |
About Magnesium Glycinate
The best-tolerated, best-absorbed magnesium form for sleep and stress. Doesn't cause loose stools like citrate.
About Soy Protein Isolate
Complete plant protein with all 9 EAAs. Equivalent muscle-building to whey in older adults; mild cardio-protective effects from isoflavones.
Vetted brands, third-party testing, ships worldwide.
Vetted brands, third-party testing, ships worldwide.
Magnesium Glycinate safety
Common side effects:
- • Mild laxative effect (rare)
- • Drowsiness
Avoid if:
- • Severe kidney disease
Drug interactions:
- • Bisphosphonates
- • Antibiotics (timing)
Soy Protein Isolate safety
Common side effects:
- • Mild estrogen-mimicking (debated, minor)
Avoid if:
- • Soy allergy
- • Hormone-sensitive cancers (consult MD)
Drug interactions:
- • Thyroid meds (levothyroxine)
Common uses
- • Sleep quality
- • Anxiety
- • Muscle cramps
- • RLS
Stacks well with: Zinc, Vitamin D3, Melatonin
Common uses
- • Vegan muscle gain
- • Heart health
- • Menopause support
Stacks well with: Creatine Monohydrate
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Medical disclaimer
SupplementDuel is for educational purposes only and is not medical advice. Consult a physician before starting, stopping, or combining supplements — especially if you are pregnant, breastfeeding, take prescription medication, or have a chronic condition.