Supplements & Electrolytes
Fill the gaps — but get the basics right first
Supplements are not magic. They work best when the foundations — sleep, food, exercise — are already in place. That said, several have robust evidence behind them and fill genuine gaps that diet alone often can't cover.
The Supplements Worth Taking (With Doses and Evidence)
| Supplement | Dose | Evidence | What it does | Notes & cautions |
|---|---|---|---|---|
| Vitamin D3 + K2 | 2,000–5,000 IU D3 + 100–200 mcg K2 | ✓ Strong | Deficiency is extremely common globally. D3 is essentially a hormone — it supports immunity, mood, bones, and muscle. K2 ensures calcium goes to bones, not arteries. | Take with a meal containing fat. Get your levels tested first (target 40–60 ng/ml). |
| Magnesium Glycinate | 300–400 mg (evening) | ~ Moderate | Over 300 bodily processes need magnesium. Modern diets are frequently deficient. Supports sleep, reduces cortisol, and improves insulin response. Note: the clinical trial behind the sleep-benefit claim used magnesium oxide, not the glycinate form — glycinate's better absorption is plausible but hasn't been separately trial-verified for this outcome. | Take in the evening. Avoid magnesium oxide — poor absorption. Don't exceed 400 mg without guidance. |
| Omega-3 (EPA + DHA) | 1–3 g combined/day | ~ Moderate | Reduces whole-body inflammation. Supports brain, heart, and joint health. Especially important if you eat little oily fish. | Triglyceride form absorbs better than ethyl ester. Keep refrigerated. Allow 8–12 weeks to see effects. |
| Creatine Monohydrate | 3–5 g/day | ✓ Strong | The most studied sports supplement in history. Improves strength, power, and recovery — and growing evidence supports cognitive benefits too. | No loading phase needed. Cheap, safe, and extremely well researched for long-term use. |
| Zinc (bisglycinate) | 15–30 mg/day | ~ Moderate | Essential for testosterone production, immune function, and wound healing. Many people are mildly deficient, especially those who sweat a lot. | Long-term use: add 1–2 mg copper to prevent depletion. Don't exceed 40 mg/day. |
| Ashwagandha (KSM-66) | 300–600 mg/day | ~ Moderate | Root extract shown in human trials to reduce cortisol, improve sleep onset, and mildly improve exercise capacity. | Can cause GI upset. Rare liver injury reports. May interact with thyroid medication, sedatives. Cycle 2–3 months on / 1 month off. |
| L-Theanine | 100–200 mg | ~ Moderate | Promotes calm focus without drowsiness. Works particularly well paired with caffeine — reduces jitteriness while keeping alertness. | Classic ratio: 200 mg theanine to 100 mg caffeine. Very well tolerated. Also useful before bed. |
| NMN or NR | 250–500 mg/day | ? Emerging | Raises NAD+ levels in the body. NAD+ is essential for cellular energy and DNA repair — and it declines significantly with age. | Consistently raises NAD+ biomarkers in human studies. Whether this translates to meaningful healthspan benefits in healthy people is still being researched. |
| Alpha-GPC / Choline | 300–600 mg | ~ Moderate | Your brain uses choline to make acetylcholine — the chemical of focus and memory. Many people don't get enough from diet alone. | Best taken before mentally demanding tasks or exercise. Eggs are also a great dietary source. |
| Apigenin | 50 mg (evening) | ~ Moderate | A plant compound (found in chamomile) that slows the breakdown of NAD+ and acts as a mild calming agent to support sleep. | Very low toxicity. Often paired with NMN/NR in longevity protocols. |
Electrolytes — the overlooked essential
Sodium, potassium, and magnesium need to be in balance for your muscles, heart, and brain to work properly. Signs of imbalance include muscle cramps, headaches, fatigue, and brain fog.
- Sodium: don't fear it if you're active and eat mostly whole foods — sweat removes a lot. Add a pinch of sea salt to water during exercise.
- Potassium: most people eat too little — avocado, bananas, sweet potato, leafy greens, and legumes are excellent sources.
- Magnesium: most adults don't reach optimal levels through diet alone — see supplement table above.
- When to supplement electrolytes: during or after long exercise, in hot weather, during periods of fasting or TRE.
What's not worth buying
Most proprietary 'blends' with undisclosed doses | Testosterone boosters | Detox teas | Most weight-loss supplements | Any supplement that can't tell you the dose of each ingredient.
Key Takeaway
Vitamin D3+K2, Magnesium Glycinate and Omega-3 fill the most common genuine gaps. Get foundations right first — supplements are not the starting point.
Connections
Sleep
Magnesium Glycinate, Apigenin, and L-Theanine support sleep onset without being sleeping pills.
Hormones
Zinc and Vitamin D are essential cofactors in testosterone synthesis — deficiency reduces production.
Longevity — Slowing Biological Ageing
NMN/NR reliably raises NAD+ in humans — a cellular repair molecule that declines sharply with age.