How to Build an Evidence-Based Supplement Stack

Step 1: Fill the gaps in your diet first

Before buying anything, ask: what am I actually deficient in? Most people in the UK are deficient in the same three or four nutrients — and the supplements with the strongest evidence are often the dullest ones. Start there.

The UK baseline stack

If you live in the UK and do not eat a highly varied diet with regular oily fish, you are almost certainly under-consuming several key nutrients. The evidence-based starting point for most adults:

• Vitamin D3 (1000 IU / 25mcg) — take year-round or at minimum Oct–March

• Magnesium glycinate (200–400mg elemental) — particularly if you struggle with sleep or muscle cramps

• Omega-3 (500mg+ combined EPA+DHA) — if you eat oily fish fewer than twice per week

• Vitamin B12 (1000mcg) — essential for vegans; optional for omnivores unless blood test shows deficiency

Step 2: Add goal-specific supplements

Once deficiencies are addressed, targeted supplementation based on your specific goals makes sense. Examples:

• Strength training? Add creatine monohydrate (3–5g/day)

• High stress? Ashwagandha KSM-66 (600mg/day)

• Poor gut health? Strain-specific probiotic

• Cognitive support? Lion's mane (early evidence, worth trying if you're curious)

Step 3: Get a blood test

The most useful thing you can do before spending money on supplements is a targeted blood test. At minimum, consider testing: vitamin D (25-OH), ferritin (iron stores), B12, folate, and a full blood count. Many GP surgeries will test these if you describe symptoms. Private tests are also widely available.

What to avoid

• Expensive "proprietary blends" with undisclosed individual doses

• Any product with more than 8–10 ingredients in one capsule

• Supplements marketed with before/after photos or celebrity endorsements

• Anything claiming to "detox", "cleanse" or "boost metabolism" without specific evidence

Budget guidance

A solid evidence-based stack covering vitamin D, magnesium, omega-3 and B12 (if vegan) costs approximately £25–40 per month from reputable UK suppliers. If you're spending significantly more than this, question whether the extra cost is justified by the evidence.

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