How to Stack Supplements: Putting Together a Sensible Stack – With Three Examples

Most supplement cupboards don't grow to a plan but through recommendations: a booster from a training partner, magnesium for cramps, zinc for winter, plus a multivitamin "just in case". In the end there are six tubs on the shelf, two of them contain the same thing – and nobody knows any more which of them actually does anything.

That's exactly why we built the Supplement Stack Builder. It answers three questions everyone should ask before buying anything: What fits my goal? How much and when? And do the products go together? In this article we explain how a good stack is built, how the tool calculates and where its limits are.

What makes a good supplement stack

A stack is the combination of supplements you take regularly – with dose and timing. Three rules separate a sensible stack from an expensive shelf:

The three rules of a good stack

1. 01SmallTwo to five items are enough for almost every goal. Every extra item costs money and attention and raises the risk of overlaps.
2. 02Evidence-basedIngredients with strong evidence for your goal come first – creatine, protein, caffeine, vitamin D when low. Everything else is a trial, not a foundation.
3. 03CoordinatedAdd up the nutrients from all products, check interactions and spread minerals across different meals.

And a fourth that comes before all others: supplements add, they don't replace. Sleep, enough protein from food and a sensible training plan do more than any tub. That's why the Stack Builder shows the basics first for each goal.

How the Stack Builder works – step by step

The process takes about two minutes and needs no sign-up.

1. Choose goals. There are eleven goals to choose from, from muscle gain and strength to endurance and fat loss, sleep, immune system, joints and shift work. You pick up to three, and the order counts: the first goal counts fully, the second at 80 per cent, the third at 65 per cent.

2. Profile. Body weight, age, diet (with meat, vegetarian, vegan), whether you regularly eat oily fish, lactose, training days, training time, long sessions, coffee per day and an optional monthly budget. Each of these changes the result – more on that in a moment.

3. Health. Blood thinners, high blood pressure, kidney, liver or thyroid conditions, antidepressants and sleeping pills, allergies to fish, shellfish or milk protein, coeliac disease. These exclude ingredients or trigger notes. During pregnancy and breastfeeding the tool deliberately builds no stack.

4. Your stack. Items appear in three levels – Core, Worth adding and Optional – each with dose, timing, evidence level, a matching Syrax product, monthly cost and the authorised EU claim, where there is one.

What the tool calculates in the background

Goals and evidence

Every ingredient has a value from 0 to 3 for each goal – creatine for example 3 for muscle gain and strength but only 1 for endurance, because it mainly supports short, intense efforts. This value is weighted by the evidence:

Your profile changes recommendation and dose

• Season: from October to March the Central European sun barely suffices for vitamin D synthesis – vitamin D moves up. If you spend a lot of time outdoors in summer, it's suggested less often.
• Diet: without meat and fish creatine stores are usually lower, so creatine matters more. On a vegan diet iodine and a note on vitamin B12 are added, while whey and fish oil drop out.
• Fish: if you regularly eat oily fish, you need omega-3 capsules less often – the dose is halved.
• Body weight: the caffeine amount is based on about 3 mg per kilogram. Lighter people get half a booster serving; from 85 kg creatine rises to 5 g.
• Coffee: each cup counts as about 90 mg in the caffeine check. If you already drink plenty of coffee, you don't need a booster.
• Training time: booster, shake and electrolytes only appear on training days – and if you train in the evening, you get a note about sleep.
• Age: from 55 there's a specific authorised EU claim for creatine: daily creatine consumption can enhance the effect of resistance training on muscle strength (3 g daily, at least three resistance sessions per week).

The upper-limit check

This is the part missing from most supplement routines. The tool adds up the nutrients of all selected products – including shop products you add yourself and your coffee – and compares the total with two limits:

The EFSA upper level is the safety line: if it's exceeded, the tool shows a red warning – and automatically deselects the weaker item among its own suggestions. An example: electrolyte powder (242 mg magnesium) plus magnesium tablets (200 mg) would make 442 mg of magnesium from supplements. The Stack Builder keeps the product that matters more for your goal and explains why the other is missing.

The BfR values are cautious proposals for individual products that already factor in intake from food. If a stack is above them, a note appears instead of a warning – which, by the way, also applies to some of our own products, such as the vitamin D drops with 25 µg per drop. We show it anyway because you should know.

Interactions

Besides the totals, the tool checks known combinations that call for caution:

• Blood thinners: vitamin K can affect vitamin K antagonists – the tool then chooses vitamin D without K2 and advises checking with your doctor, likewise for omega-3.
• Kidney disease and blood pressure drugs: potassium from electrolytes and magnesium are excreted by the kidneys; with ACE inhibitors, ARBs or potassium-sparing diuretics there's a note.
• Thyroid: iodine and ashwagandha drop out with thyroid conditions.
• Antidepressants, sleeping pills and sedatives: no melatonin and no ashwagandha without medical advice.
• High blood pressure or caffeine sensitivity: no booster.
• Minerals: zinc, magnesium and calcium compete for absorption – the weekly plan puts them at different meals.

Three example stacks

How different the results are is shown by three typical profiles – as the Stack Builder suggests them in November.

What we deliberately don't recommend

What's missing from the stack matters as much as what's in it. For each goal the tool shows what's often advertised but has no proven extra benefit:

• BCAA: if you eat enough protein, you get them anyway. More in BCAA or EAA?
• Glutamine: no proven benefit for muscle gain or recovery in healthy athletes.
• Fat burners and green tea extract: no meaningful effect on body fat; high-dose green tea extract can stress the liver according to EFSA. The calorie deficit does the work – see Lose fat, keep muscle.
• Testosterone boosters: tribulus, maca and co. don't measurably raise testosterone in healthy men.

Save, share, print

• Weekly plan as PDF: seven days, all meals and training days, plus every item with dose, timing and notes. The PDF is created in your browser.
• Share: the link contains all settings – whoever opens it sees your stack and can keep editing it. Handy for training partners or your doctor.
• Save: "My stacks" are stored in your browser. You don't need an account.
• Your own products: you can add more Syrax products from the shop; they appear in the plan, and known products count towards the upper-limit check.

And because supplements are only ever as good as the training behind them: the Stack Builder stores goals and training days so that the workout plan generator picks them up – and vice versa. Plan and stack fit together automatically: in the workout plan you see for every day what your stack schedules. If you work shifts, the shift work sleep optimizer gives you a matching sleep plan.

The tool's limits

The Stack Builder is designed for healthy adults. It doesn't know your blood values, it replaces no diagnosis and no medical advice. If you take medication, have a chronic condition, are pregnant or breastfeeding, check every supplement with your doctor first. That's why the tool never recommends iron, only advising you to have ferritin and a blood count checked. How to interpret lab values as an athlete is covered in Blood values for athletes.

Conclusion

The most important question when buying supplements isn't "What's good?" but "What's good for me – and does it fit with what I already take?". The Supplement Stack Builder answers exactly that question in two minutes. Try it, print out your weekly plan – and if you find you don't need half of your shelf, the tool has already paid off.

Sources: Regulation (EU) No 432/2012 – authorised health claims · Implementing Regulation (EU) 2017/672 – creatine from 55 · Verbraucherzentrale: BfR maximum level proposals (opinion 006/2024, German) · Kreider et al.: ISSN Position Stand Creatine (2017) · Guest et al.: ISSN Position Stand Caffeine (2021) · Morton et al.: Protein supplementation – meta-analysis (2018)