Plan supplements · log intake · check interactions
Supplement planner with interaction check
With Stackwell you plan your supplements by time of day, tick off every intake and see which ingredients compete for absorption or work together, each with its source. Stackwell is a web app by Vitalli, free to use and without affiliate links. You can even check known interactions between supplements without an account in the combination check.
- Free to use
- German and English
- No ads, no affiliate links
- Installable as an app on your phone
Try it now, no account
Supplement Combination Check
Pick two or more ingredients and see known interactions, spacing rules and synergies with primary sources, plus EFSA upper levels. Your selection stays in your browser.
Plan your supplements
Your plan says what you take and when. You can create several plans and keep one active.
Six intake times
Morning, mid-morning, midday, afternoon, evening and before bed. Optionally with an exact time.
Amount and meals
For each product you set amount and unit and whether you take it with a meal, before, after, on an empty stomach or any time.
Ingredients, not brand names
Stackwell works with the ingredients of your products. You see how much of an ingredient adds up per day, even if it is in several products.
Reference values as information
Daily amounts per ingredient are shown next to reference values, including NIH and EFSA, and next to known upper levels. That is a comparison, not a dosage recommendation.
Log your intake
The daily plan on your start page doubles as your intake log.
Tick off or skip
Mark every planned intake as taken or skipped. Undo a mistake and correct the time afterwards.
Journal with calendar
For every day you see what you took, skipped or did not log, and how much of your plan you kept to.
Reminders
Turn on push notifications and Stackwell reminds you of your intake.
Stock and shopping list
Mark a product as running low and it goes on your shopping list.
Interactions between supplements
Stackwell keeps its own table of ingredient pairs that compete for absorption, work together or depend on each other. The interaction graph in the app and the public combination check use the same data. It currently holds 164 entries: 19 conflicts, 76 synergies and 69 dependencies.
We checked 13 pairs against primary sources, for example:
Compete for absorption
Calcium inhibits iron absorption from the same meal
Sources:
Caution
High zinc intake over time lowers copper status
Sources:
Work together
Vitamin C increases non-haem iron absorption
Sources:
Caution
St. John’s wort and 5-HTP: both act on serotonin
Sources:
In the app, a network graph shows the pairs for the ingredients in your active plan, so you can put pairs that compete into different intake times.
All checked pairs in the combination checkWhat about medicines?
Stackwell contains 42 rules on known interactions between groups of medicines and supplements. They apply when you add your medicines to your profile and let the AI assistant (part of Vitalli Plus) create a plan.
Depending on the rule, the plan leaves out products with the affected ingredient (15 rules), notes the time gap needed to the medicine (8) or shows a note (19).
Groups of medicines covered
- Anticoagulants (vitamin K antagonists such as phenprocoumon and warfarin, direct oral anticoagulants)
- Acetylsalicylic acid
- Thyroid hormone (levothyroxine)
- Metformin and other diabetes medicines
- Antidepressants (SSRIs, MAO inhibitors)
- Statins
- ACE inhibitors and ARBs
- Beta blockers
- Diuretics
- Immunosuppressants
- Antibiotics (fluoroquinolones, tetracyclines)
- Lithium
- Acid blockers (proton pump inhibitors)
- Anticonvulsants
- Corticosteroids
This is not a complete medicine check. Many substances, doses and combinations are not covered, and the public combination check does not check medicines. If you take medicines, discuss every supplement with your doctor or pharmacist first.
What Stackwell does not do
- Stackwell does not replace advice from your doctor or pharmacist and does not diagnose anything.
- Stackwell gives no individual dosage recommendation. Reference values and upper levels are information.
- Stackwell does not recommend products, does not sell supplements and uses no affiliate links.
- A missing note does not mean a combination is harmless.
- During pregnancy and breastfeeding, with chronic conditions and for children, discuss every supplement with a doctor.
What does it cost?
Plan, intake log, reminders, interaction graph and combination check are free. The AI assistant is part of Vitalli Plus, one subscription for all Vitalli apps, which cannot be ordered yet. Stackwell has no subscription of its own.
Frequently asked questions
Which app can I use to plan my supplements and track my intake?
With Stackwell you set intake time, amount and meal timing for each product and tick off every intake in your daily plan. A journal shows what you took on which day, and the app can remind you by push notification. Stackwell is free to use and part of Vitalli.
Is there a tool that checks interactions between supplements?
Yes. Stackwell's Supplement Combination Check is free and needs no account: pick two or more ingredients and see known conflicts, spacing rules and synergies. It shows 13 pairs with rationale and primary source, plus EFSA upper levels. Your selection stays in your browser.
Does Stackwell also check interactions between supplements and medicines?
Partly. Stackwell knows 42 rules for known interactions, for example between anticoagulants and vitamin K, thyroid hormone and calcium or iron, metformin and vitamin B12, or antidepressants and St. John's wort. They apply when you add your medicines to your profile and let the AI assistant (part of Vitalli Plus) create a plan. This is not a complete medicine check and does not replace talking to your doctor or pharmacist. The public combination check does not check medicines.
Where does the interaction information come from?
From Stackwell's own table of ingredient pairs. For 13 pairs we checked the statement against primary sources (EFSA, NIH, studies) and link them. Pairs without a listed source are shown in the combination check with their kind only, without a rationale.
Does Stackwell tell me how much to take?
No. Stackwell shows how much of an ingredient adds up in your plan and puts it next to reference values and known upper levels. An individual dosage belongs with your doctor.
What does Stackwell cost?
Planning, intake logging, reminders and the interaction check are free. The AI assistant is part of Vitalli Plus, one subscription for all Vitalli apps, which cannot be ordered yet. Stackwell does not sell supplements and shows no ads.
Do I need an app from the app store?
No. Stackwell runs in the browser and can be added to your phone's home screen like an app. You sign in with your Vitalli account, which also works for the other Vitalli apps.
Set up your plan
Sign up for free with a Vitalli account, add your products and tick off your first intake.
Open beta: sign up without an invitation.