Microbiome Diet Habit Score
Gut bacteria can only be studied with stool tests, and there's no agreed "microbiome age" for individuals. This page does not estimate one. It counts diet habits discussed in microbiome research, such as fibre and plant variety. For digestion and activity habits, see the Gut Health Habit Score.
Before you start
Method : Microbiome Diet Habit Score — a custom points score written by this site. Each answer adds or subtracts the points shown in the Methodology table below.
Validation : Unvalidated. The points have never been tested against any laboratory measurement or health outcome, and the result is not an age.
Review : not reviewed by a qualified clinician. Educational only — not a diagnosis or a medical test.
Blood in your poo, a lasting change in bowel habits, or unexplained weight loss should be checked by a doctor (NHS).
Your answers stay in this browser tab; nothing is sent or stored.
NHS: 30 g a day.
Answer the questions, then press Calculate score.
How to Use This Calculator
- Answer each question.
- Press Calculate score.
- Read the breakdown and suggestions.
Methodology & assumptions
Your score is the sum of the points below. The weights are our own judgement. The old version added made-up years for probiotics, antibiotics, bloating and bowel regularity and gave a "microbiome age". Symptoms moved to the doctor note; medicines and supplements were removed with the age output.
| Factor | Answer | Points |
|---|---|---|
| Fibre (vegetables, fruit, wholegrains, beans, nuts) | With most meals | 0 |
| Some days | +1 | |
| Rarely | +2 | |
| Different plant foods in a typical week | 20 or more | 0 |
| 10–19 | 0 | |
| Under 10 | +1 | |
| Ultra-processed food and drinks | Rarely | 0 |
| Some days | +1 | |
| Most meals | +2 | |
| Fermented foods (yoghurt, kefir, sauerkraut, kimchi) | Most weeks | 0 |
| Sometimes | 0 | |
| Never | +1 |
Worked examples
Rarely eats fibre, under 10 plant foods, ultra-processed at most meals, never fermented foods: 2 + 1 + 2 + 1 = +6 points.
Fibre most meals, 20+ plants, rarely ultra-processed, fermented foods most weeks: 0 points.
Understanding your result
This counts diet habits you reported. It is not a microbiome test and not an age. Health-agency guidance linked below is general and based on populations, not on this score.
Sources & further reading
The points table is our own convention and is not taken from these sources.
Frequently Asked Questions
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