Everyone brushes, but “how long, how often and how much toothpaste” varies. The NHS says to brush twice a day for about 2 minutes, and one of those times should be last thing before bed. Adult toothpaste should contain at least 1,350ppm fluoride, and you should not rinse straight after brushing. This sets out the NHS page “How to keep your teeth clean”.
1. Twice a day, about 2 minutes. Once last thing at night, once at another time.
2. At least 1,350ppm fluoride. Children 3 and under without decay can use a children’s paste of at least 1,000ppm.
3. Spit, don’t rinse. Rinsing washes away the concentrated fluoride left by the toothpaste, the page says.
How often and how long — NHS
The NHS says to brush twice a day for about 2 minutes each time. One should be last thing before you go to bed, and the page singles out night-time brushing as important. The other is at any other time of day. It says it doesn’t matter whether you use an electric or manual toothbrush.
Fluoride in toothpaste — by age
| Who | Fluoride | How much paste |
|---|---|---|
| Adults | At least 1,350ppm | No amount given on the page |
| Children (any age) | Family toothpaste is fine — 1,350 to 1,500ppm | See the two rows below |
| 3 and under, no decay | Lower-strength children’s paste is fine — at least 1,000ppm | Under 3: just a smear |
| 3 to 6 | Family paste of 1,350 to 1,500ppm | A pea-sized blob |
Children need to be helped or supervised until they’re at least 7, the page says. The fluoride level is on the toothpaste box or tube (our gloss).
After brushing — spit, don’t rinse
The NHS says not to rinse your mouth straight after brushing, because it washes away the concentrated fluoride in the remaining toothpaste. Spit the toothpaste out instead.
Floss and interdental brushes — before brushing
| Item | What the NHS says | Worth noting (our gloss) |
|---|---|---|
| When | It’s best to floss before brushing | The only item with an order |
| Floss length | Take 30cm to 45cm, hold 3cm or 4cm taut between your hands | Wind it round your fingers |
| Interdental brush | Should fit snugly between the teeth | Gaps may need different sizes |
Mouthwash — not straight after brushing
The NHS says to use mouthwash at a different time from brushing, such as after lunch. Using it straight after brushing would be like rinsing away the toothpaste’s fluoride (our reading — the same reason as “don’t rinse”). After a fluoride mouthwash, don’t eat or drink for 30 minutes.
As a daily routine — our example
| When | What to do | Basis |
|---|---|---|
| Morning | Brush about 2 minutes → spit, don’t rinse | The “other occasion” |
| After lunch | Mouthwash here, if you use it → 30 minutes without food (fluoride type) | “A different time” |
| Last thing at night | Floss → brush about 2 minutes → spit, don’t rinse | Night brushing matters; floss first |
Laying the NHS sentences out over a day is our example. Putting flossing at night is not something the NHS specifies.
Checklist
- ☐ Twice a day, about 2 minutes — once last thing at night
- ☐ Toothpaste with at least 1,350ppm fluoride
- ☐ Spit after brushing, don’t rinse
- ☐ Floss before brushing, 30 to 45cm
- ☐ Mouthwash at another time; 30 minutes without food after a fluoride one
- ☐ Help or supervise children until 7
Questions that remain
How often should I change my toothbrush?
The NHS page read here gives no replacement interval, so we give no number.
What about sweet food?
The WHO sugar line (free sugars under 10% of daily energy) is in how much sugar a day.
With a mouth ulcer, the NHS says to use a soft-bristled toothbrush and avoid toothpaste with sodium lauryl sulphate (mouth ulcers).
With toothache, the NHS says to use a soft brush and avoid flossing around the sore tooth — see a dentist after 2 days (toothache).
If bad breath is the worry, the NHS adds cleaning your tongue and between your teeth daily, and not rinsing straight after brushing (bad breath).
Sources
- NHS — How to keep your teeth clean — original (page last reviewed 30 June 2025, next review due 30 June 2028; checked 12 October 2026). Twice a day for about 2 minutes, last thing at night, 1,350ppm, 1,000ppm, 1,350 to 1,500ppm, smear and pea-sized, age 7, don’t rinse, floss 30 to 45cm and 3 to 4cm, 30 minutes after mouthwash.
- Not read. Korean agencies’ brushing guidance; any source on toothbrush replacement intervals.
- Added by us. The “worth noting” column and the daily routine example.
Where to check further
- Toothpaste ingredients — fluoride in ppm.
- Your dentist — interdental brush sizes.
Written 12 October 2026. The content follows the NHS original; the glosses and example are ours.